Matoba Sumito

Institute of Low Temperature Science Pan-Okhotsk Research CenterAssistant Professor
Arctic Research CenterAssistant Professor
Last Updated :2025/02/13

■Researcher basic information

Degree

  • Ph. D (Science), Graduate University for Advanced Studies

Profile Information

  • 季節海氷域のおける水・物質循環プロセスの解明に取り組んでいます。具体的には


    • 極夜明けに海氷表面から放出されるエアロゾルとその大気中での化学反応

    • ノースウォーターポリニアが冬季の降雪プロセスにに与える影響

    • グリーンランド氷床沿岸部の雪氷試料・アイスコアを用いた近年の大気/海洋環境の復元

    などです。


     グリーンランド最北の村のシオラパルクにおいて、冬〜春季に海氷、降雪、エアロゾル、気象観測を実施しています。また、北海道の紋別市でも観測を開始しました。


     これらの研究は、SE-Domeアイスコアプロジェクト(科研S_18H05292)、ArCSII(北極域研究加速プロジェクト)、北海道大学低温科学研究所附属環オホーツク観測センター事業費などのプロジェクトにて実施されています。


     


    それ以外にも


    • モンゴル・ポターニン氷河の表面融解に不十分物が及ぼす影響

    • 季節積雪の融解における表面融解と不純物濃縮の定量的プロセス評価

    • bonchi powderプロジェクト

    の研究を実施しています。

Researchmap personal page

Researcher number

  • 30391163

Research Keyword

  • Kamchatka
  • Alaska
  • Greenland
  • 古気候
  • 氷河
  • アイスコア

Research Field

  • Natural sciences, Atmospheric and hydrospheric science

Educational Organization

■Career

Career

  • Apr. 2007 - Present
    Hokkaido University, Institute of Low Temperature Science, 助教
  • Mar. 2005 - Mar. 2007
    Hokkaido University, Institute of Low Temperature Science, 助手
  • Jan. 2003 - Feb. 2005
    国立環境研究所, 基盤研究ラボ, 重点研究支援協力員
  • Apr. 2001 - Dec. 2002
    National Institute of Polar Research, 研究機関研究員
  • Oct. 1998 - Mar. 2001
    Hokkaido University, Institute of Low Temperature Science, 中核的研究機関研究員

Educational Background

  • Apr. 1995 - Mar. 1998, The Graduate University for Advanced Studies, 数物科学研究科, 極域科学専攻
  • Apr. 1993 - Mar. 1995, 京都大学大学院, 理学研究科, 化学専攻
  • Apr. 1989 - Mar. 1993, Kyoto University, Faculty of Science

Committee Memberships

  • Apr. 2020 - May 2024
    (公社)日本雪氷学会北海道支部, 理事(副支部長), Society
  • May 2013 - May 2017
    (公社)日本雪氷学会, 理事, Society
  • Apr. 2013 - Apr. 2016
    (公社)日本雪氷学会, 北海道支部理事, Society
  • 2011 - 2013
    (公社)日本雪氷学会, Bulletin of Glaciological Research 編集委員, Society
  • 2009 - 2013
    (公社)日本雪氷学会, 雪氷編集委員, Society
  • 2008
    日本雪氷学会, 広報委員, Society
  • 2005 - 2006
    日本雪氷学会, 北海道支部会計担当幹事, Society

■Research activity information

Awards

  • Sep. 2019, (公社)日本雪氷学会, 論文賞               
    バフィン湾周辺の環境がグリーンランド北西部の 降雪中の d-excess と化学成分に与える影響
    黒﨑 豊・的場 澄人・飯塚 芳徳・庭野 匡思・谷川 朋範・青木 輝夫
  • 2008, 寒地技術賞(地域振興部門)               
    Japan

Papers

  • Contrasting Responses of Ion Concentration Variations to Atmospheric Patterns in Central Himalayan Ice Cores
    Akane Tsushima, Nao Esashi, Sumito Matoba, Yoshinori Iizuka, Ryu Uemura, Kouji Adachi, Takeshi Kinase, Motohiro Hirabayashi, Kaoru Kawakami, Rijan B. Kayastha, Koji Fujita
    Journal of Geophysical Research: Atmospheres, 130, 2, American Geophysical Union (AGU), 23 Jan. 2025
    Scientific journal, Abstract

    We analyzed the water‐soluble chemical composition of an 81.2‐m‐long ice core collected in 2019 from 6,000 m elevation on a south‐facing glacier in the Nepal Himalaya. The ice core chronology is based on variability in nitrate and calcium ions, which reveal an apparently seasonal periodicity (with winter maxima) throughout the core's length. Two annual boundaries are consistent with the tritium peak representing nuclear tests conducted in 1963 CE and with the spike in sulfate ions due to the eruption of Krakatau in 1883 CE. The ice core spans 145 years from 1875 to 2019 CE. Dating uncertainties due to the layer counting methodology were estimated as year for 1963–2019 CE and years for 1875–1963 CE. Comparison with earlier ice cores drilled on the northern side of the Himalayas revealed that the ion components exhibit inverse correlations with two key climatic indices: the North Atlantic Oscillation and Southern Oscillation Index. Composite analysis of reanalysis climate data suggests that these inverse relationships reflect springtime pressure patterns, which show regional differences between the northern and southern sides of the Himalayan range.
  • Technical note: High-resolution analyses of concentrations and sizes of refractory black carbon particles deposited in northwestern Greenland over the past 350 years – Part 1: Continuous flow analysis of the SIGMA-D ice core using the wide-range Single-Particle Soot Photometer and a high-efficiency nebulizer
    Kumiko Goto-Azuma, Remi Dallmayr, Yoshimi Ogawa-Tsukagawa, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Motohiro Hirabayashi, Jun Ogata, Kyotaro Kitamura, Kenji Kawamura, Koji Fujita, Sumito Matoba, Naoko Nagatsuka, Akane Tsushima, Kaori Fukuda, Teruo Aoki
    Atmospheric Chemistry and Physics, 24, 22, 12985, 13000, Copernicus GmbH, 25 Nov. 2024
    Scientific journal, Abstract. Ice cores can provide long-term records of refractory black carbon (rBC), an important aerosol species closely linked to the climate and environment. However, previous studies of ice cores only analyzed rBC particles with a diameter of < 500 nm, which could have led to an underestimation of rBC mass concentrations. Information on the size distribution of rBC particles is very limited, and there are no Arctic ice core records of the temporal variation in rBC size distribution. In this study, we applied a recently developed improved technique to analyze the rBC concentration in an ice core drilled at the SIGMA-D site in northwestern Greenland. The improved technique, which uses the modified Single-Particle Soot Photometer (SP2) and a high-efficiency nebulizer, widens the measurable range of rBC particle size. For high-resolution continuous analyses of ice cores, we developed a continuous flow analysis (CFA) system. Coupling of the improved rBC measurement technique with the CFA system allows accurate high-resolution measurements of the size distribution and concentration of rBC particles with a diameter between 70 nm and 4 µm, with minimal particle losses. Using this technique, we reconstructed the size distributions and the number and mass concentrations of rBC particles during the past 350 years. On the basis of the size distributions, we assessed the underestimation of rBC mass concentrations measured using the conventional SP2s. For the period 2003–2013, the underestimation of the average mass concentration would have been 12 %–31 % for the SIGMA-D core.
  • High-resolution analyses of concentrations and sizes of black carbon particles deposited on northwest Greenland over the past 350 years – Part 2: Seasonal and temporal trends in black carbon originated from fossil fuel combustion and biomass burning
    Kumiko Goto-Azuma, Yoshimi Ogawa-Tsukagawa, Kaori Fukuda, Koji Fujita, Motohiro Hirabayashi, Remi Dallmayr, Jun Ogata, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Sumito Matoba, Teruo Aoki
    Copernicus GmbH, 23 May 2024
    Abstract. The roles and impacts of black carbon (BC), an important aerosol species affecting Earth’s radiation budget, are not well understood owing to lack of accurate long-term observations. To study the temporal changes in BC since the pre-industrial period, we analysed BC in an ice core drilled in northwest Greenland. Using an improved technique for BC measurement and a continuous flow analysis system, we obtained accurate and high temporal resolution records of BC particle size and mass/number concentrations for the past 350 years. Number and mass concentrations, which both started to increase in the 1870s associated with inflow of anthropogenically derived BC, reached their maxima in the 1910s–1920s and then subsequently decreased. On the basis of backward trajectory analyses, we found that North America was the dominant source region of the anthropogenic BC in the ice core. The increase in anthropogenic BC shifted the annual concentration peaks of BC from summer to winter–early spring. After BC concentrations diminished to pre-industrial levels, the annual peak concentration of BC returned to the summer. We found that anthropogenic BC particles were larger than biomass burning BC particles. By separating the BC in winter and summer, we reconstructed the temporal variations in BC that originated from biomass burning, including the period with large anthropogenic input. The BC that originated from biomass burning showed no trend of increase until the early 2000s. Finally, possible albedo reductions due to BC are discussed. Our new data provide key information for validating aerosol and climate models, thereby supporting improved projections of future climate and environment.
  • Technical note: High-resolution analyses of concentrations and sizes of black carbon particles deposited on northwest Greenland over the past 350 years – Part 1. Continuous flow analysis of the SIGMA-D ice core using a Wide-Range Single-Particle Soot Photometer and a high-efficiency nebulizer
    Kumiko Goto-Azuma, Remi Dallmayr, Yoshimi Ogawa-Tsukagawa, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Motohiro Hirabayashi, Jun Ogata, Kyotaro Kitamura, Kenji Kawamura, Koji Fujita, Sumito Matoba, Naoko Nagatsuka, Akane Tsushima, Kaori Fukuda, Teruo Aoki
    Copernicus GmbH, 23 May 2024
    Abstract. Ice cores can provide long-term records of black carbon (BC), an important aerosol species closely linked to the climate and environment. However, previous studies of ice cores only analysed BC particles with diameter of <600–850 nm, which could have led to underestimation of BC mass concentrations. Information on the size distribution of BC particles is very limited, and there are no Arctic ice core records of the temporal variation in BC size distribution. In this study, we applied a recently developed improved technique to analyse the BC concentration in an ice core drilled at the SIGMA-D site in northwest Greenland. The improved technique, which uses a modified Single-Particle Soot Photometer and a high-efficiency nebulizer, widens the measurable range of BC particle size. For high-resolution continuous analyses of ice cores, we developed a continuous flow analysis (CFA) system (resolution: 10–40 mm). Coupling of the improved BC measurement technique with the CFA system allows accurate high-resolution measurements of the size distribution and concentration of BC particles with diameter between 70 nm and 4 μm, with minimal particle losses. Using this technique, we reconstructed the size distributions and the number and mass concentrations of BC particles during the past 350 years. On the basis of the size distributions, we assessed the underestimation of BC mass concentrations measured using the conventional method. For the period 2003–2013, the underestimation of the average mass concentration would have been 12 %–17 % for the SIGMA-D core.
  • Field activities at the SIGMA-A site, northwestern Greenland ice sheet, 2023
    Masashi NIWANO, Motoshi NISHIMURA, Rigen SHIMADA, Tetsuhide YAMASAKI, Nozomu OHKAWARA, Sojiro SUNAKO, Teruo AOKI, Akihiro HASHIMOTO, Tomonori TANIKAWA, Sumito MATOBA, Satoru YAMAGUCHI
    Bulletin of Glaciological Research, 42, 61, 68, Japanese Society of Snow and Ice, 2024
    Scientific journal
  • Development of a handheld integrating sphere snow grain sizer (HISSGraS)
    Teruo Aoki, Akihiro Hachikubo, Motoshi Nishimura, Masahiro Hori, Masashi Niwano, Tomonori Tanikawa, Konosuke Sugiura, Ryo Inoue, Satoru Yamaguchi, Sumito Matoba, Rigen Shimada, Hiroshi Ishimoto, Jean-Charles Gallet
    Annals of Glaciology, 1, 12, Cambridge University Press (CUP), 29 Nov. 2023
    Scientific journal, Abstract

    We developed a Handheld Integrating Sphere Snow Grain Sizer (HISSGraS) for field use to measure the specific surface area (SSA) of snow. In addition to snow samples, HISSGraS can directly measure snow surfaces and snow pit walls. The basic measurement principle is the same as that of the IceCube SSA instrument. The retrieval algorithm for SSA from reflectance employs two conversion equations formulated using spherical and nonspherical grain shape models. We observed SSAs using HISSGraS, IceCube and the gas adsorption method in a snowfield in Hokkaido, Japan. Intercomparison of the results confirmed that with HISSGraS direct measurement, SSA profile observations can be completed in just ~1/10 the time required for measurement of snow samples. Our results also suggest that HISSGraS and IceCube have similar accuracy when the same snow samples are measured using the same grain shape model. However, SSAs of near-surface snow layers measured using the three techniques exhibited some biases, possibly due to rapid snow metamorphism or melting during measurement and some technical issues with optical techniques. When excluding SSA data for the surface layer, which metamorphosed remarkably during measurement, IceCube- and HISSGraS-derived SSAs correlated strongly with those obtained by gas adsorption and HISSGraS accuracy is 21–34%.
  • SE‐Dome II Ice Core Dating With Half‐Year Precision: Increasing Melting Events From 1799 to 2020 in Southeastern Greenland
    Kaoru Kawakami, Yoshinori Iizuka, Mahiro Sasage, Mai Matsumoto, Takeshi Saito, Akira Hori, Sakiko Ishino, Shuji Fujita, Koji Fujita, Keita Takasugi, Takumi Hatakeyama, Saaya Hamamoto, Akihisa Watari, Nao Esashi, Miu Otsuka, Ryu Uemura, Kazuho Horiuchi, Masahiro Minowa, Shohei Hattori, Teruo Aoki, Motohiro Hirabayashi, Kenji Kawamura, Sumito Matoba
    Journal of Geophysical Research: Atmospheres, 128, 20, American Geophysical Union (AGU), 13 Oct. 2023
    Scientific journal, Abstract

    Arctic warming has accelerated surface melting even in the highland areas of the Greenland ice sheet (GrIS). Understanding the relationship between climate and surface melting is essential for improving the estimates of ice‐sheet mass loss due to warming. Here we analyze a 250 m‐long ice core from the southeastern dome of GrIS (SE‐Dome site; 67°19′17″ N, 36°47′03″ W, 3,161 m a.s.l.), where the annual mean temperature is −20.9°C and the accumulation rate is high and there is a large discrepancy among climate models regarding snow accumulation estimates. A time scale was established for 1799–2020 with a half‐year uncertainty using annual counting of H2O2 concentration and five time horizons determined by electrical conductivity, melt events, and tritium concentration. The annual accumulation rate from the ice core shows no significant trend over 221 years and has an average of 1.04 ± 0.20 m w.e. year−1. In contrast, the frequency and thickness of refrozen melt layer (ML) have increased over 221 years, and are synchronized with temperature changes in the Arctic. The thickness of MLs correlates positively with the time‐integrated summer temperature anomaly using a reanalysis of air temperature. The in‐situ accumulation records in the southeastern GrIS provide an important basis for correcting reanalysis data such as ERA5, which in turn are valuable for improving regional climate models.
  • Quality-controlled meteorological datasets from SIGMA automatic weather stations in northwest Greenland, 2012–2020
    Motoshi Nishimura, Teruo Aoki, Masashi Niwano, Sumito Matoba, Tomonori Tanikawa, Tetsuhide Yamasaki, Satoru Yamaguchi, Koji Fujita
    Earth Science System Data, 28 Apr. 2023, [Peer-reviewed], [International Magazine]
  • Increased oceanic dimethyl sulfide emissions in areas of sea ice retreat inferred from a Greenland ice core
    Yutaka Kurosaki, Sumito Matoba, Yoshinori Iizuka, Koji Fujita, Rigen Shimada
    Communications Earth & Environment, 3, 1, Springer Science and Business Media LLC, 26 Dec. 2022
    Scientific journal, Abstract

    Ocean phytoplankton are an important source of dimethyl sulfide, which influences marine cloud formation. Model studies suggest that declines in Arctic sea ice may lead to increased dimethyl sulfide emissions, however observational support is lacking. Here, we present a 55-year high-resolution ice core record of methane sulfonic acid flux, an oxidation product of dimethyl sulfide, from the southeast Greenland Ice Sheet. We infer temporal variations in ocean dimethyl sulfide emissions and find that springtime (April–June) fluxes of methane sulfonic acid correlate well with satellite-derived chlorophyll-a concentration in the Irminger Sea. Summertime (July–September) methane sulfonic acid fluxes were 3 to 6 times higher between 2002–2014 than 1972–2001. We attribute this to sea ice retreat day becoming earlier and a coincident increase in chlorophyll-a concentration in the adjacent open coastal waters.
  • Inclusions in ice layers formed by melting and refreezing processes in a Greenland ice core
    Kaoru Kawakami, Yoshinori Iizuka, Sumito Matoba, Teruo Aoki, Takuto Ando
    Journal of Glaciology, 1, 13, Cambridge University Press (CUP), 21 Nov. 2022
    Scientific journal, Abstract

    In recent decades, surface melting on the inland Greenland ice sheet has increased, leading to significant meltwater-refreezing in the snow and firn. Increased knowledge of the physical and chemical characteristics of these melt features (i.e., ice layers) is needed to help estimate future global sea-level rise. Here, using a combination of microscopy and spectroscopy, we investigate the size, shape, location, and chemical compositions of inclusions in 12 ice layers of the SIGMA-A ice core in the northwestern Greenland ice sheet (78°03′06″N, 67°37′42″W, 1490 m a.s.l.). In the ice layers, we found inclusions exceeding 30 μm diameter that could only be formed by melting–refreezing, which we classify into columnar-, particle-, and rod-like inclusions. We propose that the smaller columnar- and particle-like inclusions of solid Na2SO4⋅10H2O and CaSO4⋅2H2O form first, within the ice grains, followed by the larger rod-like inclusions of brines with mainly Na+ and Cl in grain boundaries. Our results suggest a new proxy that may help identify past warm climates in deeper ice cores in Greenland and for studying future ice sheet melting behavior.
  • High Flux of Small Sulfate Aerosols During the 1970s Reconstructed From the SE‐Dome Ice Core in Greenland
    Y. Iizuka, R. Uemura, H. Matsui, N. Oshima, K. Kawakami, S. Hattori, H. Ohno, S. Matoba
    Journal of Geophysical Research: Atmospheres, 16 Sep. 2022, [Peer-reviewed]
    English, Scientific journal
  • Gypsum formation from calcite in the atmosphere recorded in aerosol particles transported and trapped in Greenland ice core sample is a signature of secular change of SO2 emission in East Asia
    Chihiro Miyamoto, Yoshinori Iizuka, Sumito Matoba, Shohei Hattori, Yoshio Takahashi
    Atmospheric Environment, 278, 119061, 119061, Elsevier BV, Jun. 2022, [Peer-reviewed]
    Scientific journal
  • Developing an insulation box with automatic temperature control for PM2.5 measurements in cold regions
    Teppei J. Yasunari, Shigeto Wakabayashi, Yutaka Matsumi, Sumito Matoba
    Journal of Environmental Management, 311, 114784, 114784, Elsevier BV, Jun. 2022
    Scientific journal
  • Estimation of Seasonal Snow Mass Balance all over Japan Using a High-Resolution Atmosphere-Snow Model Chain
    Masashi Niwano, Masami Suya, Koichi Nagaya, Satoru Yamaguchi, Sumito Matoba, Ikuo Harada, Nozomu Ohkawara
    SOLA, 18, 193, 198, Meteorological Society of Japan, 2022
    Scientific journal
  • Ground-based measurements for the validation of snow/ice products in optical remote sensing
    Tomonori Tanikawa, Teruo Aoki, Masahiro Hori, Akihiro Hachikubo, Masashi Niwano, Konosuke Sugiura, Sumito Matoba, Rigen Shimada
    Journal of the Remote Sensing Society of Japan, 41, 5, 582, 594, Dec. 2021
    Japanese, Scientific journal
  • Spectral degree of linear polarization and neutral points of polarization in snow and ice surfaces
    Tomonori Tanikawa, Kazuhiko Masuda, Hiroshi Ishimoto, Teruo Aoki, Masahiro Hori, Masashi Niwano, Akihiro Hachikubo, Sumito Matoba, Konosuke Sugiura, Takenobu Toyota, Nozomu Ohkawara, Knut Stamnes
    Journal of Quantitative Spectroscopy and Radiative Transfer, 273, 107845, 107845, Elsevier BV, Oct. 2021, [Peer-reviewed]
    English, Scientific journal
  • Quantifying Relative Contributions of Light‐Absorbing Particles from Domestic and Foreign Sources on Snow Melt at Sapporo, Japan during the 2011–2012 Winter
    M. Niwano, M. Kajino, T. Kajikawa, T. Aoki, Y. Kodama, T. Tanikawa, S. Matoba
    Geophysical Research Letters, American Geophysical Union (AGU), 09 Aug. 2021
    Scientific journal
  • Ice Core Drilling and the Related Observations at SE-Dome site, southeastern Greenland Ice Sheet
    Yoshinori IIZUKA, Sumito MATOBA, Masahiro MINOWA, Tetsuhide YAMASAKI, Kaoru KAWAKAMI, Ayako KAKUGO, Morihiro MIYAHARA, Akihiro HASHIMOTO, Masashi NIWANO, Tomonori TANIKAWA, Koji FUJITA, Teruo AOKI
    Bulletin of Glaciological Research, 39, 1, 12, Japanese Society of Snow and Ice, Aug. 2021, [Peer-reviewed]
    English, Scientific journal, 30109798
  • Physically Based Summer Temperature Reconstruction From Melt Layers in Ice Cores
    Koji Fujita, Sumito Matoba, Yoshinori Iizuka, Nozomu Takeuchi, Akane Tsushima, Yutaka Kurosaki, Teruo Aoki
    Earth and Space Science, 8, 7, American Geophysical Union (AGU), Jul. 2021, [Peer-reviewed]
    Scientific journal, Previous reconstructions of summer temperatures from ice cores have relied on a statistical relationship between a melt layer and temperature observed at nearby stations. This study presents a novel method for reconstructing summer temperatures from melt layers in ice cores using an energy balance model that incorporates heat conduction and meltwater refreezing in the firn. We use the seasonal patterns in the ERA-Interim reanalysis data set for an ice core site to calculate the amounts of refreezing water within the firn under various summer mean temperature (SMT) and annual precipitation conditions, and prepared calibration tables containing these three variables. We then estimate the SMTs from the refreezing amount and annual accumulation, both of which can be obtained from an ice core. We apply this method to four ice cores that were recovered from sites with different climates: two sites on the Greenland Ice Sheet, one in Alaska, and one in Russian Altai. The reconstructed SMTs show comparable variations with those of observed temperatures at nearby stations. The nonlinear relationship between SMT and melt layer thickness differs between sites, indicating that a single linear approximation cannot be employed to estimate SMT. Sensitivity analyses suggest that the annual temperature range, amount of annual precipitation, and firn albedo (which is a time-invariant value in the model) significantly affect the relationship between SMT and melt layer thickness. This new method provides an alternative to existing approaches and yields an independent estimate of SMT from ice cores that have been affected by melting., 12352088
  • Variations in mineralogy of dust in an ice core obtained from northwestern Greenland over the past 100 years
    Naoko Nagatsuka, Kumiko Goto-Azuma, Akane Tsushima, Koji Fujita, Sumito Matoba, Yukihiko Onuma, Remi Dallmayr, Moe Kadota, Motohiro Hirabayashi, Jun Ogata, Yoshimi Ogawa-Tsukagawa, Kyotaro Kitamura, Masahiro Minowa, Yuki Komuro, Hideaki Motoyama, Teruo Aoki
    Climate of the Past, 17, 3, 1341, 1362, Copernicus GmbH, 21 Jun. 2021, [Peer-reviewed]
    English, Scientific journal, Abstract. Our study is the first to demonstrate a
    high-temporal-resolution record of mineral composition in a Greenland ice
    core over the past 100 years. To reconstruct past variations in the sources
    and transportation processes of mineral dust in northwestern Greenland, we
    analysed the morphology and mineralogical composition of dust in the SIGMA-D
    ice core from 1915 to 2013 using scanning electron microscopy (SEM) and
    energy-dispersive X-ray spectroscopy (EDS). The results revealed that the
    ice core dust consisted mainly of silicate minerals and that the composition
    varied substantially on multi-decadal and inter-decadal scales, suggesting
    that the ice core minerals originated from different geological sources in
    different periods during the past 100 years. The multi-decadal variation
    trend differed among mineral types. Kaolinite, which generally formed in
    warm and humid climatic zones, was abundant in colder periods (1950–2004),
    whereas mica, chlorite, feldspars, mafic minerals, and quartz, which
    formed in arid, high-latitude, and local areas, were abundant in warmer
    periods (1915–1949 and 2005–2013). Comparison to Greenland surface
    temperature records indicates that multi-decadal variation in the relative
    abundance of these minerals was likely affected by local temperature changes
    in Greenland. Trajectory analysis shows that the minerals were transported
    mainly from the western coast of Greenland in the two warming periods, which
    was likely due to an increase in dust sourced from local ice-free areas as a
    result of shorter snow/ice cover duration in the Greenland coastal region
    during the melt season caused by recent warming. Meanwhile, ancient deposits
    in northern Canada, which were formed in past warmer climates, seem to be the
    best candidate during the colder period (1950–2004). Our results suggest
    that SEM–EDS analysis can detect variations in ice core dust sources during
    recent periods of low dust concentration., 12352095
  • Isotopic evidence for acidity-driven enhancement of sulfate formation after SO2 emission control
    Shohei Hattori, Yoshinori Iizuka, Becky Alexander, Sakiko Ishino, Koji Fujita, Shuting Zhai, Tomás Sherwen, Naga Oshima, Ryu Uemura, Akinori Yamada, Nozomi Suzuki, Sumito Matoba, Asuka Tsuruta, Joel Savarino, Naohiro Yoshida
    Science Advances, 7, 19, eabd4610, eabd4610, American Association for the Advancement of Science (AAAS), May 2021, [Peer-reviewed]
    English, Scientific journal, After the 1980s, atmospheric sulfate reduction is slower than the dramatic reductions in sulfur dioxide (SO2) emissions. However, a lack of observational evidence has hindered the identification of causal feedback mechanisms. Here, we report an increase in the oxygen isotopic composition of sulfate (Δ17OSO42) in a Greenland ice core, implying an enhanced role of acidity-dependent in-cloud oxidation by ozone (up to 17 to 27%) in sulfate production since the 1960s. A global chemical transport model reproduces the magnitude of the increase in observed Δ17OSO42 with a 10 to 15% enhancement in the conversion efficiency from SO2 to sulfate in Eastern North America and Western Europe. With an expected continued decrease in atmospheric acidity, this feedback will continue in the future and partially hinder air quality improvements., 30109798
  • StudiesonAtmosphere,Snow/Ice,andGlacialMicrobesonGreenlandIceSheetbySIGMAandrelevant projects─Alinkage to theArCS IIProject─
    青木輝夫, 的場澄人, 庭野匡思, 朽木勝幸, 谷川朋範, 竹内 望, 山口 悟, 本山秀明, 藤田耕史, 山崎哲秀, 飯塚芳徳, 堀 雅裕, 島田利元, 植竹 淳, 永塚尚子, 大沼友貴彦, 橋本明弘, 石元裕史, 田中泰宙, 大島 長, 梶野瑞王, 足立光司, 黒﨑 豊, 杉山 慎, 津滝 俊, 東久美子, 八久保晶弘, 川上 薫, 木名瀨健
    Seppyo, 83, 2, 169, 191, 日本雪氷学会, Mar. 2021, [Peer-reviewed]
    Japanese, Scientific journal, 12352095
  • SurfaceenergybalanceobservedattheSIGMA-AsiteonthenorthwestGreenlandiceshee
    Hirose, S, Aoki, T, Niwano, M, Matoba, S, Tanikawa, T, Yamaguch, T, Yamasaki, T
    Seppyo, 82, 2, 143, 154, Mar. 2021, [Peer-reviewed]
    Japanese, Scientific journal, 30109798
  • Rapidly changing glaciers, ocean and coastal environments, and their impact on human society in the Qaanaaq region, northwestern Greenland
    Shin Sugiyama, Naoya Kanna, Daiki Sakakibara, Takuto Ando, Izumi Asaji, Ken Kondo, Yefan Wang, Yoshiki Fujishi, Shungo Fukumoto, Evgeniy Podolskiy, Yasushi Fukamachi, Minori Takahashi, Sumito Matoba, Yoshinori Iizuka, Ralf Greve, Masato Furuya, Kazutaka Tateyama, Tatsuya Watanabe, Shintaro Yamasaki, Atsushi Yamaguchi, Bungo Nishizawa, Kohei Matsuno, Daiki Nomura, Yuta Sakuragi, Yoshimasa Matsumura, Yoshihiko Ohashi, Teruo Aoki, Masashi Niwano, Naotaka Hayashi, Masahiro Minowa, Guillaume Jouvet, Eef van Dongen, Andreas Bauder, Martin Funk, Anders Anker Bjørk, Toku Oshima
    Polar Science, 27, 100632, 100632, Elsevier BV, Mar. 2021, [Peer-reviewed]
    Scientific journal, Environments along the coast of Greenland are rapidly changing under the influence of a warming climate in the Arctic. To better understand the changes in the coastal environments, we performed researches in the Qaanaaq region in northwestern Greenland as a part of the ArCS (Arctic Challenge for Sustainability) Project. Mass loss of ice caps and marine-terminating outlet glaciers were quantified by field and satellite observations. Measurements and sampling in fjords revealed the important role of glacial meltwater discharge in marine ecosystems. Flooding of a glacial stream in Qaanaaq and landslides in a nearby settlement were investigated to identify the drivers of the incidents. Our study observed rapid changes in the coastal environments, and their critical impact on the society in Qaanaaq. We organized workshops with the residents to absorb local and indigenous knowledge, as well as to share the results and data obtained in the project. Continuous effort towards obtaining long-term observations requiring involvement of local communities is crucial to contribute to a sustainable future in Greenland., 12352095
  • Increasing dust emission from ice free terrain in southeastern Greenland since 2000
    Tomomi Amino, Yoshinori Iizuka, Sumito Matoba, Rigen Shimada, Naga Oshima, Toshitaka Suzuki, Takuto Ando, Teruo Aoki, Koji Fujita
    Polar Science, 27, 100599, 100599, Elsevier BV, Mar. 2021, [Peer-reviewed]
    English, Scientific journal, Mineral dust plays a key role in both local and global climates. At high latitudes, atmospheric dust can affect ice-nuclei formation, and surface dust can reduce the albedo as well as increase subsequent ice melting. As a proxy for past climate, mineral dust is preserved in ice cores, but few studies have examined deposited dust in ice cores during the Anthropocene, especially after 2000. We measured dust concentrations in an ice core at the southeastern dome in Greenland (SE-Dome), and reconstructed the annual and seasonal dust fluxes during 1960–2014. We find the annual average flux during 1960–2014 to be 34.8 ± 13.5 mg m yr , a value about twice that of ice cores further inland. The more recent part of that period, 2000–2014, has the higher annual flux of 46.6 ± 16.2 mg m yr . The annual and autumn dust fluxes highly correlate with air temperature in Tasiilaq (r = 0.61 and 0.50, respectively), a coastal location in southeastern Greenland. Our results suggest that the local dust emissions at the coastal region are increasing due to a decreasing seasonal snow-cover area arising from coastal Greenland warming after 2000. −2 −1 −2 −1, 12352088
  • New insights into snow-atmosphere interaction through light-absorbing particles
    Niwano Masashi, Kajino Mizuo, Kajikawa Tomoki, AOKI Teruo, Kodama Yuji, Tanikawa Tomonori, Matoba Sumito
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2021, 83, 83, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2021
    Japanese
  • Inclusions in ice layers of an ice core, Greenland
    Kawakami Kaoru, Iizuka Yoshinori, Matoba Sumito, Aoki Teruo, Sugiyama Shin, Ando Takuto
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2021, 34, 34, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2021
    Japanese
  • The analysis of water stable isotopes of the ice core from Trambau glacier, Nepal Himalaya
    Esashi Nao, Tsushima Akane, Uemura Ryu, Iizuka Yoshinori, Matoba Sumito, Fujita Koji
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2021, 21, 21, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2021
    Japanese
  • Isotopic evidence for changes in sulfate formation after SO2 emission control
    Hattori Shohei, Iizuka Yoshinori, Alexander Becky, Ishino Sakiko, Fujita Koji, Zhai Shuting, Sherwen Tomas, Oshima Naga, Uemura Ryu, Yamada Akinori, Suzuki Nozomi, Matoba Sumito, Tsuruta Asuka, Savarino Joel, Yoshida Naohiro
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 68, 158, GEOCHEMICAL SOCIETY OF JAPAN, 2021
    Japanese, 大気中の硫酸の三酸素同位体組成は、大気中におけるSO2から硫酸への酸化過程における酸化剤の寄与率を反映して変動する。本研究では、グリーンランド南東ドームで採取された過去60年分のアイスコアを用い、その硫酸の三酸素同位体組成を分析することで、過去の大気化学反応の変化を復元した。硫酸の三酸素同位体組成は過去60年間で上昇し、SO2の液相O3酸化の寄与率が高くなっていたことを示した。硫酸の三酸素同位体組成の中和率やH+フラックスの変化とよく相関していた。SO2の液相O3酸化は酸性度が低いほど促進されることから、1980年代以降のSO2排出量の削減とアンモニア排出の増加による大気中酸性度の低下が促進の要因であると考えられる。このように、硫酸の三酸素同位体組成の分析によって、SO2排出規制にも関わらず硫酸エアロゾルの減少が鈍化するケミカルフィードバック機構の要因が、大気酸性度の低下によるSO2の液相O3酸化の促進であることが特定された。
  • Spatial Distribution of the Input of Insoluble Particles Into the Surface of the Qaanaaq Glacier, Northwestern Greenland
    Sumito Matoba, Ryo Hazuki, Yutaka Kurosaki, Teruo Aoki
    Frontiers in Earth Science, 8, Frontiers Media SA, 11 Dec. 2020, [Peer-reviewed], [Lead author, Corresponding author]
    Scientific journal, From glaciological observations, we found spatial variation in the input of insoluble particles (ISP) on a glacier surface from atmospheric deposition and outcropping at the surface of the glacier by surface ablation at the ablation area of the Qaanaaq Ice Cap in northwestern Greenland. Possible sources of ISP input to the glacier surface were outcropping at the surface of the glacier by ablation at intermediate and low elevations, and from atmospheric deposition at high elevations. The annual atmospheric deposition of ISP was larger at high elevations than at intermediate and low elevations. The annual abundance of outcropping ISP was larger at intermediate elevations than at low elevations, where the annual ablation rate of the glacier surface was 1.5 times larger than at intermediate elevations. The ISP concentration in the glacier ice at intermediate sites was approximately 10 times larger than at low sites. The water stable isotopes of glacier ice at intermediate sites indicated that glacier ice at the intermediate sites did not form since the last glacial maximum, possibly the Holocene Thermal Maximum. Therefore, the accumulation of the ISP, which is outcropping at the intermediate site, occurred at high elevations after Holocene Thermal Maximum., 12352088
  • アイスコア—極域海氷—海洋エアロゾル研究の新展開
    飯塚芳徳, 的場澄人, 宮﨑雄三
    大気化学研究, 44, Nov. 2020, [Peer-reviewed], [Corresponding author]
    Japanese, Scientific journal, 30109798
  • Sources and behavior of monsoon air masses in the lowest-latitude region on the Tibetan Plateau, and their paleoclimatic implications
    Mitsugu Nishimura, Tetsuya Matsunaka, Junbo Wang, Sumito Matoba, Akane Tsushima, Liping Zhu, Yasuhiro Izutsu
    Palaeogeography, Palaeoclimatology, Palaeoecology, 554, 109750, 109750, Elsevier BV, Sep. 2020, [Peer-reviewed], [Internationally co-authored], [International Magazine]
    English, Scientific journal
  • Temporal and spatial variabilities in surface mass balance at the EGRIP site, Greenland from 2009 to 2017
    Yuki Komuro, Fumio Nakazawa, Motohiro Hirabayashi, Kumiko Goto-Azuma, Naoko Nagatsuka, Wataru Shigeyama, Sumito Matoba, Tomoyuki Homma, Jørgen Peder Steffensen, Dorthe Dahl-Jensen
    Polar Science, 27, 100568, 100568, Elsevier BV, Aug. 2020, [Peer-reviewed]
    Scientific journal, 30109798
  • Reconstruction of sea ice concentration in northern Baffin Bay using deuterium excess in a coastal ice core from the northwestern Greenland Ice Sheet
    Yutaka Kurosaki, Sumito Matoba, Yoshinori Iizuka, Masashi Niwano, Tomonori Tanikawa, Takuto Ando, Akira Hori, Atsushi Miyamoto, Shuji Fujita, Teruo Aoki
    Journal of Geophysical Research: Atmospheres, 125, 16, American Geophysical Union (AGU), Aug. 2020, [Peer-reviewed]
    Scientific journal, 12352088
  • Ice core records of levoglucosan and dehydroabietic and vanillic acids from Aurora Peak in Alaska since the 1660s: a proxy signal of biomass-burning activities in the North Pacific Rim
    Ambarish Pokhrel, Kimitaka Kawamura, Bhagawati Kunwar, Kaori Ono, Akane Tsushima, Osamu Seki, Sumio Matoba, Takayuki Shiraiwa
    Atmospheric Chemistry and Physics, 20, 1, 597, 612, Copernicus GmbH, 17 Jan. 2020, [Peer-reviewed]
    English, Scientific journal, Abstract. A 180 m long (343 years) ice core was drilled in the saddle of Aurora Peak
    in Alaska (63.52∘ N, 146.54∘ W; elevation: 2825 m) and
    studied for biomass-burning tracers. Concentrations of levoglucosan and
    dehydroabietic and vanillic acids exhibit multidecadal variability, with
    higher spikes in 1678, 1692, 1695, 1716, 1750, 1764, 1756, 1834, 1898,
    1913, 1966 and 2005 CE. Historical trends of these compounds showed
    enhanced biomass-burning activities in the deciduous broadleaf forests,
    boreal conifer forests, and/or tundra woodland and mountain ecosystems before
    the 1830s and after the Great Pacific Climate Shift (GPCS). The gradually
    elevated level of dehydroabietic acid after the GPCS is similar to
    p-hydroxybenzoic acid (p-HBA) from the Svalbard ice core, suggesting common
    climate variability in the Northern Hemisphere. The periodic cycle of
    levoglucosan, which seemed to be associated with the Pacific Decadal
    Oscillation (PDO), may be more involved with the long-range atmospheric
    transport than other species. These compounds showed significant
    correlations with global lower-tropospheric temperature anomalies (GLTTAs).
    The relations of the biomass-burning tracers with the PDO and GLTTA in this
    study suggest that their emission, frequency and deposition are controlled
    by the climate-driven forces. In addition, historical trends of
    dehydroabietic and vanillic acids (burning products of resin and lignin,
    respectively) from our ice core demonstrate the Northern Hemispheric
    connections to the common source regions as suggested from other ice core
    studies from Svalbard, Akademii Nauk and Tunu Greenland in the Northern
    Hemisphere.
  • Inclusions in ice layers of SIGMA-A ice core, northwestern Greenland
    Kawakami Kaoru, Iizuka Yoshinori, Matoba Sumito, Aoki Teruo, Sugiyama Shin, Ando Takuto
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2020, 66, 66, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2020
    Japanese
  • ArCS II Cryosphere Research 3 “Water and material circulations in seasonal sea ice regions and their impacts on environment in the Arctic”
    Matoba Sumito, Iizuka Yoshinori, Miyazaki Yuzo, Suzuki Toshitaka, Hattori Shohei, Uemura Ryu, Hara Keiichiro, Oshima Naga, Yamasaki Tetsuhide, Aoki Teruo
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2020, 111, 111, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2020
    Japanese
  • Sulfate aerosol composition and flux during 1970’s derived from the SE-Dome ice core, Greenland
    Iizuka Yoshinori, Uemura Ryu, Matsui Hitoshi, Oshima Naga, Matoba Sumito
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2020, 67, 67, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2020
    Japanese
  • Atmospheric sea-salt and halogen cycles in the Antarctic
    Keiichiro Hara, Kazuo Osada, Masanori Yabuki, Sumito Matoba, Motohiro Hirabayashi, Shuji Fujita, Fumio Nakazawa, Takashi Yamanouchi
    Environmental Science: Processes & Impacts, 22, 10, 2003, 2022, Royal Society of Chemistry (RSC), 2020, [Peer-reviewed]
    Scientific journal,

    Atmospheric sea-salt and halogen cycles play important roles in atmospheric science and chemistry including cloud processes and oxidation capacity in the Antarctic troposphere.

  • Effects of snow grain shape and mixing state of snow impurity on retrieval of snow physical parameters from ground-based optical instrument
    Tanikawa, T, K. Kuchiki, T. Aoki, H. Ishimoto, A. Hachikubo, M. Niwano, M. Hosaka, S. Matoba, Y. Kodama, Y. Iwata, K. Stamnes
    Journal of Geophysical Researh, 125, 15, accepted, American Geophysical Union (AGU), 2020, [Peer-reviewed]
    Scientific journal
  • Assessment for paleoclimatic utility of biomass burning tracers in SE-Dome ice core, Greenland
    Fahmida Parvin, Osamu Seki, Koji Fujita, Yoshinori Iizuka, Sumito Matoba, Takuto Ando, Ken Sawada
    Atmospheric Environment, 196, 86, 94, Jan. 2019, [Peer-reviewed]
    English, Scientific journal, © 2018 The Authors We provide continuous records of biomass burning molecular tracers (levoglucosan and dehydroabietic acid) in a Greenland ice core collected from the Southeastern Dome (the SE-Dome ice core) over the past several decades to assess the paleoclimatic utility of these tracers in Greenland ice cores. An air mass backward-trajectory analysis indicates that eastern Canada is likely the primary source region of the biomass burning tracers. Comparisons of levoglucosan and dehydroabietic acid data in the SE-Dome ice core and area burned (vegetation fire) events in Canada suggests that the biomass burning tracers in the ice core document most of the pronounced biomass burning events in eastern Canada over the past several decades, confirming that analyses of biomass burning molecular tracers in Greenland ice cores are useful to reconstruct the frequency of significant biomass burning events in a local region. However, our study also highlights that the wind pattern when the biomass burning occurs is decisive for the registration of a biomass burning event in an ice core even though long-term changes in the wind regime associated with decadal-scale climate oscillations do not significantly influence the transport and deposition of biomass burning tracers on the Greenland ice sheet.
  • Seasonal variations and temporal trends of black carbon and dust in northwest Greenland over the past 350 years
    Goto-Azuma Kumiko, Matoba Sumito, Aoki Teruo, Moteki Nobuhiro, Ohata Sho, Mori Tatshuhiro, Koike Makoto, Komuro Yuki, Tsushima Akane, Nagatsuka Naoko, Shiegmaya Wataru, Ogawa-Tsukagawa Yoshimi, Fujita Koji, Kondo Yutaka, Remi Dallmayr, Hirabayashi Motohiro, Ogata Jun, Kitamura Kyotaro, Kawamura Kenji, Motoyama Hideaki
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2019, 82, 82, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2019
    Japanese
  • Glaciological traverse across the Southern Patagonian Icefield
    Masahiro MINOWA, Marius SCHAEFER, Pedro SKVARCA, Sumito MATOBA, Guisella GACITÚA
    Bulletin of Glaciological Research, 37, 0, 47, 56, Japanese Society of Snow and Ice, 2019, [Peer-reviewed]
    English, Scientific journal, To better understand the temporal variation of the ice surface elevation and the spatio-temporal variation of snow accumulation in the accumulation area of the Southern Patagonian Icefield, we carried out a glaciological traverse in October 2018. This included measurements of surface elevation, firn layers, and sampling of snow in the accumulation areas of Glaciar Viedma and Glaciar Pio XI. The main results from the traverse are: i) during the period of 2000-2018 the surface elevation in the accumulation area of Glaciar Viedma decreased by 1.7 m a(-1), but increased at Glaciar Pio XI by 0.4 m a(-1), ii) ground-penetrating radar revealed numerous firn layers with a continuous water aquifer at 20-40 m depth, iii) the water isotope ratio of surface snow samples varied with wind direction. Repeating the traverse in the area will provide an opportunity to answer questions about the contrasting glacier behavior and the snow accumulation rate, a necessary step to make reliable projections of future glacier behavior in Patagonia.
  • Open-sea and sea-ice fluctuations in nearshore Beaufort Sea during the last deglaciation derived from ion concentrations in ice wedge               
    Iizuka, Y, C. Miyamoto, S. Matoba, G. Iwahana, K. Horiuchi, Y. Takahashi, N. Kanna, K. Suzuki, H. Ohno
    Earth and Planetary Science Letter, 515, 58, 66, 2019, [Peer-reviewed]
    English, Scientific journal
  • Ion concentrations in ice wedges: An innovative approach to reconstruct past climate variability
    Iizuka Yoshinori, Miyamoto Chihiro, Matoba Sumito, Iwahana Go, Horiuchi Kazuho, Takahashi Yoshio, Kanna Naoya, Suzuki Koji, Ohno Hiroshi
    Earth and Planetary Science Letters, 515, 58, 66, 2019, [Peer-reviewed]
    Scientific journal, © 2019 Elsevier B.V. For atmospheric gases and aerosols, snow and ice provide a useful archive of paleoenvironmental history. In the northern hemisphere, this archive has been largely limited to Greenland ice, but promising pioneering work has been done recently using chronology of an ice wedge in Barrow, northern Alaska. Here, we investigate past aerosols at the same ice-wedge sampling site, reconstructing the sea-ice fluctuations in the adjacent Beaufort Sea during the Bølling/Allerød (BA) and Younger Dryas (YD) periods. We confirm the integrity of methanesulfonate ion (MS − ) concentrations in the BIWS as marine proxies, and then find that the ice wedge has a high MS − concentration through the beginning (coldest) YD periods. The high MS − concentration indicates that even during the coldest YD periods (12,900–12,700 yrBP), the near-shore region in the Alaskan Beaufort Sea near Barrow may not have been completely filled by permanent sea ice.
  • Water stable isotope analysis of SIGMA-A ice core 2017 in north western part of Greenland Ice Sheet
    Yutaka Kurosaki, Sumito Matoba, Yoshinori Iizuka, Shin Sugiyama, Takuto Ando, Teruo Aoki
    Annual Report on Snow and Ice Studies in Hokkaido, 37, 91, 94, Sep. 2018
    Japanese
  • NHM-SMAP: Spatially and temporally high-resolution nonhydrostatic atmospheric model coupled with detailed snow process model for Greenland Ice Sheet
    Masashi Niwano, Teruo Aoki, Akihiro Hashimoto, Sumito Matoba, Satoru Yamaguchi, Tomonori Tanikawa, Koji Fujita, Akane Tsushima, Yoshinori Iizuka, Rigen Shimada, Masahiro Hori
    Cryosphere, 12, 2, 635, 655, Copernicus GmbH, 23 Feb. 2018, [Peer-reviewed]
    English, Scientific journal, To improve surface mass balance (SMB) estimates for the Greenland Ice Sheet (GrIS), we developed a 5ĝ€̄km resolution regional climate model combining the Japan Meteorological Agency Non-Hydrostatic atmospheric Model and the Snow Metamorphism and Albedo Process model (NHM-SMAP) with an output interval of 1ĝ€̄h, forced by the Japanese 55-year reanalysis (JRA-55). We used in situ data to evaluate NHM-SMAP in the GrIS during the 2011-2014 mass balance years. We investigated two options for the lower boundary conditions of the atmosphere: an offline configuration using snow, firn, and ice albedo, surface temperature data from JRA-55, and an online configuration using values from SMAP. The online configuration improved model performance in simulating 2ĝ€̄m air temperature, suggesting that the surface analysis provided by JRA-55 is inadequate for the GrIS and that SMAP results can better simulate physical conditions of snow/firn/ice. It also reproduced the measured features of the GrIS climate, diurnal variations, and even a strong mesoscale wind event. In particular, it successfully reproduced the temporal evolution of the GrIS surface melt area extent as well as the record melt event around 12 July 2012, at which time the simulated melt area extent reached 92.4ĝ€̄%. Sensitivity tests showed that the choice of calculation schemes for vertical water movement in snow and firn has an effect as great as 200ĝ€̄Gtĝ€̄year-1 in the GrIS-wide accumulated SMB estimates
    a scheme based on the Richards equation provided the best performance.
  • A 60 Year Record of Atmospheric Aerosol Depositions Preserved in a High-Accumulation Dome Ice Core, Southeast Greenland
    Yoshinori Iizuka, Ryu Uemura, Koji Fujita, Shohei Hattori, Osamu Seki, Chihiro Miyamoto, Toshitaka Suzuki, Naohiro Yoshida, Hideaki Motoyama, Sumito Matoba
    Journal of Geophysical Research: Atmospheres, 123, 1, 574, 589, 16 Jan. 2018, [Peer-reviewed]
    English, Scientific journal, ©2017. American Geophysical Union. All Rights Reserved. The Southeastern Greenland Dome (SE-Dome) has both a high elevation and a high accumulation rate (1.01 m we yr−1), which are suitable properties for reconstructing past environmental changes with a high time resolution. For this study, we measured the major ion fluxes in a 90 m ice core drilled from the SE-Dome region in 2015 and present the records of annual ion fluxes from 1957 to 2014. From 1970 to 2010, the trend of nonsea-salt (nss) SO42− flux decreases, whereas that for NH4+ increases, tracking well with the anthropogenic SOx and NH3 emissions mainly from North America. The result suggests that these fluxes reflect histories of the anthropogenic SOx and NH3 emissions. In contrast, the decadal trend of NO3− flux differs from the decreasing trend of anthropogenic NOx emissions. Although the cause of this discrepancy remains unclear, it may be related to changes in particle formation processes and chemical scavenging rates caused by an increase in sea salt and dust and/or a decrease in nssSO42−. We also find a high average NO3− flux (1.13 mmol m−2 yr−1) in the ice core, which suggests a negligible effect from postdepositional NO3− loss. Thus, the SE-Dome region is an excellent location for reconstructing nitrate fluxes. Over a decadal time scale, our NO3− flux record is similar to those from other ice cores in Greenland high-elevation sites, suggesting that NO3− concentration records from these ice cores are reliable.
  • Field activites at the SIGMA-A site, northwestern Greenland Ice Sheet, 2017
    Matoba, S, M. Niwano, T. Tanikawa, Y. Iizuka, T. Yamasaki, Y. Kurosaki, A. Hashimoto, M. Hosaka, S. Sugiyama
    Bullet. Glaciol. Res., 36, 0, 15, 22, Japanese Society of Snow and Ice, 2018, [Peer-reviewed]
    English, Scientific journal
  • Effect of snow impurities on radiation budget in Sapporo
    Hirozawa Yoichiro, Aoki Teruo, Niwano Masashi, Matoba Sumito, Kodama Yuji, Tanikawa Tomonori
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2018, 203, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2018
    Japanese
  • Past 60 years changes in oxidation pathways of tropospheric sulfur from triple oxygen isotopic composition of sulfate preserved in SE-Dome ice core
    Hattori Shohei, Iizuka Yoshinori, Uemura Ryu, Suzuki Nozomi, Tsuruta Asuka, Ishino Sakiko, Fujita Koji, Matoba Sumito, Yoshida Naohiro
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 65, 12, GEOCHEMICAL SOCIETY OF JAPAN, 2018
    Japanese, グリーンランドの氷床コアは北アメリカやヨーロッパ由来の大気が由来し、過去のエアロゾル動態を復元する貴重な環境媒体である。産業革命以降の人間活動の増大に伴い、大気中に放出される硫黄及び窒素酸化物の濃度が上昇し、1970年以降に北アメリカ、ヨーロッパで排出が抑制された。事実、氷床コア中の硫酸濃度の減少がSO2排出量の減少と対応していることが知られている。本研究では、グリーンランド南東ドーム(SE-Dome)で採取された約90 m、60年分のアイスコアを用い、時間解像度3~6年で硫酸の三酸素同位体組成を分析した。
  • High-resolution analysis of black carbon in an ice core drilled at Northwest Greenland
    Goto-Azuma Kumiko, Matoba Sumito, Kadota Moe, Aoki Teruo, Moteki Nobuhiro, Ohata Sho, Mori Tatshuhiro, Koike Makoto, Komuro Yuki, Tsushima Akane, Nagatsuka Naoko, Ogawa-Tsukagawa Yoshimi, Fujita Koji, Kondo Yutaka, Dallmayr Remi, Hirabayashi Motohiro, Ogata Jun, Kitamura Kyotaro, Kawamura Kenji, Motoyama Hideaki
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2018, 216, 216, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2018
    Japanese
  • バフィン湾周辺の環境がグリーンランド北西部の降雪中のd-excessと化学成分に与える影響
    黒﨑豊, 的場澄人, 飯塚芳徳, 庭野匡思, 谷川朋範, 青木輝夫
    雪氷, 80, 6, 515, 529, 2018, [Peer-reviewed]
  • Seasonal-Scale Dating of a Shallow Ice Core From Greenland Using Oxygen Isotope Matching Between Data and Simulation
    Ryoto Furukawa, Ryu Uemura, Koji Fujita, Jesper Sjolte, Kei Yoshimura, Sumito Matoba, Yoshinori Iizuka
    JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 122, 20, 10873, 10887, AMER GEOPHYSICAL UNION, Oct. 2017, [Peer-reviewed]
    English, Scientific journal, A precise age scale based on annual layer counting is essential for investigating past environmental changes from ice core records. However, subannual scale dating is hampered by the irregular intraannual variabilities of oxygen isotope (delta O-18) records. Here we propose a dating method based on matching the delta O-18 variations between ice core records and records simulated by isotope-enabled climate models. We applied this method to a new delta O-18 record from an ice core obtained from a dome site in southeast Greenland. The close similarity between the delta O-18 records from the ice core and models enables correlation and the production of a precise age scale, with an accuracy of a few months. A missing delta O-18 minimum in the 1995/1996 winter is an example of an indistinct delta O-18 seasonal cycle. Our analysis suggests that the missing delta O-18 minimum is likely caused by a combination of warm air temperature, weak moisture transport, and cool ocean temperature. Based on the age scale, the average accumulation rate from 1960 to 2014 is reconstructed as 1.02 m yr(-1) in water equivalent. The annual accumulation rate shows an increasing trend with a slope of 3.6 mm yr(-1), which is mainly caused by the increase in the autumn accumulation rate of 2.6 mm yr(-1). This increase is likely linked to the enhanced hydrological cycle caused by the decrease in Arctic sea ice area. Unlike the strong seasonality of precipitation amount in the ERA reanalysis data in the southeast dome region, our reconstructed accumulation rate suggests a weak seasonality.
  • Frost flowers and sea-salt aerosols over seasonal sea-ice areas in northwestern Greenland during winter-spring
    Keiichiro Hara, Sumito Matoba, Motohiro Hirabayashi, Tetsuhide Yamasaki
    ATMOSPHERIC CHEMISTRY AND PHYSICS, 17, 13, 8577, 8598, COPERNICUS GESELLSCHAFT MBH, Jul. 2017, [Peer-reviewed]
    English, Scientific journal, Sea salts and halogens in aerosols, frost flowers, and brine play an important role in atmospheric chemistry in polar regions. Simultaneous sampling and observations of frost flowers, brine, and aerosol particles were conducted around Siorapaluk in northwestern Greenland during December 2013 to March 2014. Results show that water-soluble frost flower and brine components are sea-salt components (e.g., Na+, Cl-, Mg2+, K+, Ca2+, Br-, and iodine). Concentration factors of sea-salt components of frost flowers and brine relative to seawater were 1.14-3.67. Sea-salt enrichment of Mg2+, K+, Ca2+, and halogens (Cl-, Br-, and iodine) in frost flowers is associated with sea-salt fractionation by precipitation of mirabilite and hydrohalite. High aerosol number concentrations correspond to the occurrence of higher abundance of sea-salt particles in both coarse and fine modes, and blowing snow and strong winds. Aerosol number concentrations, particularly in coarse mode, are increased considerably by release from the sea-ice surface under strong wind conditions. Sulfate depletion by sea-salt fractionation was found to be limited in sea-salt aerosols because of the presence of non-sea-salt (NSS) SO42-. However, coarse and fine sea-salt particles were found to be rich in Mg. Strong Mg enrichment might be more likely to proceed in fine sea-salt particles. Magnesium-rich sea-salt particles might be released from the surface of snow and slush layer (brine) on sea ice and frost flowers. Mirabilite-like and ikaite-like particles were identified only in aerosol samples collected near new sea-ice areas. From the field evidence and results from earlier studies, we propose and describe sea-salt cycles in seasonal sea-ice areas.
  • Global warming response of snowpack at mountain range in northern Japan estimated using multiple dynamically downscaled data
    Yuta Katsuyama, Masaru Inatsu, Kazuki Nakamura, Sumito Matoba
    COLD REGIONS SCIENCE AND TECHNOLOGY, 136, 62, 71, ELSEVIER SCIENCE BV, Apr. 2017, [Peer-reviewed]
    English, Scientific journal, We estimate the response of snowpack to global warming along with the uncertainty of the snowpack change by using a combination of multiple general-circulation models (GCMs), a single regional atmospheric model, and a one-dimensional multi-layered snowpack model. The target site is Mt. Annupuri in Kutchan, Hokkaido, Japan. The forcing of the snowpack model is taken from dynamically downscaled data from GCMs for the present climate and GCMs in a decade when the global-mean temperature has increased by 2 K from present conditions. The results show that global warming would decrease the monthly-mean snow depth throughout the winter season. Other salient features are the decrease of snow depth by 60 cm with maximum uncertainty of 20 cm at the beginning of the snow ablation period, the occurrence of the snow-depth peak a month earlier, and the dominance of melt forms in an earlier season. The ratio of melt forms for all snowpack layers increases with little uncertainty before the snow ablation period. The ratio of hoar does not change much, even though the air temperature increases. The uncertainty in snowpack evaluation is also discussed. (C) 2017 Elsevier B.V. All rights reserved.
  • グリーンランド南東ドームにおける浅層掘削と初期物理解析               
    飯塚芳徳, 的場澄人, 藤田秀二, 新堀邦夫, 山崎哲秀, 宮本淳, 堀彰, 斉藤健, 古川崚仁, 杉山慎, 青木輝夫
    低温科学, 75, 45, 52, Mar. 2017
    Japanese
  • Surface mass balance variations in a maritime area of the northwestern Greenland Ice Sheet
    的場澄人, 山口悟, 對馬あかね, 青木輝夫, 杉山慎
    低温科学, 75, 37, 44, Mar. 2017
    Japanese, Research institution
  • A firn densification process in the high accumulation dome of southeastern Greenland
    Yoshinori Iizuka, Atsushi Miyamoto, Akira Hori, Sumito Matoba, Ryoto Furukawa, Takeshi Saito, Shuji Fujita, Motohiro Hirabayashi, Satoru Yamaguchi, Koji Fujita, Nozomu Takeuchi
    ARCTIC ANTARCTIC AND ALPINE RESEARCH, 49, 1, 13, 27, INST ARCTIC ALPINE RES, Feb. 2017, [Peer-reviewed]
    English, Scientific journal, We examine a firn core from a dome in southeast Greenland that exhibits distinct firn densification. The ice was-20.9 degrees C at 20 m depth, and the core gives an average accumulation rate of 1.0 m w.e. yr(-1) in water equivalent. However, the close-off density of 830 kg m(-3) occurs at 83.4-86.8 m depth, which is about 20-m shallower than that obtained from two empirical models. Where the density p > 750 kg m(-3), the densification appears faster than that from the empirical models. As a result, compared to the empirical coefficient, the actual compactive viscosity coefficient is nonlinear and decreases at p > 750 kg m(-3), indicating that the fun with a higher density is softer than that from the empirical result. We argue here that the high accumulation rate creates a high overburden pressure in a short time. Thus, the relative softness of the firn may arise from (1) there being not enough time to form bonds between grains as strong as those in a lower accumulation-rate area, and similarly, (2) the dislocation density in the firn being relatively high.
  • An Unreported Asian Dust (Kosa) Event in Hokkaido, Japan: A Case Study of 7 March 2016
    Teppei J. Yasunari, Masashi Niwano, Yasushi Fujiyoshi, Atsushi Shimizu, Masamitsu Hayasaki, Teruo Aoki, Arlindo M. da Silva, Brent N. Holben, Sumito Matoba, Naoto Murao, Sadamu Yamagata, Kyu-Myong Kim
    SOLA, 13, 96, 101, METEOROLOGICAL SOC JAPAN, 2017, [Peer-reviewed]
    English, Scientific journal, Monitoring particulate matter is essential to alert the public about health risks. The Terra/MODIS true color image clearly captured a yellow band over Hokkaido prefecture in Japan on 7 March 2016. We investigated whether this event was an Asian dust (Kosa) transport or not with the ground-based observations in Sapporo and Takikawa in Hokkaido and NASA's MERRA-2 re-analysis data. The timing of increased particle number concentrations (PNCs; greater than 0.5 mu m) was clearly measured by a low-cost aerosol sensor at Sapporo and Takikawa in the early afternoon. For this particle size range, the PNC by this aerosol sensor had greater agreement with another commercial instrument for the 1-hourly mean data. The lidar data at Takikawa and NASA's AERONET at Sapporo also implied the increased dust particles (i.e., dominance of non-spherical and coarse particles, respectively), which supported that the PNC increase was due to the dust transport. The hourly PM2.5 data in Sapporo significantly increased in the evening rather than around the noon to early afternoon. We concluded that this event was judged as an Asian dust (Kosa) event in Hokkaido starting from the early afternoon, which was, however, not reported by Japan Meteorological Agency (JMA) based on their visible observations.
  • The past 60 years variation of nitrogen isotopic composition of nitrate preserved in SE-Dome site, southeastern Greenland Ice Sheet
    Tsuruta Asuka, Hattori Shohei, Iizuka Yoshinori, Fujita Koji, Uemura Ryu, Matoba Sumito, Yoshida Naohiro
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 64, 19, 19, GEOCHEMICAL SOCIETY OF JAPAN, 2017
    Japanese,

  • The past 60 years variations of sources and formation pathways of nitrate preserved in SE-Dome site, southeastern Greenland Ice Sheet
    Tsuruta Asuka, Hattori Shohei, Iizuka Yoshinori, Fujita Koji, Uemura Ryu, Matoba Sumito, Yoshida Naohiro
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, 120, 120, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2017
    Japanese
  • Seasonal scale dating of a shallow ice core from Greenland using oxygen isotope matching between data and simulation
    Furukawa Ryoto, Uemura Ryu, Fujita Koji, Sjolte Jesper, Yoshimura Kei, Matoba Sumito, Iizuka Yoshinori
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 64, 18, 18, GEOCHEMICAL SOCIETY OF JAPAN, 2017
    Japanese,

  • Understanding variation trend of δ17O and 17O-excess in an ice core drilled at the SIGMA-D site
    Tsushima Akane, Gkinis Vasileios, Goto-Azuma Kumiko, Matoba Sumito, Nagatsuka Naoko, Motoyama Hideaki, Fujita Koji, Aoki Teruo
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, 155, 155, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2017
    Japanese
  • Variations in mineralogy of dust in ice core obtained from Northwestern Greenland Ice Sheet
    Nagatsuka Naoko, Goto-Azuma Kumiko, Tsushima Akane, Motoyama Hideaki, Matoba Sumito, Fujita Koji, Yamasaki Tetsuhide, Onuma Yukihiko, Minowa Masahiro, Aoki Teruo
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, 119, 119, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2017
    Japanese
  • Field activities at the northwestern Greenland Ice Sheet (SIGMA-A site) in 2017
    Matoba Sumito, Niwano Masashi, Tanikawa Tomonori, Iizuka Yoshinori, Yamasaki Tetsuhide, Kurosaki Yutaka, Aoki Teruo, Hashimoto Akihiro, Hosaka Masahiro, Sugiyama Shin
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, 288, 288, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2017
    Japanese
  • Effect of snow impurities on albedo and radiative forcing in Sapporo
    Hirozawa Yoichiro, Aoki Teruo, Niwano Masashi, Matoba Sumito, Kodama Yuji, Tanikawa Tomonori
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, 6, 6, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2017
    Japanese
  • The characteristics of snowpack at the beginning of melting season at Qaanaaq ice cap, northwestern Greenland
    Hazuki Ryo, Kurosaki Yutaka, Matoba Sumito, Sugiyama Shin
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, 190, 190, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2017
    Japanese
  • Data publication of snow cover and meteorological observations conducted at Institute of Low Temperature Science, Hokkaido University in Sapporo
    Sumito Matoba, T. Aoki, M. Niwano, K. Kuchiki, Y. Kodama, S. Yamaguchi
    Annual report on Snow and Ice Studies in Hokkaido, 35, 135, 136, Sep. 2016
    Japanese, Symposium
  • Ice core records of monoterpene- and isoprene-SOA tracers from Aurora Peak in Alaska since 1660s: Implication for climate change variability in the North Pacific Rim
    Ambarish Pokhrel, Kimitaka Kawamura, Kaori Ono, Osamu Seki, Pingqing Fu, Sumio Matoba, Takayuki Shiraiwa
    ATMOSPHERIC ENVIRONMENT, 130, 105, 112, PERGAMON-ELSEVIER SCIENCE LTD, Apr. 2016, [Peer-reviewed]
    English, Scientific journal, Monoterpene and isoprene secondary organic aerosol (SOA) tracers are reported for the first time in an Alaskan ice core to better understand the biological source strength before and after the industrial revolution in the Northern Hemisphere. We found significantly high concentrations of monoterpene- and isoprene-SOA tracers (e.g., pinic, pinonic, and 2-methylglyceric acids, 2-methylthreitol and 2-methylerythritol) in the ice core, which show historical trends with good correlation to each other since 1660s. They show positive correlations with sugar compounds (e.g., mannitol, fructose, glucose, inositol and sucrose), and anti-correlations with alpha-dicarbonyls (glyoxal and methylglyoxal) and fatty acids (e.g., C-18:1) in the same ice core. These results suggest similar sources and transport pathways for monoterpene- and isoprene-SOA tracers. In addition, we found that concentrations of C-5-alkene triols (e.g., 3-methyl-2,3,4-trihydroxy-1-butene, cis-2-methyl 1,3,4-trihydroxy-1-butene and trans-2-methyl-1,3,4-trihydroxy-1-butene) in the ice core have increased after the Great Pacific Climate Shift (late 1970s). They show positive correlations with a-dicarbonyls and fatty acids (e.g., C-18:1) in the ice core, suggesting that enhanced oceanic emissions of biogenic organic compounds through the marine boundary layer are recorded in the ice core from Alaska. Photochemical oxidation process for these monoterpene- and isoprene-/sesquiterpene-SOA tracers are suggested to be linked with the periodicity of multi-decadal climate oscillations and retreat of sea ice in the Northern Hemisphere. (C) 2015 Elsevier Ltd. All rights reserved.
  • Seasonal variations in the major chemical species of snow at the South East Dome in Greenland
    Ikumi Oyabu, Sumito Matoba, Tetsuhide Yamasaki, Moe Kadota, Yoshinori Iizuka
    POLAR SCIENCE, 10, 1, 36, 42, ELSEVIER SCIENCE BV, Mar. 2016, [Peer-reviewed]
    English, Scientific journal, We analyze snow-pit samples collected in May 2015 at the South East Dome (SE Dome) on the Greenland ice sheet. The analysis includes high-resolution records of delta D and delta O-18, as well as the major ions, CH3SO3-, Cl-, NO3-, SO42-, Na+, NH4+, K+, Ma(2+), and Ca2+. We find that the 3.55-m snow pit recorded temperature and aerosol proxies back to summer or autumn of 2014. This indicates a higher accumulation rate than those at other major drilling sites in Greenland. Due to this high accumulation rate, ion concentrations except Na+ are lower than those typical of the central Greenland ice sheet. Concerning seasonal variability, the Na+, Cl-, Ca2+, Mg2+, and NO3- vary similarly to other sites in Greenland, with the Na+ and Cl- peaking in winter to early spring, Ca2+ peaking in spring, Mg2+ peaking in winter to spring, and NO3- towards a peak in summer while showing smaller peaks in winter to spring. The NH4+ increased in spring, and SO42- increased in autumn to winter at SE Dome. On the other hand, the seasonal trend in the Cl-/Na+ ratio differs from those in the inland region. As we did not fully recover one seasonal cycle, some seasonal peaks may have been missed. (C) 2016 Elsevier B.V. and NIPR. All rights reserved.
  • Variability of black carbon in Greenland during the past 350 years at the SIGMA-D site - Preliminary results from Continuous Flow Analysis –
    Goto-Azuma Kumiko, Matoba Sumito, Kadota Moe, Aoki Teruo, Moteki Nobuhiro, Ohata Sho, Mori Tatshuhiro, Koike Makoto, Komuro Yuki, Tsushima Akane, Nagatsuka Naoko, Ogawa-Tsukagawa Yoshimi, Yutaka Yutaka, Dallmayr Remi, Hirabayashi Motohiro, Ogata Jun, Kitamura Kyotaro, Kawamura Kenji, Motoyama Motoyama
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2016, 190, 190, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2016
    Japanese
  • Temporal variation in iron flux deposition onto the northern North Pacific reconstructed from an ice core drilled at Mount Wrangell, Alaska
    Hirotaka Sasaki, Sumito Matoba, Takayuki Shiraiwa, Carl S. Benson
    Scientific Online Letters on the Atmosphere, 12, 287, 290, Meteorological Society of Japan, 2016, [Peer-reviewed]
    English, Scientific journal, To quantify the atmospheric iron deposition on the northern North Pacific region, we measured concentrations of iron in ice cores drilled at Mount Wrangell, Alaska, in 2003 and 2004. The iron concentration profile from 1981 to 2003 showed seasonal peaks each spring. This variation was similar to the seasonal variation in the concentration of mineral dust in the atmosphere in the North Pacific region. The annual iron fluxes calculated from the ice core records ranged from 3.2 to 27.0 mg m-2 yr-1, and the temporal variation in the iron flux was significantly correlated with the frequency of severe dust storms occurrence on the East Asian continent (r = 0.65, p <
    0.05) and the total number of Kosa days observed in Japan (r = 0.64-0.66, p <
    0.05), but not with the precipitation amount in Alaska. We concluded that the amount of iron deposition onto the northern North Pacific is controlled mainly by the emission of dust from the east Asian continent and not by scavenging processes in Alaska.
  • Glaciological and meteorological observations at the SE-Dome site, southeastern Greenland Ice Sheet
    Yoshinori Iizuka, Sumito Matoba, Tetsuhide Yamasaki, Ikumi Oyabu, Moe Kadota, Teruo Aoki
    Bulletin of Glaciological Research, 34, 1, 1, 10, Japanese Society of Snow and Ice, 2016, [Peer-reviewed]
    English, Scientific journal, In order to understand 1) temporal variations of anthropogenic aerosols from European regions under the Icelandic low with high time resolution, and 2) the snow densification mechanism at the high accumulation dome in Greenland, we drilled a 90.45m ice core in a high accumulation area of the southeastern Greenland Ice Sheet. The drilling site (SE-Dome
    67.18°N, 36.37°W, 3170m a.s.l.) is located 185km north of the town of Tasiilaq in southeastern Greenland. We also conducted borehole temperature measurements. The temperature in the borehole was -20.9°C at a depth of 20m. In addition, we did snow-pit observations, aerosol sampling, snow sampling for chemical and physical analyses and meteorological observation. Air temperature and air pressure were on average -16.8°C and 667hPa during our stay. The aerosol concentration in the top surface 0.1m snow at SE-Dome in the spring of 2015 was lower than those of the other regions in Greenland, likely due to a highland dome of the ice sheet and/or dilution of mass flux by high snow accumulation.
  • Operation of the gas-adsorption type instrument for measuring snow SSA in a fieldwork
    八久保, 晶弘, 山口, 悟, 堀, 雅裕, 谷川, 朋範, 杉浦, 幸之助, 的場, 澄人, 庭野, 匡思, 朽木, 勝幸, 青木, 輝夫
    北海道の雪氷, 34, 34, 15, 18, 公益社団法人日本雪氷学会北海道支部, Sep. 2015
    Japanese, Scientific journal
  • Elemental carbon, organic carbon, and dust concentrations in snow measured with thermal optical and gravimetric methods: Variations during the 2007-2013 winters at Sapporo, Japan
    Katsuyuki Kuchiki, Teruo Aoki, Masashi Niwano, Sumito Matoba, Yuji Kodama, Kouji Adachi
    Journal of Geophysical Research, 120, 2, 868, 882, Wiley-Blackwell, 27 Jan. 2015, [Peer-reviewed]
    English, Scientific journal, The mass concentrations of light-absorbing snow impurities at Sapporo, Japan, were measured during six winters from 2007 to 2013. Elemental carbon (EC) and organic carbon (OC) concentrations were measured with the thermal optical method, and dust concentration was determined by filter gravimetric measurement. The measurement results using the different filters were compared to assess the filtration efficiency. Adding NH4H2PO4 coagulant to melted snow samples improved the collection efficiency for EC particles by a factor of 1.45. The mass concentrations of EC, OC, and dust in the top 2 cm layer ranged in 0.007-2.8, 0.01-13, and 0.14-260 ppmw, respectively, during the six winters. Themass concentrations and their short-term variations were larger in the surface than in the subsurface. The snow impurity concentrations varied seasonally
    that is, they remained relatively low during the accumulation season and gradually increased during the melting season. Although the surface snow impurities showed no discernible trend over the six winters, they varied from year to year, with a negative correlation between the snow impurity concentrations and the amount of snowfall. The surface snow impurities generally increased with the number of days elapsed since snowfall and showed a different rate for EC (1.44), OC (9.96), and dust (6.81). The possible processes causing an increase in surface snow impurities were dry deposition of atmospheric aerosols, melting of surface snow, and sublimation/evaporation of surface snow.
  • Glaciological and meteorological observations at the SIGMA-D site, northwestern Greenland Ice Sheet
    Matoba, S., Motoyama, H., Fujita, K., Yamasaki, T., Minowa, M., Onuma, Y., Komuro, Y., Aoki, T., Yamaguchi, S., Sugiyama, S., Enomoto, H.
    Bulletin of Glaciological Research, 33, 7, 14, 2015, [Peer-reviewed]
    English, Scientific journal
  • Numerical simulation of extreme snowmelt observed at the SIGMA-A site, northwest Greenland, during summer 2012
    M. Niwano, T. Aoki, S. Matoba, S. Yamaguchi, T. Tanikawa, K. Kuchiki, H. Motoyama
    CRYOSPHERE, 9, 3, 971, 988, COPERNICUS GESELLSCHAFT MBH, 2015, [Peer-reviewed]
    English, Scientific journal, The surface energy balance (SEB) from 30 June to 14 July 2012 at site SIGMA (Snow Impurity and Glacial Microbe effects on abrupt warming in the Arctic)-A, (78 degrees 03'N, 67 degrees 38'W; 1490 ma.s.l.) on the northwest Greenland Ice Sheet (GrIS) was investigated by using in situ atmospheric and snow measurements as well as numerical modeling with a one-dimensional multi-layered physical snowpack model called SMAP (Snow Metamorphism and Albedo Process). At SIGMA-A, remarkable near-surface snowmelt and continuous heavy rainfall (accumulated precipitation between 10 and 14 July was estimated to be 100 mm) were observed after 10 July 2012. Application of the SMAP model to the GrIS snowpack was evaluated based on the snow temperature profile, snow surface temperature, surface snow grain size, and shortwave albedo, all of which the model simulated reasonably well. Above all, the fact that the SMAP model successfully reproduced frequently observed rapid increases in snow albedo under cloudy conditions highlights the advantage of the physically based snow albedo model (PBSAM) incorporated in the SMAP model. Using such data and model, we estimated the SEB at SIGMA-A from 30 June to 14 July 2012. Radiation-related fluxes were obtained from in situ measurements, whereas other fluxes were calculated with the SMAP model. By examining the components of the SEB, we determined that low-level clouds accompanied by a significant temperature increase played an important role in the melt event observed at SIGMA-A. These conditions induced a remarkable surface heating via cloud radiative forcing in the polar region.
  • Elemental carbon, organic carbon, and dust concentrations in snow measured with thermal optical and gravimetric methods: Variations during the 2007-2013 winters at Sapporo, Japan
    Katsuyuki Kuchiki, Teruo Aoki, Masashi Niwano, Sumito Matoba, Yuji Kodama, Kouji Adachi
    JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 120, 2, 868, 882, AMER GEOPHYSICAL UNION, Jan. 2015, [Peer-reviewed]
    English, Scientific journal, The mass concentrations of light-absorbing snow impurities at Sapporo, Japan, were measured during six winters from 2007 to 2013. Elemental carbon (EC) and organic carbon (OC) concentrations were measured with the thermal optical method, and dust concentration was determined by filter gravimetric measurement. The measurement results using the different filters were compared to assess the filtration efficiency. Adding NH4H2PO4 coagulant to melted snow samples improved the collection efficiency for EC particles by a factor of 1.45. The mass concentrations of EC, OC, and dust in the top 2cm layer ranged in 0.007-2.8, 0.01-13, and 0.14-260ppmw, respectively, during the six winters. The mass concentrations and their short-term variations were larger in the surface than in the subsurface. The snow impurity concentrations varied seasonally; that is, they remained relatively low during the accumulation season and gradually increased during the melting season. Although the surface snow impurities showed no discernible trend over the six winters, they varied from year to year, with a negative correlation between the snow impurity concentrations and the amount of snowfall. The surface snow impurities generally increased with the number of days elapsed since snowfall and showed a different rate for EC (1.44), OC (9.96), and dust (6.81). The possible processes causing an increase in surface snow impurities were dry deposition of atmospheric aerosols, melting of surface snow, and sublimation/evaporation of surface snow.
  • Validation of the SNOWPACK model using snow pit observation data
    Hirashima, H, Yamaguchi, S, Kosugi, K, Nemoto, M, Aoki, T, Matoba, S
    Seppyo, 77, 1, 5, 16, Jan. 2015, [Peer-reviewed]
    Japanese, Scientific journal
  • Reconstruction of recent climate change in Alaska from the Aurora Peak ice core, central Alaska
    A. Tsushima, S. Matoba, T. Shiraiwa, S. Okamoto, H. Sasaki, D. J. Solie, K. Yoshikawa
    CLIMATE OF THE PAST, 11, 2, 217, 226, COPERNICUS GESELLSCHAFT MBH, 2015, [Peer-reviewed]
    English, Scientific journal, A 180.17m ice core was drilled at Aurora Peak in the central part of the Alaska Range, Alaska, in 2008 to allow reconstruction of centennial-scale climate change in the northern North Pacific. The 10m depth temperature in the borehole was -2.2 degrees C, which corresponded to the annual mean air temperature at the drilling site. In this ice core, there were many melt-refreeze layers due to high temperature and/or strong insolation during summer seasons. We analyzed stable hydrogen isotopes (delta D) and chemical species in the ice core. The ice core age was determined by annual counts of delta D and seasonal cycles of Na+, and we used reference horizons of tritium peaks in 1963 and 1964, major volcanic eruptions of Mount Spurr in 1992 and Mount Katmai in 1912, and a large forest fire in 2004 as age controls. Here, we show that the chronology of the Aurora Peak ice core from 95.61m to the top corresponds to the period from 1900 to the summer season of 2008, with a dating error of +/- 3 years. We estimated that the mean accumulation rate from 1997 to 2007 (except for 2004) was 2.04mw.eq.yr(-1). Our results suggest that temporal variations in delta D and annual accumulation rates are strongly related to shifts in the Pacific Decadal Oscillation index (PDOI). The remarkable increase in annual precipitation since the 1970s has likely been the result of enhanced storm activity associated with shifts in the PDOI during winter in the Gulf of Alaska.
  • Ice core profiles of saturated fatty acids (C-12:0-C-30:0) and oleic acid (C-18:1) from southern Alaska since 1734 AD: A link to climate change in the Northern Hemisphere
    Ambarish Pokhrel, Kimitaka Kawamura, Osamu Seki, Sumio Matoba, Takayuki Shiraiwa
    ATMOSPHERIC ENVIRONMENT, 100, 202, 209, PERGAMON-ELSEVIER SCIENCE LTD, Jan. 2015, [Peer-reviewed]
    English, Scientific journal, An ice core drilled at Aurora Peak in southeast Alaska was analyzed for homologous series of straight chain fatty acids (C-12:0-C-30:0) including unsaturated fatty acid (oleic acid) using gas chromatography (GC/FID) and GC/mass spectrometry (GC/MS). Molecular distributions of fatty acids are characterized by even carbon number predominance with a peak at palmitic acid (C-16:0, av. 20.3 +/- SD. 29.8 ng/g-ice) followed by oleic acid (C-18:1, 19.6 +/- 38.6 ng/g-ice) and myristic acid (C-14:0, 15.3 +/- 21.9 ng/g-ice). The historical trends of short-chain fatty acids, together with correlation analysis with inorganic ions and organic tracers suggest that short-chain fatty acids (except for C-12:0 and C-15:0) were mainly derived from sea surface micro layers through bubble bursting mechanism and transported over the glacier through the atmosphere. This atmospheric transport process is suggested to be linked with Kamchatka ice core SD record from Northeast Asia and Greenland Temperature Anomaly (GTA). In contrast, long-chain fatty acids (C-20.0-C-30:0) are originated from terrestrial higher plants, soil organic matter and dusts, which are also linked with GTA. Hence, this study suggests that Alaskan fatty acids are strongly influenced by Pacific Decadal Oscillation/North Pacific Gyre Oscillation and/or extra tropical North Pacific surface climate and Arctic oscillation. We also found that decadal scale variability of C-18:1/C-18:0 ratios in the Aurora Peak ice core correlate with the Kamchatka ice core SD, which reflects climate oscillations in the North Pacific. This study suggests that photochemical aging of organic aerosols could be controlled by climate periodicity. (C) 2014 Elsevier Ltd. All rights reserved.
  • In situ measurements of polarization properties of snow surface under the brewster geometry in hokkaido, Japan, and northwest greenland ice sheet
    Tomonori Tanikawa, Masahiro Hori, Teruo Aoki, Akihiro Hachikubo, Katsuyuki Kuchiki, Masashi Niwano, Sumito Matoba, Satoru Yamaguchi, Knut Stamnes
    Journal of Geophysical Research, 119, 24, 13, 964, Wiley-Blackwell, 27 Dec. 2014, [Peer-reviewed]
    English, Scientific journal, Ground-based measurements of spectral degree of linear polarization (DLP) of various snow types were made during intensive field campaigns in a snowfield in Hokkaido, Japan, and on the northwest Greenland ice sheet in 2012. Spectral measurements were conducted under the solar zenith angle of approximately the Brewster angle in order to quantify the polarization properties of light reflected from snow. We obtained spectral DLPs for five different snow types in both field campaigns including precipitation particles, needles, surface hoar, melt forms, and melt freeze crust covering the snow surface. The measurements showed that in the visible region the spectral dependence of the DLP was small while in the near infrared region it increased with increasing snow grain size with some distinct local peaks. The angular dependence indicated that the DLP exhibited small angular dependence in the visible region while in the near-infrared region it exhibited large and broad peaks in the forward direction. Especially for the melt-freeze crust, the DLP approached 1.0 at wavelengths close to λ = 1.5 and 2.0 μm. These features can be explained by (1) the relative contribution of surface versus volume scattering to the reflected light, (2) the incident angle (solar zenith angle) of approximately the Brewster angle, and (3) the ratio between direct and diffuse components of the solar radiation incident on the snow surface. The spectral DLP was found to be quiet sensitive to the incident solar radiation and solar elevation as well as snow optical properties. Comparison between the spectral DLP and snow grain size obtained by snow pit work shows that the DLP for λ >
    1.5 μm was very sensitive to large snow grains close to the surface. This finding suggests that polarization measurements obtained from airborne/satellite polarimeters will be useful for surface snow grain size retrievals and help improve the accuracy of such retrievals based on the intensity-only measurements, especially for the large snow grain sizes.
  • In situ measurements of polarization properties of snow surface under the Brewster geometry in Hokkaido, Japan, and northwest Greenland ice sheet
    Tomonori Tanikawa, Masahiro Hori, Teruo Aoki, Akihiro Hachikubo, Katsuyuki Kuchiki, Masashi Niwano, Sumito Matoba, Satoru Yamaguchi, Knut Stamnes
    JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 119, 24, 13946, 13964, AMER GEOPHYSICAL UNION, Dec. 2014, [Peer-reviewed]
    English, Scientific journal, Ground-based measurements of spectral degree of linear polarization (DLP) of various snow types were made during intensive field campaigns in a snowfield in Hokkaido, Japan, and on the northwest Greenland ice sheet in 2012. Spectral measurements were conducted under the solar zenith angle of approximately the Brewster angle in order to quantify the polarization properties of light reflected from snow. We obtained spectral DLPs for five different snow types in both field campaigns including precipitation particles, needles, surface hoar, melt forms, and melt freeze crust covering the snow surface. The measurements showed that in the visible region the spectral dependence of the DLP was small while in the near infrared region it increased with increasing snow grain size with some distinct local peaks. The angular dependence indicated that the DLP exhibited small angular dependence in the visible region while in the near-infrared region it exhibited large and broad peaks in the forward direction. Especially for the melt-freeze crust, the DLP approached 1.0 at wavelengths close to lambda = 1.5 and 2.0 mu m. These features can be explained by (1) the relative contribution of surface versus volume scattering to the reflected light, (2) the incident angle (solar zenith angle) of approximately the Brewster angle, and (3) the ratio between direct and diffuse components of the solar radiation incident on the snow surface. The spectral DLP was found to be quiet sensitive to the incident solar radiation and solar elevation as well as snow optical properties. Comparison between the spectral DLP and snow grain size obtained by snow pit work shows that the DLP for lambda > 1.5.. m was very sensitive to large snow grains close to the surface. This finding suggests that polarization measurements obtained from airborne/satellite polarimeters will be useful for surface snow grain size retrievals and help improve the accuracy of such retrievals based on the intensity-only measurements, especially for the large snow grain sizes.
  • Wet and dry deposition of mineral dust particles in Japan: factors related to temporal variation and spatial distribution
    Osada, K., Ura, S., Kagawa, M., Mikami, M., Tanaka, T. Y., Matoba, S., Aoki, K., Shinoda, M., Kurosaki, Y., Hayashi, M., Shimizu, A., Uematsu, M.
    Atmospheric Chemistry and Physics, 14, 2, 1104, 1121, 2014, [Peer-reviewed]
    English, Scientific journal
  • Chemicalcompositionofsurfacesnowandice,andprecipitationon QiyiGlacier,QilianMountains,westernChina               
    Takayuki MIYAKE, Jun UETAKE, Sumito MATOBA, Akiko SAKAI, Koji FUJITA, Yoshiyuki FUJII, Tandong YAO, Masayoshi NAKAWO
    Seppyo, 76, 1, 3, 17, Jan. 2014, [Peer-reviewed]
    Japanese, Scientific journal
  • Initial field observations on Qaanaaq ice cap, northwestern Greenland
    Shin Sugiyama, Daiki Sakakibara, Satoshi Matsuno, Satoru Yamaguchi, Sumito Matoba, Teruo Aoki
    ANNALS OF GLACIOLOGY, 55, 66, 25, 33, INT GLACIOL SOC, 2014, [Peer-reviewed]
    English, Scientific journal, To study the glaciological processes controlling the mass budget of Greenland's peripheral glaciers and ice caps, field measurements were carried out on Qaanaaq ice cap, a 20 km long ice cap in northwestern Greenland. In the summer of 2012, we measured surface melt rate, ice flow velocity and ice thickness along a survey route spanning the ice margin (200 m a.s.l.) to the ice-cap summit (1110 m a.s.l.). Melt rates in the ablation area were clearly influenced by dark materials covering the ice surface, where degree-day factors varied from 5.44 mm w.e. K-1 d(-1) on a clean surface to 8.26 mm w.e. K-1 d(-1) in the dark regions. Ice velocity showed diurnal variations, indicating the presence of surface-meltwater induced basal sliding. Mean ice thickness along the survey route was 120 m, with a maximum thickness of 165m. Ice velocity and temperature fields were computed using a thermomechanically coupled numerical glacier model. Modelled ice temperature, obtained by imposing estimated annual mean air temperature as the surface boundary condition, was substantially lower than implied by the observed ice velocity. This result suggests that the ice dynamics and thermodynamics of the ice cap are significantly influenced by heat transfer from meltwater and changing ice geometry.
  • 降雨と融雪が重なって生じる融雪出水(2) —3カ年の模擬降雨散水実験の比較—               
    石井吉之, 中坪俊一, 森章一, 的場澄人
    北海道の雪氷, 32, 29, 32, Jan. 2014
    Japanese, Scientific journal
  • Long-term variation of light-absorbing snow impurities in Sapporo, Japan
    Katsuyuki Kuchiki, Aoki Teruo, Niwano Masashi, Matoba Sumito, Kodama Yuji
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2014, 158, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2014
    Japanese
  • Alpine ice-core drilling in the North Pacific region
    Sumito Matoba, Kunio Shimbori, Takayuki Shiraiwa
    ANNALS OF GLACIOLOGY, 55, 68, 83, 87, INT GLACIOL SOC, 2014, [Peer-reviewed]
    English, Scientific journal, The Institute of Low Temperature Science at Hokkaido University conducted ice-core drilling in alpine glaciers in the northern North Pacific region to reconstruct climate change in this region for the past few hundred years. We drilled two ice cores in the Kamchatka Peninsula, Russia. An ice core with a length of 211 m was drilled on a glacier at the summit caldera of Ushkovsky mountain in 1998. A second core, with a length of 115 m (until bedrock was reached), was drilled on a glacier at the summit caldera of Ichinsky mountain in 2006. We drilled three further ice cores in Alaska, USA. Two ice cores with lengths of 50 and 212 m were drilled on a glacier at the summit caldera of Mount Wrangell in 2003 and 2004. The third ice core was drilled on the ice divide among three glaciers, Black Rapids, Trident and Susitna glaciers, which represent a flat saddle north of Aurora Peak in the Alaska Range. This paper details the field operations and characteristics of the different ice-drilling systems used and the problems encountered.
  • Spatial variations of δ18O and ion species in the snowpack of the northwestern Greenland ice sheet
    Sumito Matoba, Tetsuhide Yamasaki, Morihiro Miyahara, Hideaki Motoyama
    Bulletin of Glaciological Research, 32, 1, 79, 84, Japanese Society of Snow and Ice, 2014, [Peer-reviewed]
    English, Scientific journal, To determine the transport processes of water vapor and aerosols over the northwestern Greenland ice sheet, we undertook a glaciological observation at a coastal site on the northwestern part of the ice sheet and revealed spatial variations in δ18O and in the concentrations of chemical substances in surface snow and the snowpack. On the outlet glacier (the Meehan glacier), water vapor and sea salt were transported from the coast. On the inland ice sheet in northwestern Greenland, water vapor, mineral dust, anthropogenic substances such as NO3- and SO42-, and CH3SO3- from marine phytoplankton were transported from the west coast of Greenland via the central part of the Greenland ice sheet. © Japanese Society of Snow and Ice.
  • Relation between SSA and grain size of snow
    Akihiro Hachikubo, Martin Schneebeli, Satoru Yamaguchi, Masahiro Hori, Tomonori Tanikawa, Konosuke Sugiura, Sumito Matoba, Masashi Niwano, Katsuyuki Kuchiki, Teruo Aoki
    Hokkaido no Seppyo, 33, 33, 121, 124, 公益社団法人日本雪氷学会北海道支部, 2014
    Japanese, Scientific journal
  • Glaciological observations in 2012 and 2013 at SIGMA-A site, Northwest Greenland
    Satoru Yamaguchi, Sumito Matoba, Tetsuhide Yamazaki, Akane Tsushima, Masashi Niwano, Tomonori Tanikawa, Teruo Aoki
    Bulletin of Glaciological Research, 32, 1, 95, 105, Japanese Society of Snow and Ice, 2014, [Peer-reviewed]
    English, Scientific journal, Glaciological observations were conducted in 2012 and 2013 at the SIGMA-A site on the northwest Greenland ice sheet (78° 03'06"N, 67° 37'42"W, 1490 m a.s.l.) as part of the Snow Impurity and Glacial Microbe effects on abrupt warming in the Arctic (SIGMA) project. The meteorological conditions during the two observations were quite different. The meteorological condition during the 2012 observation period was warm, and heavy rainfall occurred during the observation period, thus the snow was very wet. In contrast, the meteorological condition during the observation period in 2013 was cold, with a blowing snow event, thus the snow was quite dry. The glaciological observations in 2012 consisted of 1) snow-stake measurements, 2) snow pit observations, 3) grain size observations for validation of satellite-derived snow products, 4) snow specific surface area measurements using a near-infrared camera, 5) snow sampling for chemical analyses, and 6) drilling of firn cores with a hand auger. The glaciological observations in 2013 consisted of 1) snow-stake measurements, 2) snow pit observations, and 3) snow sampling for chemical analyses. © Japanese Society of Snow and Ice.
  • Effects of temperature and grain type on time variation of snow specific surface area
    Akihiro Hachikubo, Satoru Yamaguchi, Hayato Arakawa, Tomonori Tanikawa, Masahiro Hori, Konosuke Sugiura, Sumito Matoba, Masashi Niwano, Katsuyuki Kuchiki, Teruo Aoki
    Bulletin of Glaciological Research, 32, 1, 47, 53, Japanese Society of Snow and Ice, 2014, [Peer-reviewed]
    English, Scientific journal, The specific surface area (SSA) of snow is of particular interest to researchers because SSA is strongly related to snow albedo and is a comparatively better indicator of snow's complexity than grain size. The time variation of SSA for fresh snow samples was observed in the laboratory under isothermal conditions at 226 K and 254 K using the gas adsorption method and Brunauer-Emmett-Teller theory. The SSA of the snow samples decreased with time under isothermal metamorphism. The decrease in SSA was fitted with the logarithmic equation proposed by Legagneux et al. (2003), and adjustable parameters were obtained. The rate of decrease in SSA depended on the shape of the initial snow type and temperature. Dendritic snow samples exhibited large initial SSAs, and their SSAs decreased faster compared with those of fragmented (collected from drifting snow) and plate-like precipitation particles with relatively small initial SSAs. The rate of decrease in SSA was lower at 226 K than that at 254 K. © Japanese Society of Snow and Ice.
  • Dependence of thermal infrared emissive behaviors of snow cover on the surface snow type
    Masahiro Hori, Teruo Aoki, Tomonori Tanikawa, Katsuyuki Kuchiki, Masashi Niwano, Satoru Yamaguchi, Sumito Matoba
    Bulletin of Glaciological Research, 32, 1, 33, 45, Japanese Society of Snow and Ice, 2014, [Peer-reviewed]
    English, Scientific journal, The potential of the thermal infrared (TIR) remote sensing for discriminating surface snow types was examined by analyzing TIR radiances acquired from space over the Greenland ice sheet. The brightness temperature difference (BTD) between TIR wavelengths of 11 and 12μm was found to increase in accordance with in situ observed evolutions of surface snow type. Spatial and temporal distributions of BTD over the entire ice sheet indicated that BTD has a sensitivity of about 1.2 K for variations of the possible snow types. The observed behaviors of BTD were coincident with those predicted by a radiative transfer calculation using previous in situ measured snow emissivities, although some biases on the order of 0.1-0.3 K remain. The dependence of BTD on the surface snow type was also consistent with the behaviors of snow reflectance at the shortwave infrared (SWIR) wavelength 1.6μm, which is a measure of snow grain size, except for the case of melting wet snow. The inconsistency in the wet snow case was considered to be due to the different optical responses of the TIR and SWIR signals to wet snow, which suggested the possibility of using TIR signals to discriminate wet/dry conditions of snow cover in an old stage. As a result, it is determined that TIR remote sensing has potential not only as an approach supplementary to the SWIR method for assessing surface snow types in daytime but also as the only method for simultaneous retrieval of snow type and surface temperature in nighttime. © Japanese Society of Snow and Ice.
  • Light-absorbing snow impurity concentrations measured on Northwest Greenland ice sheet in 2011 and 2012
    Teruo Aoki, Sumito Matoba, Satoru Yamaguchi, Tomonori Tanikawa, Masashi Niwano, Katsuyuki Kuchiki, Kouji Adachi, Jun Uetake, Hideaki Motoyama, Masahiro Hori
    Bulletin of Glaciological Research, 32, 1, 21, 31, Japanese Society of Snow and Ice, 2014, [Peer-reviewed]
    English, Scientific journal, Light-absorbing snow impurities of elemental carbon (EC), organic carbon (OC), and mineral dust have been measured at three locations at elevations from 1,469 to 1,992 m on August 1, 2011, and at the site SIGMA-A (78oN, 68oW, elevation 1,490 m) on the northwest Greenland ice sheet (GrIS) during the period from June 28 to July 12, 2012. At SIGMA-A, a remarkable snow surface lowering together with snow melting was observed during the observation period in 2012, when a record surface melting event occurred over the GrIS. The concentrations in the surface were 0.9, 3.8, and 107 ppbw for EC, OC, and dust, respectively, at the beginning of the period, which increased to 4.9, 17.2, and 1327 ppbw for EC, OC, and dust, respectively, at the end. The EC and dust concentrations were remarkably higher than those at the three locations in 2011 and the recent measurements at Summit. However, our measurements for EC and OC could be underestimated because a recent study indicates that the collection efficiency of a quartz fiber filter, which we employed, is low. We confirm that the snow surface impurity concentrations were enhanced in the observation period, which can be explained by the effects of sublimation/evaporation and snow melt amplification associated with drastic melting. Scanning electron microscopy analysis of surface snow impurities on July 12 revealed that the major component of snow impurities is mineral dust with size larger than 5 μm, which suggests possible emission source areas are peripheral bare soil regions of Greenland and/or the Canadian Arctic. © Japanese Society of Snow and Ice.
  • Field activities of the "Snow Impurity and Glacial Microbe effects on abrupt warming in the Arctic" (SIGMA) Project in Greenland in 2011-2013
    Teruo Aoki, Sumito Matoba, Jun Uetake, Nozomu Takeuchi, Hideaki Motoyama
    Bulletin of Glaciological Research, 32, 1, 3, 20, Japanese Society of Snow and Ice, 2014, [Peer-reviewed]
    English, Scientific journal, Field activities of the "Snow Impurity and Glacial Microbe effects on abrupt warming in the Arctic" (SIGMA) Project in Greenland in the summer season of 2011-2013 are reported
    this consists of (1) glaciological and meteorological observations and (2) biological observations. In 2011, we conducted a field reconnaissance in the Qaanaaq, Ilulissat and Kangerlussuaq areas to enable continuous meteorological observations with automatic weather stations (AWS), campaign observations for glaciology, meteorology and Biology and shallow ice core drilling, which were planned for 2012-2014. Based on the results, we chose the Qaanaaq area in northwest Greenland as our main activity area and the Kangerlussuaq area in mid-west Greenland partly for biological observations. In 2012, we conducted field observations for (1) and (2) mentioned above together with installations of two AWSs at site SIGMA-A on The Greenland ice sheet (GrIS) and at site SIGMA-B on the Qaanaaq ice cap (QIC) from June to August. Surface snow and ice over all of the QIC melted in July and August 2012, and most of the Glacier surface appeared to be dark-colored, probably due to mineral dust and glacial microbial products. In 2013, we carried out similar observations in the Qaanaaq area. However, the weather and Glacier surface conditions were considerably different from those in 2012. Snow cover over the summer of 2013 remained over large areas with elevations higher than about 700 m on QIC. Biological activity on the Glacier surface appears to be substantially lower as compared to that in 2012. © Japanese Society of Snow and Ice.
  • 降雨と融雪が重なって生じる融雪出水 —3カ年の模擬降雨散水実験の比較—               
    石井吉之, 中坪俊一, 森章一, 的場澄人
    北海道の雪氷, 31, 104, 107, Sep. 2012
    Japanese, Scientific journal
  • Study of precise measurement for borehole temperature in glacier and ice sheet
    Motoyama Hideaki, Furusaki Atsushi, Takahashi Hiromu, Takata Morimasa, Takahashi Akiyoshi, Miyahara Morihiro, Motoba Sumito, Sugiyama Shin, Iizuka Yoshinori, Shinbori Kunio
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2012, 161, 161, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, 2012
    Japanese
  • Glacier flow measurement and radio-echo sounding at Aurora Peak, Alaska, in 2008
    Takehiro Fukuda, Shin Sugiyama, Sumito Matoba, Takayuki Shiraiwa
    ANNALS OF GLACIOLOGY, 52, 58, 138, 142, INT GLACIOL SOC, 2011, [Peer-reviewed]
    English, Scientific journal, As part of a deep ice-core drilling project, GPS and ice-radar measurements were made in the vicinity of Aurora Peak, Alaska, USA. Surface and bed elevation maps were obtained over an area of 400 m x 700 m, which includes the drilling site. Surface flow velocity was measured at 18 locations in the same area. The results showed that the drilling site was situated on a gentle north-south ridge with saddle-shaped surface geometry. The horizontal ice-flow velocity at the drilling site was <0.5 m a(-1) and the ice generally flowed eastward and westward along the surface slope. The glacier bed slopes to the east and has more complex topography than the ice surface. The drilling site was situated above a bedrock dip, with an ice thickness of 252 +/- 10 m. These data constitute important information for estimating the effect of ice flow to the ice core retrieved from the depth of up to 180.17 m.
  • Records of sea-ice extent and air temperature at the Sea of Okhotsk from an ice core of Mount Ichinsky, Kamchatka
    Sumito Matoba, Takayuki Shiraiwa, Akane Tsushima, Hirotaka Sasaki, Yaroslav D. Muravyev
    ANNALS OF GLACIOLOGY, 52, 58, 44, 50, CAMBRIDGE UNIV PRESS, 2011, [Peer-reviewed]
    English, Scientific journal, The Sea of Okhotsk is the southernmost area in the Northern Hemisphere where seasonal sea ice is produced every year. The formation of sea ice drives thermohaline circulation in the Sea of Okhotsk, and this circulation supports the high productivity in the region. However, recent reports have indicated that sea-ice production in the Sea of Okhotsk is decreasing, raising concern that the decreased sea ice will affect not only circulation but also biological productivity in the sea. To reconstruct climatic changes in the Sea of Okhotsk region, we analyzed an ice core obtained from Ichinskaya Sopka (Mount Ichinsky), Kamchatka. We assumed that the remarkable negative peaks of delta D in the ice core were caused by expansion of sea ice in the Sea of Okhotsk. Melt feature percentage (MFP), which indicates summer snowmelt, showed high values in the 1950-60s and the mid-1990s-2000s. The high MFP in the 1950-60s was assumed to be caused by an increase in cyclone activity reaching Kamchatka during a negative period of the Pacific Decadal Oscillation index, and that in the 1990-2000s may reflect the increase in solar irradiation during a positive period of the summer Arctic Oscillation index.
  • Temporal and Spatial Variations of Wet Deposition Flux of Mineral Dust in Japan
    Osada, K., Ura, S., Kagawa, M., Mikami, M., Tanaka, T. Y., Matoba, S., Aoki, K., Shinoda, M., Kurosaki, Y., Hayashi, M., Shimizu, A., Uematsu, M.
    Sola, 7, 49, 52, 2011, [Peer-reviewed]
    English, Scientific journal
  • Estimation of Mineral Dust Amount Using Fe Content in Water-Insoluble Residue of Atmospheric Deposition Samples
    Ura, Sachiho, Osada, Kazuo, Kagawa, Masako, Mikami, Masao, Matoba, Sumito, Aoki, Kazuma, Shinoda, Masato, Kurosaki, Yasunori, Hayashi, Masahiko, Shimizu, Atsushi, Uematsu, Mitsuo
    Earozoru Kenkyu, 26, 3, 234, 241, 2011, [Peer-reviewed]
    Japanese, Scientific journal
  • Nutrient distributions associated with snow and sediment-laden layers in sea ice of the southern Sea of Okhotsk
    Daiki Nomura, Jun Nishioka, Mats A. Granskog, Andreas Krell, Sumito Matoba, Takenobu Toyota, Hiroshi Hattori, Kunio Shirasawa
    MARINE CHEMISTRY, 119, 1-4, 1, 8, ELSEVIER SCIENCE BV, Apr. 2010, [Peer-reviewed]
    English, Scientific journal, Samples of first-year sea ice, snow and under-ice water were collected in the southern Sea of Okhotsk in mid-February 2007 and 2008 to elucidate the processes controlling nutrient concentrations in sea ice. Temperature, salinity, oxygen isotopic ratio (delta O-18) and inorganic nutrient concentrations (NO3, NH4, NO2, PO4 and SiO2) were measured. Sea ice was categorized into four types; snow-ice, frazil ice, columnar ice and a mixture of granular and columnar ice, based on delta O-18 composition and ice texture. Frazil ice dominated the total ice thickness (52.8%), and columnar ice was sandwiched between frazil ice layers, indicating dynamic ice-growth processes such as rafting and ridging. Furthermore, the ice was banded by layers of particulate materials (sediment layers), which were frequently encountered during cruises. High NO3 and NH4 concentrations were found in snow and snow-ice implying that these were supplied from the atmosphere with snowfall and incorporated into the sea ice through snow-ice formation. In the sediment-laden layers, which were categorized as frazil ice, NO2, PO4 and SiO2 concentrations were highest of all the ice types and considerably enriched compared to parent seawater, suggesting the remineralization of the particulate organic matter. On the other hand, NO3 concentrations in sediment layers were low (depleted), leading to extremely low N (NO3 + NH4 + NO2): P ratios in sediment layers, from 0.2 to 0.8, with respect to that of under-ice water or Redfield ratio. These results suggest that in part of sediment-laden layers fixed-nitrogen was removed partially as molecular nitrogen (N-2) from the sea ice environment by anaerobic nitrate reduction processes (denitrification) by denitrifying bacteria while adding phosphate from associated remineralization of organic phosphorus. The effect of melting of snow and sea ice is dilution for salinity, NO3 and SiO2, no change in NO2 and PO4, and a minor enrichment for NH4 in the mixed layer in spring and early summer. This suggests that snow/ice meltwater with different nutrient ratios than in under-ice water/Redfield ratio is supplied to under-ice water during melt season in April/May in southern Sea of Okhotsk. However, the impact of sediment-laden sea ice cannot be assessed at this point. (C) 2009 Elsevier B.V. All rights reserved.
  • A snow algal community on the surface and ice an ice core of Rikha-Samba Glacier in Western Nepalii Himalayas               
    Takeuchi, N, K. Fujita, F. Nakazawa, S. Matoba, M. Nakawo, B. Rana
    Bulletin of Glaciological Research, 27, 25, 35, 2009, [Peer-reviewed]
    English, Scientific journal
  • Constituent elements of insoluble and non-volatile particles during the Last Glacial Maximum exhibited in the Dome Fuji (Antarctica) ice core
    Yoshinori Iizuka, Takayuki Miyake, Motohiro Hirabayashi, Toshitaka Suzuki, Sumito Matoba, Hideaki Motoyama, Yoshiyuki Fujii, Takeo Hondoh
    JOURNAL OF GLACIOLOGY, 55, 191, 552, 562, CAMBRIDGE UNIV PRESS, 2009, [Peer-reviewed]
    English, Scientific journal, In order to find environmental signals based on the dust and calcium-ion concentrations in ice cores, we determine the constituent elements of residue particles obtained after melting ice samples. We have designed a sublimating system that operates at -45 degrees C, below the eutectic temperatures of major salts. This system permits us to obtain a great many non-volatile particles. After studying the nonvolatile particles, we immersed them in water to remove soluble particles and compounds. We thereby analyzed a total of 1272 residue particles (from the melted sample), 2418 non-volatile particles (after sublimation) and 1463 insoluble particles taken from five sections of Last Glacial Maximum ice from the Dome Fuji (Antarctica) ice core. Their constituent elements were determined by scanning electron microscopy/energy-dispersive X-ray spectrometry (SEM-EDS) and compared to the dust, calcium-ion and sodium-ion concentrations measured by ion chromatography. Our results indicate that >99.9% of the insoluble particles contain silicon but no sulfur, nitrogen or chlorine. A significant number of the non-volatile particles, however, contain sulfur and chlorine. We conclude that insoluble dust consists mostly of silicate, that almost all calcium ions originate from calcium sulfate and that almost all sodium ions originate from sodium sulfate and sodium chloride.
  • Seasonality of snow accumulation at Mount Wrangell, Alaska, USA
    Syosaku Kanamori, Carl S. Benson, Martin Truffer, Sumito Matoba, Daniel J. Solie, Takayuki Shiraiwa
    JOURNAL OF GLACIOLOGY, 54, 185, 273, 278, INT GLACIOL SOC, 2008, [Peer-reviewed]
    English, Scientific journal, We recorded the burial times of temperature sensors mounted on a specially constructed tower to determine snow accumulation during individual storms in the summit caldera of Mount Wrangell, Alaska, USA, (62 degrees N, 144 degrees W; 4100 m a.s.l.) during the accumulation year June 2005 to June 2006. The experiment showed most of the accumulation occurred in episodic large storms, and half of the total accumulation was delivered in late summer. The timing of individual events correlated well with storms recorded upwind, at Cordova, the closest Pacific coastal weather station (200 km south-southeast), although the magnitude of events showed only poor correlation. Hence, snow accumulation at Mount Wrangell appears to be a reflection of synoptic-scale regional weather systems. The accumulation at Mount Wrangell's summit (>2.5 m w.e.) exceeded the precipitation at Cordova. Although the direct relationship between accumulation of individual storms at the summit of Mount Wrangell and precipitation events at Cordova may be unique in the region, it is useful for interpreting ice cores obtained on Mount Wrangell. This is especially the case here because the high rate of accumulation allows high time resolution within the core.
  • Glacier mass balance interpreted from biological analysis of firn cores in the Chilean lake district
    P. Santibanez, S. Kohshima, R. Scheihing, J. Jaramillo, T. Shiraiwa, S. Matoba, D. Kanda, P. Labarca, G. Casassa
    JOURNAL OF GLACIOLOGY, 54, 186, 452, 462, INT GLACIOL SOC, 2008, [Peer-reviewed]
    English, Scientific journal, The first analyses of biological components in glaciers of the Chilean lake district are presented based on microalgae biovolume, pollen and other microorganisms detected in shallow (similar to 10m) firn/ice cores. Three cores were retrieved, two at Volcan Mocho-Choshuenco (39 degrees 55' S, 72 degrees 02' W; summit at 2422 m a.s.l; east glacier at 2000 m a.s.l.), and one at the summit of Volcan Osorno (41 degrees 06' S, 72 degrees 30' W; 2652 m a.s.l.). Microalgae, protozoa and pollen quantified in the samples obtained from the two summit cores show clear fluctuations interpreted as seasonal signs. In contrast, delta D and many chemical species from the summit cores show strong dampening at depth, probably due to water percolation. The limited information provided by isotopic and chemical analyses is used to support the seasonal interpretation of biological parameters from the summit cores, with microorganism maxima inferred to occur in summer and pollen maxima in spring. A good comparison is found between mass-balance estimations from the Volcan Mocho-Choshuenco summit core and values obtained near that site by means of the stake method. it is concluded that biological analyses of firn/ice cores provide reliable estimations of annual and seasonal markers from these temperate glaciers.
  • Estimation of net accumulation rate at a Patagonian glacier by ice core analyses using snow algae
    Shiro Kohshima, Nozomu Takeuchi, Jun Uetake, Takayuki Shiraiwa, Ryu Uemura, Naohiro Yoshida, Sumito Matoba, Maria Angelica Godoi
    GLOBAL AND PLANETARY CHANGE, 59, 1-4, 236, 244, ELSEVIER SCIENCE BV, Oct. 2007, [Peer-reviewed]
    English, Scientific journal, Snow algae in a 45-97-m-long ice core from the Tyndall Glacier (50 degrees 59'05 '' S, 73 degrees 31'12 '' W, 1756 m a.s.l.) in the Southern Patagonian Icefield were examined for potential use in ice core dating and estimation of the net accumulation rate. The core was subjected to visual stratigraphic observation and bulk density measurements in the field, and later to analyses of snow algal biomass, water isotopes (180, D), and major dissolved ions. The ice core contained many algal cells that belonged to two species of snow algae growing in the snow near the surface: Chloromonas sp. and an unknown green algal species. Algal biomass and major dissolved ions (Na(+), K(+), Mg(2+) Ca(2+), Cl(-), SO(4)(2-)) exhibited rapid decreases in the upper 3 m, probably owing to melt water elution and/or decomposition of algal cells. However, seasonal cycles were still found for the snow algal biomass, (18)O, D-excess, and major ions, although the amplitudes of the cycles decreased with depth. Supposing that the layers with almost no snow algae were the winter layers without the melt water essential to algal growth, we estimated that the net accumulation rate at this location was 12.9 m a(-1) from winter 1998 to winter 1999, and 5.1 m from the beginning of winter to December 1999. These estimates are similar to the values estimated from the peaks of 180 (17.8 m a(-1) from summer 1998 to summer 1999 and 11.0 m from summer to December 1999) and those of D-excess (14.7 m a(-1) from fall 1998 to fall 1999 and 8.6 m a(-1) from fall to December 1999). These values are much higher than those obtained by past ice core studies in Patagonia, but are of the same order of magnitude as those predicted from various observations at ablation areas of Patagonian glaciers. (C) 2006 Elsevier B.V. All rights reserved.
  • Interpretation of detailed density profile on Mt. Wrangell, Alaska
    KANAMORI Syosaku, SHIRAIWA Takayuki, MATOBA Sumito, YASUNARI Teppei
    Preprints of the Annual Conference, Japanese Society of Snow and Ice, 2007, 2, 2, THE JAPANESE SOCIETY OF SNOW AND ICE, 2007
    Japanese
  • The fluctuation of iron concentration in an ice core of Mt. Wrangell, Alaska
    Sasaki Hirotaka, Matoba Sumito, Shiraiwa Takayuki
    Preprints of the Annual Conference, Japanese Society of Snow and Ice, 2007, 126, 126, THE JAPANESE SOCIETY OF SNOW AND ICE, 2007
    Japanese
  • The glaciological expedition to Mount Ichinsky, Kamchatka, Russia
    Matoba, S, S. V. Ushakov, K. Shimbori, H. Sasaki, T. Yamasaki, A. A. Ovshannikov, A. G. Manevich, T. M. Zhideleeva, S. Kutuzov, Y. D. Muravyev, T. Shiraiwa
    Bulletin of Glaciological Research, 24, 79, 85, Japanese Society of Snow and Ice, 2007, [Peer-reviewed]
    English, During summer 2006, we carried out ice-core drilling to bedrock on a glacier at the summit of Mount Ichinsky, Kamchatka, Russia, and recovered a 115-m-long ice core. We also prepared samples, performed ice-core analyses in-situ, and measured the borehole temperature. The temperature of the borehole was -13℃ at 10m depth, and the pore close-off depth was 25m. The melt-feature percentage, or the thickness of frozen ice layers in a 1-m-long section of ice core, varied from 10% to 100%. These ice layers were formed by both rainfall, surface melting, and frost on the glacier surface, which we observed during our expedition. We hypothesize that the fluctuations in the proportion of ice layers show climatic variation in Kamchatka.
  • Stable isotope records recovered from ice cores in Mt.Wrangell , Alaska
    Toida Takeshi, Shiraiwa Takayuki, Matoba Sumito
    Preprints of the Annual Conference, Japanese Society of Snow and Ice, 2006, 170, 170, THE JAPANESE SOCIETY OF SNOW AND ICE, 2006
    Japanese
  • Chemical composition of surface ice at July 1st Glacier, Qilian Mountains, China
    Miyake Takayuki, Uetake Jun, Matoba Sumito, Sakai Akiko, Fujita Koji, Fujii Yoshiyuki, Yao Tandong, Nakawo Masayoshi
    Preprints of the Annual Conference, Japanese Society of Snow and Ice, 2006, 202, 202, THE JAPANESE SOCIETY OF SNOW AND ICE, 2006
    Japanese
  • Meteorological observation at July 1st Glacier in northwest China from 2002 to 2005
    A. Sakai, Y. Matsuda, K. Fujita, S. Matoba, J. Uetake, K. Satow, K. Duan, J. Pu, M. Nakawo, T. YAO
    Bulletin of Glaciological Research, 23, 23, 32, 2006, [Peer-reviewed]
    English
  • Preliminary observations of sub-surface and shallow ice core at July 1st Glacier, China in 2002-2004
    J. Uetake, A. Sakai, Y. Matsuda, K. Fujita, H. Narita, S. Matoba, K. Duan, M. Nakawo, T. Yao
    Bulletin of Glaciological Research, 23, 85, 93, 2006, [Peer-reviewed]
    English
  • New Method of Detecting Kosa (Asian Dust) from SPM Data Measured by Environmental Air Monitoring Stations
    MATOBA Sumito, MORI Ikuko, HAYAKARI Susumu, NISHIKAWA Masataka
    Earozoru Kenkyu, 20, 3, 225, 230, Japan Association of Aerosol Science and Technology, 2005, [Peer-reviewed]
    English, We developed a new method for detecting Kosa (Asian dust) days from the suspended particulate matter (SPM) concentrations measured at seven air-quality monitoring stations in western Japan. When the frequency curve of the horary SPM concentration monitored at each station from January to May showed a bimodal distribution, we assigned a threshold value to extract the distribution of higher concentration. When the days with high SPM concentration were in agreement over a wide area, we defined them as SPM Kosa days. There were 101 SPM Kosa days from 1993 to 2001. Through the analysis of the distribution of atmospheric pressure and the back trajectory analysis, we confirmed that the present method was able to detect 100 Kosa days out of 101, including the Kosa days which were not detected visually because of its weak event. There were 20 SPM Kosa days in 1999, which was the maximum number of Kosa days observed during 1993-2001.
  • Scientific prospect of a certified reference material for study on the urban dust in China               
    Sun, Z, M. Nishikawa, Z. Wu, I. Mori, S. Matoba
    Proceedings of China-Japan Joint Symposium on Environmental Chemistry, 170, 172, 2004, [Peer-reviewed]
    English, International conference proceedings
  • Comparison of atmospheric particulate pretreatment method for ICP-AES anaysis               
    Mori, I, Matoba, S, Sano, T, Di, Y, Quan, H, Nishikawa, M
    Proceedings of China-Japan Joint Symposium on Environmental Chemistry, 207, 208, 2004, [Peer-reviewed]
    English, International conference proceedings
  • Chemical characteristics in a 22-m ice core on the Belukha Glacier, Russia
    Y. Iizuka, K. Fujita, S. Matoba, Y. Fujii, K. Matsuki, M. Kohno, V.B. Aizen
    Polar Meteorology and Glaciology, 18, 114, 120, National Institute of Polar Research, 2004, [Peer-reviewed]
    English, To better understand how the chemical composition of a glacier in an inland continental region relates to the local climate, we collected ice core samples from the Belukha Glacier, Russia, in July 2001. We analyzed the samples for pH, anions, and cations. The primary soluble ions were SO42-, NO3-, NH4+, Ca2+, and HCOO-. Moreover, we argue the following. 1) Ca2+ and its equivalent SO42-+ NO3- likely originated from terrestrial dust such as soil. 2) HCOO- and its equivalent NH4+ likely originated from vegetation and/or biomass burning. 3) The remaining SO42-+NO3- and NH4+ likely originated from livestock, commercial fertilizers, and natural fertilizers. 4) The NH4+ concentration was low when there was no contribution from vegetation and/or biomass burning.
  • Parallel testing of continuous monitoring equipment for PM2.5 and annual variation in PM2.5/SPM ratio               
    Matoba, S, Mori, I, Hasegawa, S, Tanabe, K, Nishikawa, M
    Proceedings of China-Japan Joint Symposium on Environmental Chemistry, 310, 311, 2004
  • Report on the cross-checks on snow samplings and chemical analyses carried out in the "Yuki-Gasshuku (Snow Camp) 2002" held by the Subcommittee on Snow and Ice Chemistry
    MATOBA Sumito
    Journal of the Japanese Association of Snow and Ice, 65, 3, 317, 321, The Japanese Society of Snow and Ice, 15 May 2003
    Japanese, 2002年1月16日に北海道雨竜郡幌加内町字母子里にある北海道大学低温科学研究所融雪観測室・露場にて行われた「雪合宿」において,化学分析のための積雪採取方法とイオンクロマトグラフィによる積雪中の化学主成分の定量方法のクロスチェックが行われた.6方法での試料採取・処理を行った.その結果,積雪から試料瓶に直接採取する方法では深さ方向に均一にサンプリングできず,結果が他と異なることが分かった.その他の方法には大きな問題が見つからなかった.化学主成分の定量は,5機関にて行われた.K+は積雪中の濃度が低く,かつ定量限界が高いため分析値にばらつきが見られた.他の成分については,特徴的な測定値のばらつきが見られた研究機関もあったが,大きな問題は見つからなかった.
  • A 320 k-year record of microparticles in the Dome Fuji, Antarctica ice core measured by laser-light scattering
    Y. Fujii, M. Kohno, S. Matoba, H. Motoyama, O. Watanabe
    Mum. Natl. Inst. Polar Res. Spec. Issue, "Global Scale Climate and Environment Study through Polar Deep Ice Cores", 57, 46, 62, 2003, [Peer-reviewed]
    English, Research institution, A laser-light scattering method was evaluated from the viewpoint of the measurement ability of concentration and size distribution of microparticles in molten ice core samples. It was demonstrated that analysis can be performed with 10 % accuracy by diluting the sample with ultrapure water by 50 times to eliminate coincidence loss. Using this method, the concentration and size distribution of microparticles were determined on 2829 samples from a 2503 m deep ice core drilled at Dome Fuji, Antarctica. The present paper shows the profiles of number and volume concentrations through the whole depth and the changes in the size distribution through three glacial cycles in the past 320 k-years.
  • An overview of the Japanese glaciological studies on Mt. Logan, Yukon Territory, Canada in 2002
    K. Goto-Azuma. T, Shiraiwa, S. Matoba, T Segawa, S. Kanamori, Y, Fujii, T. Yamasaki
    Bulletin of Glaciological Research, 20, 65, 72, 2003, [Peer-reviewed]
    English, Scientific journal
  • Ice core drilling at King Col, Mount Logan 2002
    T. Shiraiwa, K. Goto-Azuma, S. Matoba, T. Yamasaki, T. Segawa, S. Kanamori, K. Matsuoka, Y. Fujii
    Bulletin of Glaciological Research, 20, 57, 63, 2003, [Peer-reviewed]
    English, Scientific journal
  • Anthropogenic trace metals in an ice core at Vestfonna, Svalbard, Norway               
    S. Matoba, H. Narita, H. Motoyama, O. Watanabe
    Chinese Journal of Polar Science, 14, 1, 41, 47, 2003, [Peer-reviewed]
    English
  • Ice core chemistry of Vestfonna Ice Cap in Svalbard, Norway
    S Matoba, H Narita, H Motoyama, K Kamiyama, O Watanabe
    JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 107, D23, doi:10.1029/2002JD002205, AMER GEOPHYSICAL UNION, Dec. 2002, [Peer-reviewed]
    English, Scientific journal, [1] Chemical analyses were done on samples from a 2.2-m deep snow pit and a 211-m deep ice core that came from the top of the Vestfonna Ice Cap in Nordaustlandet, Svalbard, Norway. The snow pit samples showed that the temperature increased during the winter owing to advection of warm air from the south, and delta(18)O did not show a seasonal cycle. Chronology of the ice core was determined by tritium analysis and comparison to the signal from the volcanic eruption of Laki; the resulting accumulation rate was 0.34-0.35 m water eq. yr(-1) for the last 400 years. The delta(18)O profile in the ice core revealed a warm period from 1920 up to the present in Svalbard. According to nonseasalt (nss) SO42- and NO3- concentrations, anthropogenic substances had increased from 1940s but declined from 1970s to the present. The variation of nss SO42- and the increase of NO3- can be explained by an increase of SO2 and NOx emissions from Eurasia. The decline of NO3- is assumed to be caused either by a change in the transport process or by a change of NOx emissions from Europe.
  • Experimental results on improved JARE deep ice core drill - Experiments in Rikubetsu, Hokkaido in 2002               
    Takao Kameda, Yoshiyuki Fujii, Akiyoshi Takahashi, Yoichi Tanaka, Hideki Narita, Kunio Shinbori, Nobuhiko Azuma, Teruo Furukawa, Takayasu Yoshimoto, Morihiro Miyahara, Makoto Igarashi, Mika Kohno, Sumito Matoba, Yoko Toyama, Kazuhide Satow, Shuhei Takahashi, Okitsugu Watanabe
    Antarctic Record, 46, 2, 377, 398, Jul. 2002
    English, Scientific journal, Deep ice coring to bedrock (3028 m in depth) at Dome Fuji Station is planned during three successive summer seasons starting from 2003/2004. An improved JARE deep ice core drill (12.2 m in length and 3.8 m in maximum core length) was developed in December 2001 for the ice coring at Dome Fuji. In January/ February of 2002, we performed experiments on drill performance using artificial ice blocks in Rikubetsu, Hokkaido. In this paper, we outline the experiment and report the results. It was found through the experiment that an ice core of 3.8 m length was smoothly obtained by the improved drill with three screws in the chip chamber and cutting pitch of 5 mm/cycle. About 45000 small holes 1.2 mm in diameter were made on the surface of the chip chamber. These small holes enabled liquid to circulate between cutters and outside of the drill through the chip chamber in the drill. The dry density of the chips was 440 to 500 kg/m3 and the chip recovery rate during ice coring was 65 to 91%. A check valve installed at the bottom of the chip chamber to prevent outflow of chips from the drill was not tested enough, but more durability is needed for the valve. The newly developed motor system and core catchers of the drill worked perfectly. The average coring speed was 24.5 cm/min with cutting pitch of 5 mm/ cycle. The average power consumption during ice coring was 171 W.
  • High net accumulation rates at Campo de Hielo Patagónico Sur, South America, revealed by analysis of a 45.97 m long ice core               
    T, Shiraiwa, S. Kohshima, R. Uemura, N. Yoshida, S. Matoba, J. Uetake, M.A. Godoi
    Annals of Glaciology, 19, 25, 31, 2002, [Peer-reviewed]
    English, Scientific journal
  • Linear and non-linear relations between the high-frequency-limit conductivity, AC-ECM signals and ECM signals of Dome F Antarctic ice core from a laboratory experiment
    S Fujita, N Azuma, H Motoyama, T Kameda, H Narita, S Matoba, M Igarashi, M Kohno, Y Fujii, O Watanabe
    ANNALS OF GLACIOLOGY, VOL 35, 35, 321, 328, INT GLACIOLOGICAL SOC, 2002, [Peer-reviewed]
    English, Scientific journal, Laboratory experiments were done to better understand the electrical conduction mechanisms of impure, polycrystalline ice as represented by the 2503 in Dome Fuji (Antarctica) ice core. Also, two electrical measurement techniques for ice cores were 9 compared and their usefulness for determining the acidity of ice cores was studied. We measured the electrical conductivity and complex permittivity of 167 slab-ice samples at frequencies from 20 Hz to I MHz. Measurements were performed at -21degreesC for all samples, and at -110degrees to -20degreesC for several samples, to examine the effects of temperature. We found linear relations between the AC loss factor and the molarity of sulfuric acid, and between the high-frequency-limit conductivity and the AC loss factor. Thus, the acidity levels can be determined from the AC loss factor. In contrast, the electrical conductivity measurement (ECM) current correlated weakly with the other parameters; furthermore, the correlation worsens at larger signal. In several samples containing high acidity, the dielectric properties had distinct changes near -81 degreesC. We argue that these changes were caused by a change from a liquid-vein-mediated conduction mechanism above the eutectic point of the solute/water/ice system to a solid-phase conduction mechanism at lower temperatures.
  • tudies on climatic and environmental changes during the last few hundred years using ice cores from various sites in Nordaustlandet, Svalbard               
    O. Watanabe, H. Motoyama, M. Igarashi, K. Kamiyama, S. Matoba, K. Goto-Azuma, H. Narita, T. Kameda
    Memoirs of national Institute of Polar Researc h Special Issue, "Environmental Research in the Arctic 2000", 227, 242, 2002, [Peer-reviewed]
    English, Research institution
  • Meteorological observation and chemical compositions of precipitation during the winter and spring season in 1997/98 at Siorapaluk, northwestern Greenland               
    S. Matoba, T. Yamasaki, H. Motoyama
    Bulletin of Glaciological Research, 19, 25, 31, 2002, [Peer-reviewed]
    English
  • Regional characteristics of chemical constituents in surface snow, Arctic cryosphere
    H. Motoyama, O. Watanabe, K. Kamiyama, M. Igarashi, K. Goto-Azuma, Y. Fujii, Y. Iizuka, S. Matoba, H. Narita, T. Kameda
    Polar Meteorol. and Glaciol., 15, 55, 66, National Institute of Polar Research, 2001, [Peer-reviewed]
    English, Scientific journal, Surface snow observations were carried out on many glaciers in the Arctic. The observational sites were in Svalbard, Severnaya Zemlya, Greenland and arctic Canada. The seasonal variations of chemical constituents in snowfall remained in the surface snow on the central Greenland ice sheet where the effect of snowmelt was weak. Conversely, the chemical constituents in the snow layer changed with infiltration of melt water on the Svalbard glacier where strong snowmelt occurred, even in high latitudes. But in general, specific regional characteristics remained in all the glaciers. The concentrations of ions in snow were significantly decreased, because of percolation of melt water. But the ratio of NO_3 to Cl still had unique regional characteristic values.
  • Tephra layers in the Dome Fuji (Antarctica) deep ice core
    Y Fujii, M Kohno, H Motoyama, S Matoba, O Watanabe, S Fujita, N Azuma, T Kikuchi, T Fukuoka, T Suzuki
    ANNALS OF GLACIOLOGY, VOL 29, 1999, 29, 126, 130, INT GLACIOLOGICAL SOC, 1999, [Peer-reviewed]
    English, Scientific journal, A deep ice core drilled to 2503 m depth at Dome Fuji, Antarctica, contains 25 visible tephra layers during the past 340 ka. The thickness of tephra layers is in the range 1-24 mm. The thickness and duration at deposition, determined by a simple ice-flow model, suggests that a violent volcanic eruption caused ash to fall onto the Antarctic ice sheet for similar to 5 years and to form a similar to 100 mm thick tephra layer at 117 ka sp. Two tephra layers at depths of 573 and 2202 m probably originated from volcanoes in the South Sandwich Islands, Southern Ocean, given the size of tephra shards, >20 mu m in diameter, and their major chemical composition. Only eight of the 25 tephra layers call also be recognized in the Vostok (Antarctica) ice core, but all correspond to the Vostok tephras if we consider cloudy bands to be volcanic.
  • Basic analyses of Dome Fuji deep ice core Part1: Stable oxygen and hydrogen isotope ratios, major chemical compositions and dust concentration
    O. Watanabe, Y. Fujii, K. Kamiyama, H. Motoyama, T. Furukawa, M. Igarashi, M. Kohno, S. Kanamori, N. Kanamori, Y. Ageta, M. Nakawo, H. Tanaka, K. Satow, H. Shoji, K. Kawamura, S. Matoba, W. Shimada
    Polar Meteorology and Glaciology, 13, 83, 89, National Institute of Polar Research, 1999, [Peer-reviewed]
    English, Scientific journal, Basic chemical analyses of a 2503m deep ice core obtained at Dome Fuji Station, Antarctica in 1995-1996 were carried out to determine stable oxygen and hydrogen isotope ratios, major chemical compositions and microparticle concentrations. We here describe the analytical procedure and the results as well as the determination of working time scale. The ice core covers the past 340ka which includes three glacial-interglacial cycles clearly shown by the stable oxygen isotope profile. Major chemical compositions and microparticle concentrations larger than 0.52μm show high concentrations in glacials and low in interglacials.
  • 氷コア中の微量金属元素の定量法の開発と金属元素から見たスバールバルの環境変動               
    的場 澄人
    1998
    Japanese, Others
  • Determination of trace elements in an arcitc ice core by ICP/MS with a desolvated micro-concentric nebulizer
    S. Matoba, M. Nishikawa, O. Watanabe, Y. Fujii
    Journal of Environmental Chemistry, 8, 3, 421, 427, Japan Society for Environmental Chemistry, 1998, [Peer-reviewed]
    English, Concentrations of trace elements in an ice core obtained in the polar region have been determined by inductively coupled plasma mass spectrometry (ICP-MS) . For trace metals in the ice core, sample uptake and high sensitivity for analysis are also important due to the limited volume of sample and the low concentrations of analytes. A desolvated micro-concentric nebulizer (MCN-6000), which is a recent development and offers high nebulizer efficiency at low sample consumption volume, in combination with ICP-MS, permitted multi-element determination of ppt levels of Al, V, Cr, Fe, Cu, Zn, As, Ag, Cd, Pb and U within a 2ml sample from a ice core obtained from the Vestfonna ice cap (89° 58' N, 21° 02' E) in Nordaustlandet, Svalbard. The contamination on the ice core exterior was removed with a stepwise melting process. The concentrations of Al, Fe, Cu, Zn and Pb were determined from the results of this analysis.
  • Preliminary report on analysis of melted Dome Fuji ice core obtained in 1993
    O. Watanabe, K. Kamiyama, H. Motoyama, M. Igarashi, S. Matoba, T. Shiraiwa, T. Yamada, H. Shoji, S. Kanamori, N. Kanamori, M. Nakawo, Y. Ageta, S. Koga, K. Satow
    Proc. of the NIPR Symp. Polar Meteorol. and Glaciol., 11, 14, 23, National Institute of Polar Research, 1997, [Peer-reviewed]
    English, International conference proceedings, An ice core from the glacier surface down to 112.59m depth was obtained in 1993 at Dome Fuji Station. The ice core was divided vertically in the home cold laboratory and various analyses were carried out for the solid and liquid phases of core samples. The measurements of numbers of microparticles, electrical conductivity, pH, oxygen isotopic ratio and chemical constituents were carried out for the melted ice core samples. In this report, the procedures and the methods for the measurements are introduced with results obtained. The results open preliminary step on ice core research at Dome Fuji Station, which should be useful to evaluate the environments at the dome in the comparison with core analyses at various sites. The vertical distributions for the some of the values obtained are presented to facilitate further discussion of the past climate and environments.
  • Characteristics of AC-ECM signals obtained by use of the Vestfonna ice core, Svalbard
    K. Matsuoka, H. Narita, K. Sugiyama, S. Matoba, H. Motoyama, O. Watanabe
    Proc. of the NIPR Symp. Polar Meteorol. and Glaciol, 11, 67, 75, National Institute of Polar Research, 1997, [Peer-reviewed]
    English, International conference proceedings, AC-ECM measurements of the Vestfonna ice core were carried out under the following conditions : at -12,-17,-22 and -27℃ under 1MHz; at -22℃ under frequencies from 300kHz to 1MHz. The relationship between conductance measured with AC-ECM and acidity was linear. It is considered that salt impurities also affect to the AC-ECM signals. However, we focus on the effect of acidity, because it is known that the effect of acid on the a. c. conductance is 3.6 times as large as that of salt from DEP analysis of the Dolleman ice core. The intercept of the linear regression is coincident with the conductance of pure ice; at -23℃, it is 3.6nS. The gradient, conductance increases raised acid, is 0.70nS l/μmol at -23℃. The gradients at four temperatures were well fitted with the Arrhenius equation and activation energy is 24.8kJ/mol. Activation energy obtained from this study, the Dolleman ice core and acid-doped ice agree with each other within the error range. The conductance at -22℃ increases monotonically from 300kHz to 1MHz. This tendency is not caused by the system but by impurities in the specimen. The ratio between the conductance at 300kHz and at 1MHz is 0.845. This can not explain with one Debye dispersion. These results add basic knowledge for radio-echo soundings, especially at percolation zone in the ice cap.

Other Activities and Achievements

Books and other publications

  • 「女も男もフィールドへ」(百万人のフィールドワーカーシリーズ12)               
    椎野若菜, 的場澄人
    古今書院, Apr. 2017, 224, Japanese, General book, [Joint editor]
  • 低温科学便覧               
    的場 澄人, 8章8.5環オホーツク地域の山岳氷河
    丸善出版, 2016, [Joint work]
  • アイスランド・グリーンランド・北極を知るための65章               
    的場 澄人, 「グリーンランドの都市、カナック—グリーンランド人の心のふるさと」、「世界遺産①・イルリサット・アイスフィヨルド」、「地球温暖化とグリーンランド氷床」
    明石書店, 2016, 441, [Joint work]
  • 雪と氷の疑問60(みんなが知りたいシリーズ2)               
    的場 澄人, グリーンランドはどんなところ?、フロストフラワーとは何ですか?
    2016, [Joint work]
  • フィールドに入る(100万人のフィールドワーカーズシリーズ1)               
    的場 澄人, 5.のこのこと犬ソリにのって—北極探検家と行くフィールドワーク
    古今書院, May 2014, [Joint work]
  • 積雪観測ガイドブック               
    的場 澄人, 化学分析のための積雪試料採取
    朝倉書店, 2010, [Joint work]
  • なぞの宝庫・南極大陸               
    技術評論社, 2008
  • 身近な気象・気候調査の基礎               
    古今書院, 2000

Lectures, oral presentations, etc.

  • 寒冷地対応型小型ポータブル PM2.5測定装置の開発 -冬季札幌観測,夏季アラスカ森林火災事例,函館黄 砂事例の紹介-
    安成哲平, 若林成人, 松見豊, 的場澄人
    雪氷研究大会(2021・千葉ーオンライン), 16 Sep. 2021, Japanese, Oral presentation
    30109798
  • グリーンランド・カナック氷帽上 SIGMA-B サイトで観測された雲の有無による表面熱収支の違い
    西村基志, 青木輝夫, 庭野匡思, 的場澄人, 谷川朋範, 山口悟, 山崎哲秀
    雪氷研究大会(2021・千葉ーオンライン), 15 Sep. 2021, Japanese, Poster presentation
    30109798
  • グリーンランド南東ドームにおけるアイスコア掘削と気象・雪氷観測
    飯塚芳徳, 的場澄人, 箕輪昌紘, 山崎哲秀, 川上薫, 角五綾子, 宮原盛厚, 藤田耕史, 橋本明弘, 庭野匡思, 谷川朋範, 青木輝夫
    雪氷研究大会(2021・千葉ーオンライン), 15 Sep. 2021, Japanese, Poster presentation
    30109798
  • 札幌で 2021 年 2 月に発生した斑点濡れ雪の氷薄片観察               
    波多俊太郎, 日下稜, 原田康浩, 庭野匡思, 的場澄人
    雪氷研究大会(2021・千葉ーオンライン), 15 Sep. 2021, Japanese, Poster presentation
  • 〔Major achievements〕2021 年 2 月にグリーンランドシオラパルクで生じた海氷流出-海氷の脆弱性が将来の地域住民の生活に 与える影響-
    的場澄人, 山崎哲秀, 青木輝夫
    雪氷研究大会(2021・千葉ーオンライン), 15 Sep. 2021, Japanese, Oral presentation
    30109798
  • 光吸収性不純物粒子を介した大気-積雪相互作用に関する研究の新展開               
    庭野匡思, 梶野瑞王, 梶川友貴, 青木輝夫, 兒玉 裕二, 谷川朋範, 的場澄人
    雪氷研究大会(2021・千葉ーオンライン), 15 Sep. 2021, Japanese, Oral presentation
  • ネパール・ヒマラヤ, トランバウ氷河アイスコアの水安定同位体分析               
    川上薫, 飯塚芳徳, 的場澄人, 青木輝夫, 杉山慎, 安藤卓人
    雪氷研究大会(2021・千葉ーオンライン), 15 Sep. 2021, Japanese, Oral presentation
  • 〔Major achievements〕高時間分解能アイスコアによる近年の北大西洋植物プランクトンブルームの長期化の解明
    黒﨑豊, 的場澄人, 飯塚芳徳, 藤田耕史, 島田利元
    雪氷研究大会(2021・千葉ーオンライン), 13 Sep. 2021, Japanese, Oral presentation
    30109798
  • ネパール・ヒマラヤ, トランバウ氷河アイスコアの水安定同位体分析               
    江刺和音, 對馬あかね, 植村立, 飯塚芳徳, 的場澄人, 藤田耕史
    雪氷研究大会(2021・千葉ーオンライン), 13 Sep. 2021, Japanese, Oral presentation
  • グリーンランドで掘削されたアイスコア中の過去 100 年間の鉱物組成変動
    永塚尚子, 東久美子, 對馬あかね, 藤田耕史, 的場澄人, 大沼友貴彦, Remi Dallmayr, 門田萌, 平林幹啓, 尾形純, 塚川佳美, 北村享太郎, 箕輪昌紘, 小室悠紀, 本山秀明, 青木輝夫, 中澤文男, Trevor James Popp, Dorthe Dahl-Jensen
    雪氷研究大会(2021・千葉−オンライン), 13 Sep. 2021, Japanese
    12352095
  • The version upgrade of the GCOM-C/SGLI Cryosphere products               
    Rigen Shimada, Masahiro Hori, Teruo Aoki, Tomonori Tanikawa, Sumito Matoba, Masashi Niwano, Knut Stamnes, Wei Li, Nan Chen
    The 11th Symposium on Polar Science, 03 Dec. 2020, English, Oral presentation
  • Continuous flow analysis of iron oxide in a Greenland ice core using a modified single-particle soot photometer
    Goto-Azuma, K, thers
    The 11th Symposium on Polar Science, 03 Dec. 2020, English, Oral presentation
    12352095
  • Analysis of solid microparticles and metal components contained in snow at EGRIP, Greenland               
    Komuro, Y, thers
    The 11th Symposium on Polar Science, 03 Dec. 2020, English, Oral presentation
  • 〔Major achievements〕ArCS II Cryosphere research-3 "Water and material circulations between snow-and-ice and atmosphere in seasonal sea ice regions and their impact on environment in the Arctic
    Sumito Matoba, Yoshinori Iizuka, Yuzo Miyazaki, Toshitaka Suzuki, Shohei Hattori, Ryu Uemura, Keiichiro Hara, Naga Oshima, Tetsuhide Yamasaki, Teruo Aok
    The 11th Symposium on Polar Science, 03 Dec. 2020, English, Poster presentation
    30109798
  • Temporal and spatial variabilities in recent surface mass balance at EGRIP, Greenland               
    Yuki Komuro, Fumio Nakazawa, Naoko Nagatsuka, Motohiro Hirabayashi, Wataru Shigeyama, Sumito Matoba, Tomoyuki Homma, Kumiko Goto- Azuma
    The 11th Symposium on Polar Science, 03 Dec. 2020, English, Poster presentation
  • The relation between sea ice stratigraphy and particle concentration in an Alaskan coastal lagoon               
    Masato Ito, Andrew R. Mahoney, Chris M. Polashenski, Takenobu Toyota, Sumito Matoba, Takashi Kikuch
    The Eleventh Symposium on Polar Science, 03 Dec. 2020, English, Poster presentation
  • グリーンランド・カナック氷帽上SIGMA-Bにおける気象条件の経年変動
    西村基志, 青木輝夫, 庭野匡思, 的場澄人, 谷川朋範, 山口悟, 山崎 哲秀
    雪氷研究大会(2020・オンライン), 18 Nov. 2020, Japanese, Poster presentation
    30109798
  • ArCS II 雪氷サブ課題3「季節海氷域における雪氷-大気間の物質・水循環解明とその気候への影響評 価」の紹介
    的場澄人, 飯塚芳徳, 宮﨑雄三, 鈴木利孝, 服部祥平, 植村立, 原圭一郎, 大島長, 山崎哲秀, 青木輝夫
    雪氷研究大会(2020・オンライン), 18 Nov. 2020, Japanese, Poster presentation
    30109798
  • グリーンランドEGRIPのピット試料に含まれる固体微粒子および金属成分の解析               
    小室悠紀 ほか
    雪氷研究大会(2020・オンライン), 18 Nov. 2020, Japanese, Poster presentation
  • 積雪と海氷の波長別偏光特性               
    谷川朋範, 青木輝夫, 石元裕史, 増田一彦, 庭野匡思, 堀雅裕, 八久保 晶弘, 的場澄人, 杉浦幸之助, 島田利元, 大河原望
    雪氷研究大会(2019・オンライン), 18 Nov. 2020, Japanese, Oral presentation
  • グリーンランド氷床上における衛星抽出積雪物理量とアルベドの関係               
    青木輝夫, 島田利元, 堀雅裕, 庭野匡思, 谷川朋範, 的場澄人
    雪氷研究大会(2020・オンライン), 17 Nov. 2020, Japanese, Oral presentation
  • グリーンランド南東ドームアイスコアによる 1970 年代の硫酸エアロゾル組成とフラックス               
    飯塚芳徳, 植村立, 松井仁志, 大島長, 的場澄人
    雪氷研究大会(2020・オンライン), 17 Nov. 2020, Japanese, Oral presentation
  • グリーンランド北西部 SIGMA-A アイスコアの融解再凍結層に含まれる不純物の解析               
    川上薫, 飯塚芳徳, 的場澄人, 青木輝夫, 杉山慎, 安藤卓人
    雪氷研究大会(2020・オンライン), 17 Nov. 2020, Japanese, Oral presentation
  • Atmospheric sea-salt and halogen chemistry in the Antarctic region               
    Keiichiro Hara, Kazuo Osada, Masanori Yabuki, Sumito Matoba, Fumio Nakazawa, Shuji Fujita, Motohiro Hirabayashi, Takashi Yamanouchi
    The Tenth Symposium on Polar Science, 05 Dec. 2019, English, Oral presentation
  • Variations in mineralogical composition of dust present in the Greenland SIGMA-D ice core and EGRIP snow pit over the past 100 years               
    Naoko Nagatsuka, Kumiko Goto-Azuma, Akane Tsushima, Hideaki Motoyama, Sumito Matoba, Koji Fujita, Tetsuhide Yamasaki, Yukihiko Onuma, Yuki Komuro, Masahiro Minowa, Teruo Aoki, Motohiro Hirabayashi, Fumio Nakazawa, Dorthe Dahl-Jensen
    The tenth symposium on Polar Science, 05 Dec. 2019, English, Oral presentation
  • Satellite-derived snow grain size over the Greenland Ice Sheet and its relationships with climate indices
    Teruo Aoki, Rigen Shimada, Masahiro Hori, Masashi Niwano, Tomonori Tanikawa, Hiroshi Ishimoto, Sumito Matoba, Iizuka Yoshinori, Koji Fujita
    The Tenth Symposium on Polar Science, 04 Dec. 2019, English, Oral presentation
    12352095
  • Antarctic Study on Tropospheric Aerosol and Snow Chemistry (ASTASC) in JARE Phase X               
    Keiichiro Hara, Masanori Yabuki, Hiroshi Kobayashi, Sumito Matoba, Yoshinori Iizuka, Norimichi Takenaka, Shohei Hattori, Hisahiro Takashima, Fumihisa Kobayashi, Sakiko Ishino, Naohiko Hirasawa, Masahiko Hayashi
    The Tenth Symposium on Polar Science, 03 Dec. 2019, English, Oral presentation
  • 2007-2018 年冬季の札幌の表面積雪中の EC、OC および dust 濃度の変動傾向               
    對馬あかね, 庭野匡思, 青木輝夫, 谷川 朋範, 的場澄人, 大河原望
    雪氷研究大会(2019・山形), 10 Sep. 2019, Japanese, Oral presentation
    09 Sep. 2019 - 11 Sep. 2019
  • 過去の気候変動復元を目的とした地下氷のイオン濃度解析               
    飯塚芳徳, 宮本千尋, 的場澄人, 岩花剛, 堀内一穂, 高橋嘉夫, 漢那直也, 鈴木光次, 大野浩
    雪氷研究大会(2019・山形), 10 Sep. 2019, Japanese, Oral presentation
    08 Sep. 2019 - 11 Sep. 2019
  • グリーンランド氷床アイスコアおよび積雪ピットサンプル中の過去100年間の鉱物組成変動の解明
    永塚尚子, 東久美子, 對馬あかね, 本山秀明, 的場澄人, 藤田耕史, 山崎哲秀, 大沼友貴彦, 小室悠紀, 箕輪昌紘, 青木輝夫, 平林幹啓, 中澤文男, Dorthe Dahl-Jensen
    雪氷研究大会(2019・山形), 11 Sep. 2019, Japanese, Oral presentation
    12352095
  • アイスメモリープロジェクトに対する日本雪氷コミュニティの貢献の可能性―これまでの経緯とこれ からの課題と展望―               
    服部祥平, 藤田耕史, 竹内望, 飯塚芳徳, 的場澄人
    雪氷研究大会(2019・山形), 10 Sep. 2019, Japanese, Poster presentation
  • 積雪の国際分類の日本語版作成について -積雪分類ワーキンググループの活動-               
    尾関俊浩, 八久保晶弘, 原田裕介, 鎌田慈, 勝島隆史, 的場澄人, 本吉弘岐, 榊原健一, 竹内由香里, 山口悟, 西村浩一
    雪氷研究大会(2019・山形), 10 Sep. 2019, Japanese, Oral presentation
  • グリーンランド北西部における過去 350 年間のブラックカーボン及びダストの季節変化及び経年変化
    東久美子他
    雪氷研究大会(2019・山形), 10 Sep. 2019, Japanese, Oral presentation
    12352095
  • グリーンランド北西部 SIGMA-A アイスコアによる海氷変動の復元               
    黒﨑豊, 的場澄人, 飯塚芳徳, 庭野匡思, 谷川朋範, 安藤卓人, 青木輝夫
    雪氷研究大会(2019・山形), 10 Sep. 2019, Japanese, Oral presentation
  • グリーランド北西部 SIGMA-A アイスコアの融解再凍結層に含まれる微粒子の観察と組成分析
    川上薫, 飯塚芳徳, 的場澄人, 青木輝夫, 杉山慎, 安藤卓人
    雪氷研究大会(2019・山形), 10 Sep. 2019, Japanese, Oral presentation
    12352095
  • フィルンコア試料を用いたグリーンランド南東部高涵養域における過去60年間の気候変動に伴った雪質変化の評価
    安藤卓人, 飯塚芳徳, 柴田麻衣, 的場澄人, 杉山慎, 飯塚芳徳, 柴田麻衣, 的場澄人, 杉山慎, 安達聖, 山口悟, 藤田耕史, 堀彰, 青木輝夫, 藤田秀二
    日本地球惑星科学連合大会予稿集(Web), 2019, Japanese
    2019 - 2019
  • 光吸収性エアロゾルの監視と大気・雪氷系の放射収支への影響評価
    保坂征宏, 谷川朋範, 庭野匡思, 足立光司, 石元裕史, 大島長, 梶野瑞王, 的場澄人
    日本気象学会大会講演予稿集, 30 Sep. 2018, Japanese
    30 Sep. 2018 - 30 Sep. 2018
  • 積雪内部における鉛直高解像度不純物移動計算の試み
    庭野匡思, 青木輝夫, 青木輝夫, 梶野瑞王, 梶野瑞王, 伊藤一輝, 橋本明弘, 兒玉裕二, 的場澄人, 谷川朋範, 山口悟
    日本気象学会大会講演予稿集, 30 Apr. 2018, Japanese
    30 Apr. 2018 - 30 Apr. 2018
  • Effect of snow impurities on radiation budget in Sapporo
    Hirozawa Yoichiro, Aoki Teruo, Niwano Masashi, Matoba Sumito, Kodama Yuji, Tanikawa Tomonori
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2018, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2018 - 2018
  • Past 60 years changes in oxidation pathways of tropospheric sulfur from triple oxygen isotopic composition of sulfate preserved in SE-Dome ice core
    Hattori Shohei, Iizuka Yoshinori, Uemura Ryu, Suzuki Nozomi, Tsuruta Asuka, Ishino Sakiko, Fujita Koji, Matoba Sumito, Yoshida Naohiro
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 2018, GEOCHEMICAL SOCIETY OF JAPAN, Japanese
    2018 - 2018, グリーンランドの氷床コアは北アメリカやヨーロッパ由来の大気が由来し、過去のエアロゾル動態を復元する貴重な環境媒体である。産業革命以降の人間活動の増大に伴い、大気中に放出される硫黄及び窒素酸化物の濃度が上昇し、1970年以降に北アメリカ、ヨーロッパで排出が抑制された。事実、氷床コア中の硫酸濃度の減少がSO2排出量の減少と対応していることが知られている。本研究では、グリーンランド南東ドーム(SE-Dome)で採取された約90 m、60年分のアイスコアを用い、時間解像度3~6年で硫酸の三酸素同位体組成を分析した。
  • High-resolution analysis of black carbon in an ice core drilled at Northwest Greenland
    Goto-Azuma Kumiko, Matoba Sumito, Kadota Moe, Aoki Teruo, Moteki Nobuhiro, Ohata Sho, Mori Tatshuhiro, Koike Makoto, Komuro Yuki, Tsushima Akane, Nagatsuka Naoko, Ogawa-Tsukagawa Yoshimi, Fujita Koji, Kondo Yutaka, Dallmayr Remi, Hirabayashi Motohiro, Ogata Jun, Kitamura Kyotaro, Kawamura Kenji, Motoyama Hideaki
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2018, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2018 - 2018
  • Development of Handheld Integrating Sphere Snow Grain Sizer (HISSGraS)
    青木輝夫, 青木輝夫, 庭野匡思, 山口悟, 的場澄人, 谷川朋範, 堀雅裕, 島田利元, 本吉弘岐, 八久保晶弘
    雪氷研究大会講演要旨集(Web), 2018, Japanese
    2018 - 2018
  • 北西グリーンランド氷床上SIGMA‐Aサイトにおける雪面熱収支
    廣瀬聡, 青木輝夫, 青木輝夫, 庭野匡思, 的場澄人, 谷川朋範, 山口悟, 山崎哲秀
    日本地球惑星科学連合大会予稿集(Web), 2018, Japanese
    2018 - 2018
  • SIGMA-Traverse 2018: Dog sledge traverse expedition on the northwestern Greenland ice sheet to perform multipoint snow/ice physical measurements
    庭野匡思, 山口悟, 山崎哲秀, 青木輝夫, 青木輝夫, 橋本明弘, 谷川朋範, 保坂征宏, 的場澄人
    雪氷研究大会講演要旨集(Web), 2018, Japanese
    2018 - 2018
  • グリーンランド SIGMA-A アイスコア試料の近赤外光反射率測定
    安藤卓人, 飯塚芳徳, 的場澄人, 杉山慎, 柴田麻衣, 黒崎豊, 堀彰, 八久保晶弘, 藤田秀二, 青木輝夫
    雪氷研究大会講演要旨集(Web), 2018, Japanese
    2018 - 2018
  • グリーンランド氷床における極域気候モデルNHM‐SMAPの2m気温再現精度
    庭野匡思, 青木輝夫, 青木輝夫, 橋本明弘, 的場澄人, 山口悟, 谷川朋範, 藤田耕史, 對馬あかね, 飯塚芳徳, 島田利元, 堀雅裕
    日本気象学会大会講演予稿集, 30 Sep. 2017, Japanese
    30 Sep. 2017 - 30 Sep. 2017
  • Seasonal scale dating of a shallow ice core from Greenland using oxygen isotope matching between data and simulation
    Furukawa Ryoto, Uemura Ryu, Fujita Koji, Sjolte Jesper, Yoshimura Kei, Matoba Sumito, Iizuka Yoshinori
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 2017, GEOCHEMICAL SOCIETY OF JAPAN, Japanese
    2017 - 2017,

  • The past 60 years variation of nitrogen isotopic composition of nitrate preserved in SE-Dome site, southeastern Greenland Ice Sheet
    Tsuruta Asuka, Hattori Shohei, Iizuka Yoshinori, Fujita Koji, Uemura Ryu, Matoba Sumito, Yoshida Naohiro
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 2017, GEOCHEMICAL SOCIETY OF JAPAN, Japanese
    2017 - 2017,

  • Analysis of insoluble particles in the ice core from south-east dome, Greenland
    Amino Tomomi, Iizuka Yoshinori, Matoba Sumito
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2017 - 2017
  • Understanding variation trend of δ17O and 17O-excess in an ice core drilled at the SIGMA-D site
    Tsushima Akane, Gkinis Vasileios, Goto-Azuma Kumiko, Matoba Sumito, Nagatsuka Naoko, Motoyama Hideaki, Fujita Koji, Aoki Teruo
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2017 - 2017
  • The past 60 years variations of sources and formation pathways of nitrate preserved in SE-Dome site, southeastern Greenland Ice Sheet
    Tsuruta Asuka, Hattori Shohei, Iizuka Yoshinori, Fujita Koji, Uemura Ryu, Matoba Sumito, Yoshida Naohiro
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2017 - 2017
  • Reconstruction of paleoclimate past 100 years from ice core at northwestern Greenland Ice Sheet
    Kurosaki Yutaka, Matoba Sumito, Iizuka Yoshinori, Aoki Teruo, Sugiyama Shin
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2017, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2017 - 2017
  • 「北極域における積雪汚染及び雪氷微生物が急激な温暖化に及ぼす影響評価に関する研究(SIGMAプロジェクト)」によるグリーンランド観測               
    青木輝夫, 庭野匡思, 谷川朋範, 橋本明弘, 的場澄人, 杉山慎, 竹内望, 本山秀明, 永塚尚子, 植竹淳, 堀雅裕, 島田利元, 山口悟, 藤田耕史, 山崎哲秀
    極地, 2017, Japanese
    2017 - 2017
  • Performance of the polar regional climate model NHM-SMAP applied in Greenland Ice Sheet
    庭野匡思, 青木輝夫, 青木輝夫, 橋本明弘, 的場澄人, 山口悟, 谷川朋範, 藤田耕史, 對馬あかね, 飯塚芳徳, 島田利元, 堀雅裕
    雪氷研究大会講演要旨集(Web), 2017, Japanese
    2017 - 2017
  • Automatic weather station in polar region: SIGMA and JARE
    本山秀明, 本山秀明, 青木輝夫, 庭野匡思, 的場澄人, 杉山慎, 山口悟, 平沢尚彦, 平沢尚彦, 川村賢二, 川村賢二, 三戸洋介, 藤原宏章, 小野文睦, 森陽樹
    雪氷研究大会講演要旨集(Web), 2017, Japanese
    2017 - 2017
  • 極域領域気候モデルNHM‐SMAPの初期評価結果
    庭野匡思, 青木輝夫, 青木輝夫, 橋本明弘, 谷川朋範, 保坂征宏, 堀雅裕, 的場澄人, 山口悟, 藤田耕史, 本山秀明
    日本気象学会大会講演予稿集, 30 Sep. 2016, Japanese
    30 Sep. 2016 - 30 Sep. 2016
  • グリーンランド氷床上SIGMA‐Aサイトにおける放射収支観測―近赤外アルベドと気温の関係―
    青木輝夫, 青木輝夫, 庭野匡思, 谷川朋範, 的場澄人, 山口悟, 山崎哲秀, 藤田耕史, 本山秀明, 堀雅裕
    日本気象学会大会講演予稿集, 30 Sep. 2016, Japanese
    30 Sep. 2016 - 30 Sep. 2016
  • Temperature and accumulation rate reconstructions from the ice core in south-east dome, Greenland
    Furukawa Ryoto, Iizuka Yoshinori, Matoba Sumito, Uemura Ryu
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2016, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2016 - 2016
  • The next deep ice coring in the Dome Fuji region, East Antarctica
    Kawamura Kenji, Motoyama H., Goto-Azuma K., Fujita S., Furukawa T., Nakazawa F., Aoki S., Azuma N., Abe-Ouchi A., Iizuka Y., Uemura R., Uchida T., Oono H., Kameda T., Suzuki T., Takata M., Hirabayashi M., Fujita K., Fukui K., Hori A., Horiuchi K., Matoba S., Miyamoto A.
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2016, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2016 - 2016
  • Variability of black carbon in Greenland during the past 350 years at the SIGMA-D site - Preliminary results from Continuous Flow Analysis –
    Goto-Azuma Kumiko, Matoba Sumito, Kadota Moe, Aoki Teruo, Moteki Nobuhiro, Ohata Sho, Mori Tatshuhiro, Koike Makoto, Komuro Yuki, Tsushima Akane, Nagatsuka Naoko, Ogawa-Tsukagawa Yoshimi, Yutaka Yutaka, Dallmayr Remi, Hirabayashi Motohiro, Ogata Jun, Kitamura Kyotaro, Kawamura Kenji, Motoyama Motoyama
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2016, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2016 - 2016
  • Darkening of Greenland ice sheet and satellite-derived snow parameters               
    T. Aoki
    6th Symposium on Polar Science, 18 Dec. 2015, English, Oral presentation
    [International presentation]
  • Sea-salt fractionation in Arctic during winter               
    K. Hara, S. Matoba, T. Yamasaki
    6th Symposium on Polar Science, 16 Dec. 2015, English, Poster presentation
    [International presentation]
  • Glaciological Investigations in Severnaya Zemlya in 1995-1996               
    S. Takahashi, S. Matoba, A. Takahashi, O. Watanabe, L. Savatyugin
    6th Symposium on Polar Science, 16 Dec. 2015, Japanese, Poster presentation
    [International presentation]
  • Ice core drilling on the South-East Dome in Greenland Ice Sheet               
    Y. Iizuka, S. Matoba, T. Yamasaki, I. Oyabu, M. Kadota
    The 6th Symposium on Polar Science, 16 Dec. 2015, English, Poster presentation
    [International presentation]
  • Chemical concentrations and fractionations during formation of frost flower on sea ice               
    S. Matoba, K. Hara, T. Yamasaki, M. Hirabayashi
    The 6th Symposium on Polar Science, 16 Dec. 2015, Japanese, Oral presentation
    [International presentation]
  • Reconstruction of climate during the past 157 years by analyzing an ice core obtained from Northwestern Greenland Ice Sheet (SIGMA-D)               
    Moe Kadota, Sumito Matoba, Hideaki Motoyama, Koji Fujita, Tetsuhide Yamasaki, Yukihiko Onuma, Masahiro Minowa, Yuki Komuro, Teruo Aoki
    The 6th Symposium on Polar Science, 16 Dec. 2015, Japanese, Oral presentation
    [International presentation]
  • Observation of the snow pit and atmospheric aerosols at the South-East Dome in Greenland
    Oyabu Ikumi, Iizuka Yoshinori, Matoba Sumito, Yamasaki Tetsuhide, Kadota Moe
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2015, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2015 - 2015
  • Reconstruction of climate during the past 157years by analyzing an ice core obtained from Northwestern Greenland Ice Sheet (SIGMA-D)
    Kadota Moe, Matoba Sumito, Motoyama Hideaki, Fujita Koji, Yamasaki Tetsuhide, Onuma Yukihiko, Minowa Masahiro, Komuro Yuki, Aoki Teruo
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2015, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2015 - 2015
  • Analysis of the total concentration of metals in the Greenland, SIGMA-D shallow ice core
    Komuro Yuki, Suzuki Toshitaka, Onuma Yukihiko, Minowa Masahiro, Yamasaki Tetsuhide, Matoba Sumito, Fujita Koji, Hirabayashi Motohiro, Motoyama Hideaki, Aoki Teruo
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2015, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2015 - 2015
  • Advocates of establishment of observation bases in Greenland Arctic and Canada Arctic region -For promotion of Japanese Arctic Research -               
    Tetsuhide Yamasaki, AVANGNAQ, Masayuki Kobayashi (APEROS, Sumito Matoba, ILT
    Symposium on Polar Science, 02 Dec. 2014, English, Poster presentation
    [International presentation]
  • Temperature effect on rate of decrease in specific surface area (SSA) of snow under isothermal metamorphysm               
    Akihiro Hachikubo (KIT, Satoru Yamaguchi (NIED, Masahiro Hori (JAXA, Tomonori Tanikawa (JAXA, Konosuke Sugiura, niv. Toyama, Sumito Matoba (ILTS, Masashi Niwano (MRI, Katsuyuki Kuchiki (MRI, Teruo Aoki (MRI
    Symposium on Polar Science, 02 Dec. 2014, English, Poster presentation
    [International presentation]
  • Chemical compositions of frost flower at Siorapaluk in northwestern Greenland               
    Sumito Matoba (ILTS, Hokkaido Univ, Keiichiro Hara, Fukuoka Univ, Tetsuhide Yamasaki, AVANGNAQ
    Symposium on Polar Science, 02 Dec. 2014, English, Poster presentation
    [International presentation]
  • Aerosol measurements at Siorapaluk, Greenland               
    K. Hara, S. Matoba, T. Yamasaki, Fukuoka Univ, Hokkaido Univ. ILTS, AVANGNAQ
    Symposium on Polar Science, 02 Dec. 2014, English, Poster presentation
    [International presentation]
  • Preliminary results of an ice core obtained from Northwestern Greenland Ice Sheet (SIGMA-D)               
    Sumito Matoba (ILTS, Hokkairo Uni, Hideaki Motoyama (NIPR, Koji Fujita, Nagoya Uni, Tetsuhide Yamasaki, AVANGNAQ, Yukihiko Onuma, Chiba Uni, Masahiro Minowa, Hokkaido Uni, Yuki Komuro, Yamagata Univ, Moe Kadota, Hokkaido Uni, Satoru Yamaguchi (NIED, Teruo Aoki (MR
    Symposium on Polar Science, 02 Dec. 2014, English, Oral presentation
    [International presentation]
  • A development of snowfall estimation model for Antarctica *part1-               
    Kazue Suzuki (ISM, Hideaki Motoyama (NIPR, SOKENDAI, Naohiko Hirasawa (NIPR, SOKENDAI, Takashi Yamaonuchi (NIPR, SOKENDAI, Hiroyuki Enomoto (NIPR, SOKENDAI, Takeshi Tamura (NIPR, SOKENDAI, Yoshinori Iizuka (ILTS, Sumito Matoba (ILTS, Tomoyuki Higuchi (ISM, SOKENDAI
    Symposium on Polar Science, 02 Dec. 2014, English, Oral presentation
    [International presentation]
  • Recent technologies of intermediate depth drill and borehole measurement               
    Hideaki Motoyama, National, Institute of, Polar Research, Atsushi Furusaki, Asahikawa National, College of Technology, Akiyoshi Takahashi, Geo Tecs Co. Lt, Yoichi Tanaka, eosystems Inc, Morihiro Miyahara, Anori Inc, Morimasa Takata, Nagaoka, University of Technology, Takanobu Sawagaki, Faculty of, Env. Earth, Science Hokkaido University, Sumito Matoba, itute of Low, Temperature Science, Hokkaido University, Shin Sugiyama, stitute of Low, Temperature Science, Hokkaido University, Kunio Shinbori, Institute of Low, Temperature Science, Hokkaido University, Shoichi Mori, stitute of Low, Temperature Science, Hokkaido Univer
    Symposium on Polar Science, 02 Dec. 2014, Japanese, Oral presentation
    [Invited], [International presentation]
  • 日本雪氷学会による日本の雪と氷 100 選 web 参加型の企画の試み               
    山口悟, 的場澄人, 角川咲江, 原田鉱一郎, 堤拓弥, 宮崎伸夫, 本雪氷学会広報委員会, 澤柿教伸, 日, 本雪氷学会電子情報委
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Poster presentation
    [Domestic Conference]
  • グリーンランド北西部でのフロストフラワーの観測 化学成分の濃縮と成分分別               
    的場澄人, 道大学低温科学研究所, 原圭一郎, 山崎哲秀(アバンナット
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Poster presentation
    [Domestic Conference]
  • 融雪期における雪面上への模擬降雨散水実験 − 積雪底面流出水の水同位体比とイオン濃度の時間変化 −               
    石井吉之, 中坪俊一, 森章一, 的場澄人, 海道大学低温科学研
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Poster presentation
    [Domestic Conference]
  • フィンランド積雪縦断観測-2013               
    佐藤篤司, 防災科学技術研究所雪氷防災研究センター, 對馬あかね, 北海道大学大学院環境科学院, 大宮 哲, 的場澄人, 低温科学
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Poster presentation
    [Domestic Conference]
  • 最近の浅層・中層掘削技術と検層について               
    本山秀明, 古崎睦, 旭川工業高等専門学校, 高橋昭好, 地球工学研究, 田中洋 一, ジオシステムズ, 宮原盛厚, 株)アノウィ, 新堀邦夫, 的場澄人, 杉山慎, 森章一, 低温科学研究所, 澤柿教伸, 北海道大学大学院地球環境科学研究院, 高田守昌
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Poster presentation
    [Domestic Conference]
  • 融雪初期における積雪比表面積の深度プロファイルの経時変化               
    八久保晶弘, 山口悟, 防災科学技術研究所, 堀雅裕, 谷川朋範, 杉浦幸之助, 的場澄人, 学研究所, 庭野匡思, 朽木勝幸, 青木輝夫
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Poster presentation
    [Domestic Conference]
  • 札幌における光吸収性積雪不純物濃度の長期変動               
    朽木勝幸, 青木輝夫, 庭野匡思, 的場澄人, 低温科学研究所, 兒玉裕二
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Poster presentation
    [Domestic Conference]
  • 積雪粒径測定手法の比較               
    青木輝夫, 山口悟, 本吉弘岐, 朽木勝幸, 庭野匡思, 藤田耕史, 的場澄人, 八久保晶弘, 谷川朋範, 堀雅裕, 宇宙航空研究開発機構, 竹内由香里, 杉浦幸之助
    雪氷研究大会(2014・八戸), 22 Sep. 2014, Japanese, Oral presentation
    [Domestic Conference]
  • グリーンランド北西氷床のアイスコア掘削について - SIGMA-D 経過報告 -               
    本山秀明, 的場澄人, 大学低温科学研究所, 藤田耕史, 名古屋大学大学院環境学, 研究科, 山崎哲秀(アバンナット, 大沼友貴彦, 箕輪昌紘, 道大学低温, 科学研究所, 小室悠紀, 山形大学大学院理工学研究科, 山口悟(防災科学技術研究所雪氷防災研究センタ, 青木輝夫
    雪氷研究大会(2014・八戸), 21 Sep. 2014, Japanese, Oral presentation
    [Domestic Conference]
  • アイスコアを用いたアラスカの近年の気候変動復元               
    對馬あかね, 北海道大学大学院環境科学院, 的場澄人, 白岩孝行, 海道大学低温科学研
    雪氷研究大会(2014・八戸), 21 Sep. 2014, Japanese, Oral presentation
    [Domestic Conference]
  • グリーンランド氷床上積雪面における潜熱フラックス計算方法の再検討               
    庭野匡思, 青木輝夫, 的場澄人, 山口悟, 谷川朋範, 朽木勝幸, 本山秀明
    2014年秋季気象学会, Sep. 2014, Japanese, Oral presentation
    [Domestic Conference]
  • Impacts of new snow grain size setup on the performance of a physical snowpack model SMAP
    Masashi Niwano, Teruo Aoki, Katsuyuki Kuchiki, Sumito Matoba, Yuji Kodama
    Japan Geoscience Union Meeting 2014, May 2014, Japanese, Oral presentation
    [Domestic Conference]
  • Alpine ice core drilling at the northern North Pacific region               
    Matoba, S, Shimbori, K, Shiraiwa, T
    7th International Workshop on Ice Drilling Technology, 10 Sep. 2013, English, Oral presentation
    [International presentation]
  • 浅層掘削記録、深層掘削記録の解析と将来の浅層・中層掘削計画               
    本山秀明, 古崎睦, 旭川工業高等専門学校, 高橋昭好, 地球工学研, 田中洋一, ジオシステムズ, 宮原盛厚, アノウィ, 新堀邦夫, 的場澄人, 杉山慎, 北海道, 大学低温科学研究所, 高田守昌
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Oral presentation
    [Domestic Conference]
  • 積雪温度勾配下における水蒸気移動とそれに伴う水安定同位体変化               
    保科優, 山口悟(防災科学技術研究所雪氷防災センター, 藤田耕史, 佐 藤篤司, 術研究所雪氷防災センター, 的場澄人, 本山秀明
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Oral presentation
    [Domestic Conference]
  • グリーンランド氷床北西部 SIGMA-A サイトにおける過去 36 年間の年間質量収支の復元               
    的場澄人, 北海道大学低温科学研究所, 山口悟(防災科学技術研究所雪氷防災研究センター, 山崎 哲秀, 地球工学研, 青木輝夫, 庭野匡思, 谷川朋範, 本山秀明, 杉山慎(北海道大学低温科学研究
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Oral presentation
    [Domestic Conference]
  • グリーンランド氷床上積雪の通年数値シミュレーション               
    庭野匡思, 青木輝夫, 的場澄人, 学低温科学研究所, 山口悟(防災科学技術, 研究所雪氷防災研究センター, 谷川朋範, 朽木勝幸, 橋本明弘, 保坂征宏
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Oral presentation
    [Domestic Conference]
  • 積雪の波長別双方向反射率と偏光度の測定               
    谷川朋範, 青木輝夫, 堀雅裕, 宇宙航空研究開発機構, 八久 保晶弘, 杉浦幸之助, 的場澄人, 山口悟, 防災科学, 技術研究所, 朽木勝幸, 庭野匡思
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Poster presentation
    [Domestic Conference]
  • 雪氷面熱赤外域射出輝度の変動特性と表面雪質の関係               
    堀雅裕, 宇宙航空研究開発機構, 青木輝夫, 谷川朋範, 朽木 勝幸, 庭野匡思, 山口悟(防災科学技術研究所雪氷防災研究センター, 的場澄人, 北海, 道大学低温科学研, 八久保晶弘, 杉浦幸之助
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Oral presentation
    [Domestic Conference]
  • 近赤外域イメージセンサーによる積雪及び氷試料の光学測定               
    青木輝夫, 庭野匡思, 山口悟, 本吉弘岐, 防災科学技術研究所雪氷防災研究センター, 朽木勝幸, 的場澄人, 八久保晶弘
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Oral presentation
    [Domestic Conference]
  • 降雨と融雪が重なって生じる融雪出水(その 3) − 3 ヶ年の模擬降雨散水実験の比較−               
    石井吉之, 中坪俊一, 森章一, 的場澄人, 大学低温科学研究
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Poster presentation
    [Domestic Conference]
  • 南極ドームふじでの深層掘削孔の検層観測               
    本山秀明, 古崎睦, 高橋昭好, 田中洋一, 宮原盛厚, 高田守昌, 澤柿教伸, 的場澄人, 杉山慎, 新堀邦夫, 森章一
    雪氷研究大会(2013・北見), Sep. 2013, Japanese, Poster presentation
    [Domestic Conference]
  • Assessing the extreme surface melt at SIGMA-A, northwestern Greenland during 2012 summer using a physical snowpack model               
    Masashi Niwano, Teruo Aoki, Sumito Matoba, Satoru Yamaguchi, Tomonori Tanikawa, Hideaki Motoyama, Katsuyuki Kuchiki
    Japan Geophysical Union Meeting 2013, May 2013, Japanese, Oral presentation
    [Domestic Conference]
  • Possible effects of snow grain size and snow impurity concentration on the albedo mea- sured at SIGMA-A in Greenland               
    Teruo Aoki, Sumito Matoba, Satoru Yamaguchi, Tomonori Tanikawa, Masashi Niwano, Tetsuhide Yamasaki, Katsuyuki Kuchiki, Hideaki Motoyama, Masahiro Hori
    Japan Geoscience Union Meeting 2013, May 2013, Japanese, Oral presentation
    [Domestic Conference]
  • ICE MASS LOSS IN NORTHWESTERN GREENLAND               
    S.Sugiyama, S.Matoba, S.Yamaguchi, D.Sakakibara, S.Matsuno
    International Symposium on the Arctic Research, 17 Jan. 2013, English, Oral presentation
    [International presentation]
  • THE VARIABILITY MECHANISM OF PRECIPITATION AMOUNT IN CENTRAL ALASKA               
    A.Tsushima, S.Matoba, T.Shiraiwa
    International Symposium on the Arctic Research, 17 Jan. 2013, English, Poster presentation
    [International presentation]
  • THINNING OF AN ICE CAP AT THE COASTAL MARGIN OF NORTHWESTERN GREENLAND               
    S.Matsuno, S.Sugiyama, D.Sakakibara, S.Yamaguchi, S.Matoba, T. Sawagaki
    International Symposium on the Arctic Research, 16 Jan. 2013, English, Poster presentation
    [International presentation]
  • MASS CONCENTRATION OF SNOW IMPURITIES AND SNOW GRAIN SIZE ON NORTHWESTERN GREENLAND ICE SHEET: COMPARISON BETWEEN RETRIEVAL FROM MODIS AND IN-SITU MEASUREMENT               
    K. Kuchiki, T. Aoki, H. Motoyoshi, S. Matoba, S. Yamaguchi, T. Tanikawa, M.Niwano, R.Shimada, T.Yamasaki
    International Symposium on the Arctic Research, 16 Jan. 2013, English, Poster presentation
    [International presentation]
  • NUMERICAL SIMULATION OF SUMMER SNOWMELT AT SITE SIGMA-A NORTHWESTERN GREENLAND DURING 2012 INTENSIVE OBSERVATIONS               
    M. Niwano, T. Aoki, S. Yamaguchi, S. Matoba, T. Tanikawa, T. Yamasaki, K.Kuchiki, H.Motoyama
    International Symposium on the Arctic Research, 16 Jan. 2013, English, Poster presentation
    [International presentation]
  • MEASUREMENT OF SPECIFIC SURFACE AREA OF SNOW COVER IN 188 GREENLAND               
    S.Yamaguchi, S.Matoba, T.Aoki, M.Niwano, T.Tanikawa, T.Yamasaki, A. Hachikubo
    International Symposium on the Arctic Research, 16 Jan. 2013, English, Poster presentation
    [International presentation]
  • MELTING RECORD IN NORTHWESTERN GREENLAND ICE SHEET               
    S. Matoba, S. Yamaguchi, T. Yamasaki, T. Tanigawa, T. Aoki, M. Niwano, H. Motoyama
    International Symposium on the Arctic Research, 16 Jan. 2013, English, Poster presentation
    [International presentation]
  • INTENSIVE OBSERVATIONS OF METEOROLOGICAL AND SNOW-PHYSICAL 186 PARAMETERS AT SITE SIGMA-A IN NORTHWESTERN GREENLAND IN SUMMER 2012               
    T.Aoki, S.Matoba, S.Yamaguchi, T.Tanikawa, W.Niwano, T.Yamasaki, K.Kuchiki, H.Motoyama, M.Hori
    International Symposium on the Arctic Research, 16 Jan. 2013, English, Poster presentation
    [International presentation]
  • Variations of snow impurities and albedo at site SIGMA-A on Greenland ice sheet               
    Teruo Aoki (MRI, Katsuyuki Kuchiki (MRI, Sumito Matoba (ILTS, Satoru Yamaguchi, NIEDO, Tomonori Tanikawa (JAXA, Masashi Niwano (MRI, Tetsuhide Yamasaki, Arctic Explorer, Hideaki Motoyama (NIPR, Masahiro Hori (JA
    Symposium on Polar Science, 29 Nov. 2012, Japanese, Oral presentation
    [Domestic Conference]
  • Recent climatic change of Alaska (1724-2008) record from Aurora Peak ice core, central Alaska               
    Akane Tsushima, Hokkaido Univ.,ILTS, Sumito Matoba (ILTS, Takayuki Shiraiwa (ILT
    Symposium on Polar Science, 29 Nov. 2012, Japanese, Oral presentation
    [Domestic Conference]
  • Relation between annual accumulation reconstructed from ice cores at Alaskan alpine glaciers and Pacific Climate Shift               
    Sumito Matoba (ILTS, Hokkaido Univ, Akane Tsushima (ILTS, Grad. School for, Environ. Sci, Hokkaido Univ, Takayuki Shiraiwa (ILTS, Hokkaido Un
    Symposium on Polar Science, 29 Nov. 2012, Japanese, Oral presentation
    [Domestic Conference]
  • Glaciological observations at Site SIGMA-A on the northwestern Greenland Ice Sheet               
    Sumito Matoba (ILTS, Hokkaido Univ, Satoru Yamaguchi (Snow, Ice Research Center, NIED, Tetsuhide Yamasaki, Geo Tech Ltd, Arctic dog-sledge explorer, Teruo Aoki (MRI, Masashi Niwano (MRI, Tomonori Tanikawa, EORC , JAXA, Hideaki Motoyama (NIPR
    Symposium on Polar Science, 28 Nov. 2012, Japanese, Poster presentation
    [Domestic Conference]
  • Chemical properties of snow cover at the northwestern Greenland Ice Sheet
    Matoba Sumito, Uetake Jun, Aoki Teruo
    Summaries of JSSI and JSSE Joint Conference on Snow and Ice Research, 2012, The Japanese Society of Snow and Ice / Japan Society for Snow Engineering, Japanese
    2012 - 2012
  • Spectral albedos of glacier surfaces covered with glacial microbes in northwestern Greenland               
    青木輝夫, 朽木勝幸, 庭野匡思, 的場澄人, 植竹淳, 本山秀明, 竹内望
    Japan Geoscience Union Meeting, 2012, Japanese, Oral presentation
    [Domestic Conference]
  • Variations in pollen grains in an shallow ice core drilled from Fedchanko Glacier in Pamir, Central Asia.               
    宮入匡矢, 竹内望, 藤田耕史, 的場澄人, 岡本祥子, Dylan Bodinton, Eugene Podolskiy, Vlandimir Aizen
    Japan Geoscience Union Meeting, 2012, Japanese, Poster presentation
    [Domestic Conference]
  • Variation of precipitation reconstructed from Alaskan alpine ice-core               
    Matoba, S, A. Tsushima, T. Shiraiwa
    Japan Geoscience Union Meeting, 2012, Japanese, Oral presentation
    [Domestic Conference]
  • Variations in pollen grains in a shallow ice core drilled from Fechenko Glacier in Pamir, Central Asia               
    宮入匡矢, 竹内望, 藤田耕史, 的場澄人, 岡本祥子
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2012, Japanese, Poster presentation
    [Domestic Conference]
  • Study of precise measurement for borehole temperature in glacier and ice sheet               
    本山秀明, 古崎睦, 高橋宏, 高田守昌, 高橋昭好, 宮原盛厚, 的場澄人, 杉山慎, 飯塚芳徳, 新堀邦夫
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2012, Japanese, Poster presentation
    [Domestic Conference]
  • Chemical properties of snow cover at the northwestern Greenland Ice Sheet - Report on SIGMA 2011 Greenland expedition-               
    Matoba, S, J. Uetake, T. Aoki
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2012, Japanese, Poster presentation
    [Domestic Conference]
  • Field activities on Greenland Ice Sheet, 2012 by SIGMA project               
    青木輝夫, 的場澄人, 山口悟, 谷川朋範, 庭野匡思, 山崎哲秀, 朽木勝幸, 本山秀明, 堀雅裕
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2012, Japanese, Oral presentation
    [Domestic Conference]
  • Mass concentration of snow impurities in Sapporo during the 5 winters from 2007 to 2012               
    Kuchiki, K, T. Aoki, M. Niwano, Y. Kodama, S. Matoba
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2012, Japanese, Oral presentation
    [Domestic Conference]
  • Air-borne Fe deposition and solubility in precipitation estimated from alpine ice-core study
    Matoba Sumito, Sasaki Hirotaka, Shiraiwa Takayuki
    Abstracts of Annual Meeting of the Geochemical Society of Japan, 2011, GEOCHEMICAL SOCIETY OF JAPAN
    2011 - 2011, 近年行われた海洋への鉄散布実験の結果、北部北太平洋域の東西両海域において、鉄は一次生産の制限要因として重要であることが明らかになった。鉄の供給源については、下層からの鉛直的な供給と春先の黄砂の飛来によって大気を通してもたらさせる鉄フラックスの寄与が大きいと考えられているが、その寄与率について定量的な議論が十分なされていない。本研究では、アラスカの山岳氷河アイスコアから大気由来鉄の沈着量の経年変化を推定し、雪氷試料を用いた実験から黄砂から降水中に溶解する鉄量を求め、大気中の黄砂が海洋に湿性沈着したときに短期間で海洋環境に与えるインパクトを評価した。その結果、アイスコアから推定した鉄の年間沈着量は1993から2003年の平均で9.3 mg/m2 yrだった。アイスコアおよび札幌の積雪中に含まれる鉄の溶解度はそれぞれ10%,1.2%だった。
  • Snow hydrological study on snowmelt flood during the rain-on-snow event (2) — Rain simulation experiment over the snow surface —               
    石井 吉之, 中坪 俊一, 森 章一, 的場 澄人, 兒玉 裕二
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2011, Japanese, Poster presentation
    [Domestic Conference]
  • Stable Isotopes and Chemical Composition of a shallow ice core of the Fedchenko Glacier, Pamirs               
    雨宮 俊, 竹内 望, 藤田 耕史, 的場 澄人, 岡本 祥子, Podolskiy Evgeny, Bodington Dylan, Vladimir Aizen
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2011, Japanese, Poster presentation
    [Domestic Conference]
  • Concentration of iron solved from atmospheric dust particle in precipitation ̶ Solubility test of atmospheric iron using ice core and snow cover ̶               
    佐々木 央岳, 的場 澄人, 中村 一樹, 佐藤 和秀, 白岩 孝行
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2011, Japanese, Oral presentation
    [Domestic Conference]
  • Long-term variations of chemical signals in the Aurora Peak Ice-core from Alaska               
    Matoba, S, A. Tsushima, H. Sasaki, T. Shiraiwa, K. Yoshikawa
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2011, Japanese, Oral presentation
    [Domestic Conference]
  • Borehole measurement of deep ice coring site at Dome Fuji, Antarctica and characteristics of ice sheet near bedrock               
    本山秀明, 新堀邦夫, 倉元隆之, 飯塚芳徳, 三宅隆之, 平林幹啓, 的場澄人
    JSSI and JSSE Joint Conference on Snow and Ice Research, 2011, Japanese, Poster presentation
    [Domestic Conference]
  • Field science with a polar explorer               
    Matoba, S, T. Yamasaki
    Japan Geoscience Union Meeting, 2011, Japanese, Oral presentation
    [Domestic Conference]
  • Reconstruction of summer temperature by Aurora Peak ice core, Alaska Range               
    岡本祥子, 對馬あかね, 佐々木央岳, 的場澄人, 白岩孝行
    Japan Geoscience Union Meeting, 2011, Japanese, Oral presentation
    [Domestic Conference]
  • A 274-year environmental record of from Aurora Peak ice core, Alaska.               
    對馬あかね, 的場澄人, 福田武博, 杉山慎, 吉川謙二, 白岩孝行
    Japan Geoscience Union Meeting, 2011, Japanese, Oral presentation
    [Domestic Conference]
  • Characteristics of Isotope and Chemical Composition in the Fedchenko Glacier, Pamirs               
    雨宮俊, 竹内望, 藤田耕史, 的場澄人, 岡本祥子, Podolskiy Evgeny
    Japan Geoscience Union Meeting, 2011, Japanese, Oral presentation
    [Domestic Conference]
  • Is the source of iron River Amur or Asian Dust? -Estimation of air-borne Fe flux from ice core               
    Matoba, S, H. Sasaki, T. Shiraiwa
    Japan Geoscience Union Meeting, 2011, Japanese, Invited oral presentation
    [Invited], [Domestic Conference]
  • アラスカ・オーロラピークで掘削されたアイスコア中の化学成分の解析               
    對馬あかね, 的場澄人, 岡本祥子, 佐々木央岳, 福田武博, 杉山慎, 白岩孝行, Daniel Solie, 吉川謙二
    雪氷研究大会(2010・仙台), 2010, 日本雪氷学会, Japanese, Poster presentation
    仙台, [Domestic Conference]
  • カムチャツカ・イチンスキーアイスコアのdDプロファイルとオホーツク海の海氷面積の変動               
    的場澄人, 對馬あかね, 佐々木央岳, 白岩孝行, Y. D. Muravyev
    雪氷研究大会(2010・仙台), 2010, 日本雪氷学会, Japanese, Poster presentation
    仙台, [Domestic Conference]
  • 黄砂から降水中に溶出する鉄濃度-積雪を用いた黄砂の溶解度試験-               
    的場澄人, 中村一樹, 佐藤和秀
    雪氷研究大会(2010・仙台), 2010, 日本雪氷学会, Japanese, Poster presentation
    仙台, [Domestic Conference]
  • パミール・フェドチェンコ氷河2009年アイスコアの掘削調査               
    竹内望, 藤田耕史, 的場澄人, 岡本祥子, E. Podolyskiy, D. Bodington, V. Aizen
    雪氷研究大会(2010・仙台), 2010, 日本雪氷学会, Japanese, Oral presentation
    仙台, [Domestic Conference]
  • Is atmospheric iron deposition important for primary production? Lesson from Alaskan ice core               
    Sasaki, H, Matoba, S, Shiraiwa, T, Nishioka J, Benson, C. S
    Interntional Glaciological Society, International Symposium on snow, ice and humanity in a changing climate, 2010, International Glaciological Sciety, English, Oral presentation
    Sapporo, [International presentation]
  • Seasonal variation in chemical species in the ice core drillied at Aurora Peak, Alaska               
    Tsushima A, Matoba S, Okamoto S, Sasaki H, Fukuda T, Sugiyama S. Solie D, Yoshikawa K
    Interntional Glaciological Society, International Symposium on snow, ice and humanity in a changing climate, 2010, International Glaciological Sciety, English, Poster presentation
    Sapporo, [International presentation]
  • Records of sea-ice extent and air temperature at the Sea of Okhotsk from an ice core of Mount Ichinsky, Kamchatka               
    Matoba S, Shiraiwa T, Tsushima A. Sasaki, H. Muravyev Y, D
    Interntional Glaciological Society, International Symposium on snow, ice and humanity in a changing climate, 2010, International Glaciological Sciety, English, Oral presentation
    Sapporo, [International presentation]
  • アラスカ・オーロラピークの化学解析結果               
    對馬 あかね, 的場 澄人, 岡本 祥子, 佐々木 央岳, 福田 武博, 杉山 慎, 白岩 孝行, Dan Solie, 吉川譲二
    日本地球科学惑星連合大会, 2010, 日本地球惑星科学連合, Japanese, Oral presentation
    千葉, [Domestic Conference]
  • 50 YEARS RECORDS OF CLIMATE CHANGES AT THE SEA OF OKHOTSK EXTRACTED FROM AN ICE-CORE OF MOUNT ICHINSKY, KAMCHATKA.               
    Matoba S, Shiraiwa T, Tsushima A, Sasaki H, Muravyev Y.D
    Second international symposium on the Arctic research, 2010, National Committee of IASC, English, Oral presentation
    Tokyo, [International presentation]
  • カムチャツカ・イチンスキーアイスコアから得られた過去50年間のオホーツク海の気温と海氷の変動               
    的場澄人, 對馬あかね, 佐々木央岳, Y. D. Muravye, 白岩孝行
    平成21年度極地気水圏シンポジウム, 2009, 国立極地研究所, Japanese, Invited oral presentation
    東京, [Domestic Conference]
  • アラスカ・ランゲル山雪氷コア中の鉄濃度から推定した北部北太平洋域への鉄の沈着量               
    佐々木央岳, 的場澄人, 白岩孝行
    日本地球科学惑星連合大会, 2009, 日本地球惑星科学連合, Japanese, Oral presentation
    千葉, [Domestic Conference]
  • カムチャツカ・イチンスキーアイスコア中の化学プロファイルから得られた気候変動情報               
    的場澄人, 對馬あかね, 佐々木央岳, 白岩孝行
    日本地球科学惑星連合大会, 2009, 日本地球惑星科学連合, Japanese, Oral presentation
    千葉, [Domestic Conference]
  • 北部北太平洋域への大気由来鉄沈着量の推定 -アイスコアとエアロゾル観測からの評価-               
    的場澄人, 西岡 純, 佐々木央岳, 小埜恒夫, 南秀樹, 野村睦, 白岩孝行
    日本エアロゾル学会, 2009, 日本エアロゾル学会, Japanese, Oral presentation
    金沢, [Domestic Conference]
  • カムチャツカ・イチンスキーアイスコア中の水素安定同位体比の負のピークの解釈               
    的場澄人, 對馬あかね, 佐々木央岳, Y. D. Muravye, 白岩孝行
    雪氷研究大会(2009・札幌), 2009, 日本雪氷学会, Japanese, Poster presentation
    札幌, [Domestic Conference]
  • 流跡線解析を用いたアラスカ・ランゲル山雪氷コア中の鉄フラックスの変動評価               
    佐々木央岳, 的場澄人, 白岩孝行
    雪氷研究大会(2009・札幌), 2009, 日本雪氷学会, Japanese, Poster presentation
    札幌, [Domestic Conference]
  • アラスカ・オーロラピークの氷コア掘削地における氷河流動数値モデル               
    福田武博, 杉山慎, 白岩孝行, 的場澄人
    雪氷研究大会(2009・札幌), 2009, 日本雪氷学会, Japanese, Poster presentation
    札幌, [Domestic Conference]
  • 50-year records of climate changes in ice-cores from Kamchatka and Alaska               
    Matoba, S
    ILTS International Symposium "Frontier of Low Temperature Science", 2009, Institute of Low Temperature Science, Hokkaido University, English, Invited oral presentation
    Sapporo, [International presentation]
  • Alpine ice core drilling of Japan               
    Matoba, S
    2nd Asia Alpine Glacier Workshop, 2009, Korean Polar Reserach Insititute, English, Invited oral presentation
    Incheon, [International presentation]
  • The Sea of Okhotsk Bountiful sea nutured by sea ice               
    S. Matoba
    Winter Cities Forum, 2008, Winter City Forum, English, Invited oral presentation
    Nuuk, Greenland, [International presentation]
  • 北部北太平洋域へのエアロゾル鉄沈着量の推定 - アイスコアからの評価 -               
    佐々木央岳, 的場澄人, 西岡純, 白岩孝行
    日本海洋学会春季大会, 2008, 日本海洋学会, Japanese, Oral presentation
    東京, [Domestic Conference]
  • アラスカ・ランゲル山雪氷コア中の鉄濃度から推定した北部北太平洋への鉄の沈着量               
    佐々木央岳, 的場澄人, 白岩孝行
    雪氷研究大会(2008・東京), 2008, 日本雪氷学会, Japanese, Poster presentation
    東京, [Domestic Conference]
  • 2008年アラスカ・オーロラピークにおける氷河流動測定・氷厚探査               
    福田武博, 杉山慎, 白岩孝行, 的場澄人
    雪氷研究大会(2008・東京), 2008, 日本雪氷学会, Japanese, Poster presentation
    東京, [Domestic Conference]
  • アラスカ山脈オーロラピーク雪氷コアの現場解析               
    佐々木央岳, 岡本祥子, 白岩孝行, 的場澄人, 杉山慎, 福田武博, Solie Daniel, 吉川謙二, Benson Carl
    雪氷研究大会(2008・東京), 2008, 日本雪氷学会, Japanese, Poster presentation
    東京, [Domestic Conference]
  • アラスカ山脈尾ローラピークにおける雪氷コア掘削概方               
    白岩孝行, 的場澄人, 杉山慎, 佐々木央岳, 岡本祥子, 福田武博, Solie Daniel, 吉川謙二, Benson Carl
    雪氷研究大会(2008・東京), 2008, 日本雪氷学会, Japanese, Poster presentation
    東京, [Domestic Conference]
  • ロシア・カムチャツカ州・イチンスキー氷河コアの化学解析               
    的場澄人, 佐々木央岳, 白岩孝行, Muravyev Yalroslav
    雪氷研究大会(2008・東京), 2008, 日本雪氷学会, Japanese, Poster presentation
    東京, [Domestic Conference]
  • アラスカ・ランゲル山雪氷コア中の鉄濃度から推定して北部北太平洋への鉄の沈着量               
    佐々木央岳, 的場澄人, 白岩孝行
    平成20年度極域気水圏・生物圏合同シンポジウム, 2008, 国立極地研究所, Japanese, Oral presentation
    東京, [Domestic Conference]
  • ロシア・カムチャツカ州・イチンスキー氷河コアのプロファイル               
    的場澄人, 佐々木央岳, 白岩孝行, Muravyev Yalroslav
    平成20年度極域気水圏・生物圏合同シンポジウム, 2008, 国立極地研究所, Japanese, Oral presentation
    東京, [Domestic Conference]
  • 子ども達の雪氷防災意識向上を継続的に支える試み               
    中村 一樹, 三好 真紀, 久保田 敬二, 石本 敬志, 的場 澄人, 金森 晶作, 樋口 和生
    日本雪氷学会全国大会, 2007, 日本雪氷学会, Japanese, Invited oral presentation
    富山, [Domestic Conference]
  • アラスカ、ランゲル山コアの精密密度による古環境復元               
    金森 晶作, 白岩 孝行, 的場 澄人, 安成 哲平
    日本雪氷学会全国大会, 2007, 日本雪氷学会, Japanese, Invited oral presentation
    富山, [Domestic Conference]
  • アラスカ・ランゲル山コア中の鉄濃度の変動               
    佐々木央岳, 的場澄人, 白岩孝行
    第30回極域気水圏シンポジウム, 2007, 国立極地研究所, Japanese, Invited oral presentation
    東京, [Domestic Conference]
  • アラスカ・ランゲル山雪氷コア中の鉄濃度の変動               
    佐々木央岳, 的場澄人, 白岩孝行
    日本雪氷学会全国大会, 2007, 日本雪氷学会, Japanese, Invited oral presentation
    秋田, [Domestic Conference]
  • 氷河観測における日本から送られる気象情報の取得方法               
    的場澄人, 中村一樹, 樋口和生
    日本雪氷学会北海道支部研究発表会, 2007, 日本雪氷学会, Japanese, Invited oral presentation
    富山, [Domestic Conference]
  • ロシアカムチャツカ・イチンスキー氷河観測報告               
    的場澄人, Ushakov, S. V, 新堀邦夫, 樋口和生, 佐々木央岳, 山崎哲秀, Ovshannikov, A. A, Manevich, A. G, Zhideleeva, T. M, Kutuzov, S, Muravyev, Y. D, 白岩孝行
    日本雪氷学会全国大会, 2007, 日本雪氷学会, Japanese, Poster presentation
    富山, [Domestic Conference]
  • 中国・祁連山脈・七一氷河における表面氷の化学組成               
    三宅 隆之, 植竹 淳, 的場 澄人, 坂井 亜規子, 藤田 耕史, 藤井 理行, 姚 檀棟, 中尾 正義
    日本雪氷学会全国大会, 2006, 日本雪氷学会, Japanese, Poster presentation
    秋田, [Domestic Conference]
  • アラスカ・ランゲル山雪氷コアの酸素・水素同位体比               
    戸井田 武, 白岩 孝行, 的場 澄人
    日本雪氷学会全国大会, 2006, 日本雪氷学会, Japanese, Poster presentation
    秋田, [Domestic Conference]
  • カムチャツカ半島、ウシュコフスキー山アイスコアの水素同位体比から復元される過去2世紀超の気候記録               
    佐藤 建, 白岩 孝行, 的場 澄人
    日本雪氷学会全国大会, 2006, 日本雪氷学会, Japanese, Poster presentation
    秋田, [Domestic Conference]
  • アラスカ雪氷コア中の化学成分と北太平洋十年規模振動との関係               
    的場澄人, 金森晶作, Benson, C. S, 白岩孝行
    日本雪氷学会全国大会, 2006, 日本雪氷学会, Japanese, Poster presentation
    秋田, [Domestic Conference]
  • 雪氷コアによる北部北太平洋の数十年周期気候・大気環境変動の復元               
    白岩 孝行, 東 久美子, 的場 澄人, 金森 晶作, 安成 哲平
    日本雪氷学会全国大会, 2005, 日本雪氷学会, Japanese, Poster presentation
    秋田, [Domestic Conference]
  • 2005年アラスカ、ランゲル山における氷河観測               
    的場澄人, 金森晶作, Benson, C. B, Luethi, M. P, Solie, D, Arendt, A, 白岩孝行
    日本雪氷学会全国大会, 2005, 日本雪氷学会, Japanese, Poster presentation
    秋田, [Domestic Conference]
  • 古気候の世界-氷河から環境をよみとく?               
    的場澄人
    第25会寒地技術シンポジウム, 寒地技術センター, Japanese, Keynote oral presentation
    札幌, [Domestic Conference]

Courses

  • 地球雪氷学基礎論               
    北海道大学大学院
  • 地球雪氷学実習               
    北海道大学大学院
  • 古環境学基礎論               
    北海道大学大学院
  • 氷河氷床学特論               
    北海道大学大学院
  • フィールド体験学習               
    北海道大学
  • 寒冷圏生活文化               
    藤女子大学
  • 科学と現代               
    北海道教育大学
  • 南極学基礎論               
    北海道大学

Affiliated academic society

  • 日本地球惑星科学連合               
  • 国際雪氷学会(International Glaciological Society)               
  • 日本雪氷学会               
  • 日本エアロゾル学会               
  • Japan Geoscience Union               
  • Internatinal Glaciological Society               

Works

  • グリーンランド氷床雪氷調査(SIGMA)               
    2011
  • クロモフ号によるオホーツク海およびブッソル海峡の海洋観測               
    2010
  • レゾリュート沖での海氷表面霜の観測               
    2010
  • カムチャツカ・イチンスキーアイスコアから得られた 過去50年間のオホーツク海の気温と海氷の変動               
    2009
  • カムチャツカ・イチンスキーアイスコア中の負のδDのピークの解釈               
    2009
  • 北部北太平洋域への大気由来鉄沈着量の推定 -アイスコアとエアロゾル観測からの評価-               
    2009
  • フェドチェンコ氷河観測               
    2009
  • Singals of climate changes in an ice-core obtained from Mount Ichinsky, Kamchatka               
    2009
  • ロシア・カムチャツカ州・イチンスキー氷河コアのプロファイル               
    2008
  • ロシア・カムチャツカ州・イチンスキー氷河コアの化学解析               
    2008
  • アラスカ・オーロラピーク氷河調査               
    2008
  • 北部北太平洋域へのエアロゾル鉄沈着量の推定 -アイスコアからの評価-               
    2008
  • ロシアカムチャツカ・イチンスキー氷河観測報告               
    2007
  • 氷河観測における日本から送られる気象情報の取得方法               
    2007
  • アラスカ雪氷コア中の化学成分と北太平洋十年規模振動との関係               
    2006
  • カムチャツカ・イチンスキー山氷河掘削               
    2006
  • Ice-core drilling at Mt. Ichinsky, Kamchatka               
    2006

Research Themes

  • 氷河流動による長期物質循環と雪氷微生物の氷河暗色化過程の解明
    科学研究費助成事業
    Apr. 2024 - Mar. 2029
    竹内 望, 杉山慎, 島田利元, 的場澄人, 永塚尚子, 大沼友貴彦, 植竹淳, 藤田耕史, 瀬川高弘
    日本学術振興会, 基盤研究(A), 千葉大学, Competitive research funding, 24H00260
  • Investigation of the Impact on Climate Change via a 4-Dimensional Assessment of Material Circulation and Atmospheric Oxidation Capacity in the Antarctic Troposphere
    Grants-in-Aid for Scientific Research
    01 Apr. 2024 - 31 Mar. 2028
    原 圭一郎, 平林 幹啓, 高島 久洋, 的場 澄人, 飯塚 芳徳, 須藤 健悟, 竹中 規訓, 石野 咲子, 矢吹 正教
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Fukuoka University, 24H00757
  • Hazard Map based on Numerical snow Avalanche model and Spatio-temporal variation of snow
    Grants-in-Aid for Scientific Research
    05 Apr. 2021 - 31 Mar. 2026
    山口 悟, 西村 浩一, 的場 澄人, 大風 翼, 西森 拓, 伊藤 陽一, 新屋 啓文, 常松 佳恵
    風砕や風速変動による積雪構造の時空間的な非一様性のモデル化に関しては, 低温室実験を実施し,風上からの雪粒子の供給と風速に応じて雪面の削剥が起こり,雪紋のような風向に垂直な波状のパターンではなく,風向方向に削剥されたパターンが生じることがわかった. また冬季にニセコの山の尾根周辺に風速計やLiDARを設置し,実際に吹雪が発生して積雪が再配分されている最中の観測を実施し,風速が変動する状況や雪庇が発達する様子を捕えることに成功した.さらに北海道東部の開けた雪原において,吹雪のタワー観測を行い,風速変動に伴う飛雪流量の最大値の評価について検討をするとともに,十分な雪の吹きだまりが形成された状態における吹きだまり内部の積雪密度の分布を取得した.
    積雪構造の時空間的な非一様性をフィールドで簡易に測定できる装置の開発に関しては,軽量化にむけた装置の基本設計を引き続き進めるとともに,2021年度に作成した積雪の誘電率を測定することで含水状態を測定する試作機に関して,精度検証のための低温室実験を実施した.
    予測誤差を考慮した情報発信技術の開発に関しては,本研究で使用するPCQ法において不確定性のある変数が一つの場合(一変数)に対する確率論的ハザードマップ作成手法を確立した.
    システムの実用化にむけたスキー場の協力を得た社会実装実験では,2021年度に実施した航空レーザ測量によるニセコアンヌプリ山域全体の積雪深分布およびオルソ画像を,スキー場関係者に公開した.これらはGISソフトを使用することで関係者が自由に拡大縮小して現場の状況を確認することができるため,好意的な反応が得られた.このほか,人工雪崩実験の代わりにスキー場の協力を得て吹雪時に雪庇が発達している最中とその前後に積雪観測を行い,雪庇が不安定な状態から安定化する様子を観測した.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), National Research Institute for Earth Science and Disaster Prevention, 21H04601
  • 北極季節海氷域での海塩組成分別とエアロゾル放出過程のパラメタリゼーション
    科学研究費助成事業
    Jun. 2023 - Mar. 2026
    原 圭一郎, 平林 幹啓, 的場 澄人
    日本学術振興会, 挑戦的研究(萌芽), 福岡大学, 23K18525
  • Quantitative evaluation of the three major light-absorbing impurities accelerating glacier ablation
    Grants-in-Aid for Scientific Research
    01 Apr. 2020 - 31 Mar. 2025
    坂井 亜規子, 竹内 望, 青木 輝夫, 的場 澄人, 松井 仁志, 大畑 祥
    世界の山岳氷河は温暖化により近年縮小傾向にあり、特にアジア高山域では水資源としての役割を持つ氷河の将来予測に注目が集まっている。本研究は氷河の表面の不純物が日射の吸収率(アルベド)、ひいては氷河の質量収支変動に及ぼす影響を明らかにするという課題である。
    現地観測を行うことができなかったため、研究対象とするモンゴル西部の氷河について気象データや衛星画像から氷河表面の日射吸収率の変動と気温や降水量の変動を解析し、氷河の質量収支変動と比較して解析を行った。この結果氷河の質量収支は2000年から減少し続けているが、その減少速度は2010年以降2020年までは2000-2010年と比較すると約半分になっており、減少速度が低下している。この原因として気温の低下、降水量の増加、アルベドの上昇の3つの可能性が挙げられるが、解析の結果、気温は2000-2020年にかけて特に増減の傾向は無く、夏季を除く降水量の増加とアルベドの上昇が原因であることがわかった。このように、氷河の変動と気象要素を丁寧に解析を行うと、気温変動によって氷河の質量収支は変動しているわけではなく、降水量や降雪に伴うアルベドの変化により、氷河の質量が変動していることがわかった。
    また、過去の観測データの解析により、氷河消耗域の裸氷帯のアルベドには光吸収性不純物の量だけでなく、氷自体の変化、氷が日射の透過吸収によって融解し形成される風化氷も重要であることが明らかとなってきた。
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Nagoya University, 20H00196
  • Development of an advanced method for monitoring the Arctic environments using GCOM-C/SGLI and the in-situ data collection and the collaboration with a numerical climate model for enhancing the value of the SGLI cryosphere products               
    第3回地球観測研究
    Apr. 2022 - Mar. 2025
    Hori M, K. Sugiura, T. Aoki, T. Tanikawa, M. Niwano, A. Hachikubo, S. Matoba
    JAXA, JX-PSPC-550434
  • Arctic Challenge for Sustainability II
    環境技術等研究開発推進事業費補助金事業
    Jun. 2020 - Mar. 2025
    Coinvestigator
  • 世界一の確度をもつ過去200年間の沈着エアロゾルのデータベース創成と変遷解明
    科学研究費助成事業 基盤研究(S)
    Jun. 2020 - Mar. 2023
    飯塚芳徳
    日本学術振興会, Competitive research funding
  • 次世代積雪物理量測定技術開発と精密積雪物理モデルに基づく雪氷圏変動監視手法の確立               
    科学研究費補助金 基盤研究(A)
    Apr. 2015 - Mar. 2021
    山口悟
    日本学術振興会, Competitive research funding
  • Freshwater discharge from the Kamchatka Peninsula controls Pan-Okhotsk land-ocean linkage system
    Grants-in-Aid for Scientific Research
    Apr. 2017 - 31 Mar. 2020
    Mitsudera Humio
    Oyashio is one of most highly productive ocean in the world. This is owing to the Pan-Okhotsk land-ocean linkage system that provides the Oyashio with iron, an essential micronutrient, originating in wetlands in the Amur River basin via intermediate-layer circulation in the Sea of Okhotsk. This project aimed to elucidate roles of precipitation, snow and glacier over the Kamchatka Peninsula, which transfers information of atmospheric variations to the ocean through riverine discharge. We hypothesized that the riverine discharage from the peninsula may control the Pan-Okhotsk land-ocean linkage system. We have found that (1) the total amount of discharge from the Kamchatka Peninsula is approximately 80% of that of the Amur River, and (2) freshwater from the Kamchatka Peninsula gives more impacts on salinity of the dense shelf water that drives the intermediate-layer circulation than that from the Amur River does.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, Competitive research funding, 17H01156
  • Recent surface darkening and abrupt melting of Greenland ice sheet (SIGMA2)
    Grants-in-Aid for Scientific Research
    Apr. 2016 - 31 Mar. 2020
    Aoki Teruo
    In order to clarify the recent surface melting of the Greenland ice sheet, in-situ field observations, satellite remote sensing and numerical modelling were conducted. In the field observations, existing automatic weather station observations were continued and the data were published. Ice core samples were analyzed to characterize water vapor and mineral dust transport. In satellite remote sensing, we developed an algorithm to retrieve the snow and ice physical parameters using a non-spherical snow particle shape model and quantified the causes of ice sheet surface darkening. In numerical modelling, a regional meteorological model including the detailed processes of light-absorbing aerosols (LAA) was developed. A regional meteorological model including snow metamorphism was used to simulate the time and spatial variation of ice sheet surface melting. In addition, the radiative forcing due to LAA in the atmosphere and snow/ice was estimated by an earth system model.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Competitive research funding, 16H01772
  • グリーンランド氷床コアに含まれる水溶性エアロゾルを用いた人為的気温変動の解読
    科学研究費補助金 基盤研究(A)
    Apr. 2014 - Mar. 2019
    飯塚芳徳
    日本学術振興会, Competitive research funding
  • Frost flowers and sea-salt aerosols over seasonal sea-ice areas in north-western Greenland during winter-spring
    Grants-in-Aid for Scientific Research
    01 Apr. 2013 - 31 Mar. 2017
    HARA Keiichiro, HIRABAYSHI Motohiro, YAMSAKI Tetsuhide
    Simultaneous observations of frost flowers, brine, and aerosol particles were conducted around Siorapaluk in northwestern Greenland. Water-soluble frost flower and brine constituents are sea salt constituents. Concentration factors of sea-salts of frost flowers and brine relative to seawater were 1.14 - 3.67. Sea-salt enrichment of Mg2+, K+, Ca2+, and halogens in frost flowers related to associated with sea-salt fractionation. High aerosol number concentrations correspond to higher abundance of sea-salt particles in both coarse and fine modes, and blowing snow and strong winds. Coarse and fine sea-salt particles were found to be rich in Mg. Strong Mg enrichment might be more likely to proceed in fine sea-salt particles. Mg-rich sea-salt particles might be released from the surface of snow and slush layer on sea-ice and frost flowers. Mirabilite-like and ikaite-like particles were identified only near new sea-ice areas. We propose and describe sea-salt cycles in seasonal sea-ice areas.
    Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Exploratory Research, Fukuoka University, 25550018
  • 山岳氷河アイスコア解析による北太平洋地域における小氷期以降の気候・環境変動復元
    科学研究費補助金 基盤研究(C)
    Apr. 2014 - Mar. 2017
    的場澄人
    日本学術振興会, Principal investigator, Competitive research funding
  • Effects of snow impurities and glacial microbes on abrupt warming in the Arctic
    Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)
    01 Apr. 2011 - 31 Mar. 2016
    Aoki Teruo, MOTOYAMA Hideaki, TAKEUCHI Nozomu, MATOBA Sumito, HORI Masahiro, HACHIKUBO Akihiro, YAMAGUCHI Satoru, TANAKA Yasumichi, IWATA Yukiyoshi, SUGIURA Konosuke, KODAMA Yuji, FUJITA Koji, KUCHIKI Katsuyuki, NIWANO Masashi, HOSAKA Masahiro, HASHIMOTO Akihiro, TANIKAWA Tomonori, TANAKA Yasumichi, UETAKE Jun, NAGATSUKA Naoko, SUGIYAMA Shin, MOTOYOSHI Hiroki, SHIMODA Seiji, MOTOYA Ken
    From field observations on Greenland ice sheet, it was found that the contribution to albedo reduction in accumulation area by snow impurities such as black carbon (BC) is smaller than that by snow grain growth. Drastic surface melting event in July 2012 was accelerated by downward longwave radiation from low cloud. In ablation area, glacial microbes were contained in surface impurities and could contribute to the albedo reduction remarkably. Satellite remote sensing confirmed that the cause of darkening of ice sheet surface after 2000 is snow grain growth in accumulation area and the expansions of bare ice and dark area including glacial microbes in ablation area. We drilled a 223 m ice core in northwest Greenland ice sheet and analyzed the BC concentrations since 1660, which has a peak around 1920-1930 several times higher than the present value.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (S), Japan, Meteorological Research Institute, 23221004
  • 北極域における積雪汚染及び雪氷微生物が急激な温暖化に及ぼす影響評価に関する研究
    科学研究費補助金 基盤研究(S)
    Apr. 2011 - Mar. 2016
    青木輝夫
    日本学術振興会, 基盤研究(A), 気象庁気象研究所, Competitive research funding, 23241011
  • Elucidation of thermohaline/biogeochemical circulation systems connecting the Sea of Okhotsk with subarctic North Pacific Ocean
    Grants-in-Aid for Scientific Research
    01 Apr. 2010 - 31 Mar. 2015
    WAKATSUCHI Masaaki, MITSUDERA Humio, NISHIOKA Jun, NAKAMURA Tomohiro, EBUCHI Naoto, WATANABE Yutaka, SUZUKI Koji, KURODA Hiroshi, OHSHIMA Keiichiro, TSUMUNE Daisuke, MATOBA Sumito
    We investigated the thermohaline/biogeochemical circulation systems, connecting the Sea of Okhotsk with the North Pacific, to elucidate a ‘miraculous mechanism’ that supports abundant fisheries resources in the Okhotsk and Oyashio regions. Salinity of the dense shelf water (DSW) over the northern shelf of the Okhotsk Sea controls the strength of the thermohaline circulation of the North Pacific Ocean. DSW salinity is determined by relative contribution among the salinity anomaly that propagates long distance from the subarctic gyre, freshwater anomaly by precipitation, and saline water anomaly rejected during sea ice formation. DSW entrains nutrients such as iron, originating in the Amur River and deposited over the continental shelf, and spreads these materials to the North Pacific Ocean. This study has revealed an exquisite thermohaline-biogeochemical system coupled through DSW and tidal mixing, which controls primary production in the large area of the subarctic North Pacific.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (S), Hokkaido University, 22221001
  • Development of clean technique for trace metal measurement method in the sea ice
    Grants-in-Aid for Scientific Research
    2011 - 2012
    NISHIOKA Jun, MATOBA Sumito
    We developed two clean analytical procedure for determining iron and aluminium concentrations in the sea ice. One is the method that removed contaminated outer layer of sea ice. The sea ice corer is collected by a lightweight filament tube with an aluminum cutting shoe and heat-treated steel cutting teeth. The outer layers of core were carefully removed using a ceramic knife to remove contaminated part during coring. The other method is comprised by ice meltar and in-line sampling and Fe analytical system. These method were applied to oridinary a sea ice collected from the Sea of Okhotsk.
    Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Exploratory Research, Hokkaido University, 23651001
  • 海洋表層マッピングによる親潮域の鉄供給過程の評価
    科学研究費助成事業
    2009 - 2010
    西岡 純, 小埜 恒夫, 的場 澄人
    親潮域の生物生産を支える鉄の供給過程を明らかにするために下記の研究を進めた。
    本年度は、これまでに実施してきた観測研究の結果に基づき、大気ダスト由来と海洋循環由来の鉄の供給過程が、親潮域・混合域の植物プランクトン増殖に対してどのような役割を果たしているのかについて、定量的・定性的に評価する事を試みた。また、それぞれの供給過程に関わる重要なプロセスやパラメータを抽出した。
    その結果、海洋内部の循環は、明瞭な季節的変動を駆動する供給過程であり、中層の循環によるオホーツク海からの高い鉄濃度水塊の移送、千島海峡の混合過程を介した鉄濃度の再分配、冬季の混合層発達による高鉄濃度水塊の表層への回帰などが重要なプロセスとして挙げられた。この海洋循環で供給されている鉄分は、毎年春季に起こる植物プランクトンのブルームを生み出すために利用されている。一方、大気ダスト経由の鉄は、冬季~春季にイベント的に供給されており、バックグランドにある海洋循環で決まる鉄濃度の周年変動に上乗せして、突発的に、また空間的には不均一に供給されるものであると推察された。表層鉄濃度の周年変動に影響を与えるレベルの供給量ではないが、年間に数回から十回程度、植物プランクトン増殖にインパクトを与えるレベルの鉄を供給するイベントが発生している可能性があることが分かった。以上の研究結果から、それぞれの鉄供給過程は、海洋の生物生産に対してそれぞれの役割を持ち、違った特徴の生態系の応答を導いていると考えられる。
    日本学術振興会, 特定領域研究, 北海道大学, 21014001
  • Simultaneous investigation s on acid snow in Japan
    Grants-in-Aid for Scientific Research
    2008 - 2010
    SATO KAZUHIDE, KAMEDA Takao, ISHII Yoshiyuki, MATOBA Sumito, TAKAHASHI Kazuyoshi, ISHIZAKA Masaaki, TAKEUCHI Yukari, YOKOYAMA Koutarou, KOMINAMI Yasuhiro, KAWADA Kunio, WATANABE Kouichi, IIDA Toshiaki, IGARASHI Makoto, TAKEUCHI Nozomi
    Snow samples were gathered from Hokkaido Island to Yamagata, Niigata and Toyama Prefectures in the Mainland in winter. By analyzing the chemical characteristics of these samples concerning an acid snow, the actual conditions were investigated.
    A lot of findings were obtained concerning the hydrogen peroxide concentration of snow that the reports on its concentration are very little. Some relations were seen among the air pollutant substances, the major ion concentrations, the hydrogen peroxide concentrations, the pH of snow and the snow algae, etc., and the selective elutions of the ion of snowmelt water were observed, though a further observation is necessary for the grasp of a clearer relation.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Nagaoka National College of Technology, 20310113
  • Reconstruct of depositions of terrestrial materials into the northern North Pacific by ice-core analysis
    Grants-in-Aid for Scientific Research
    2007 - 2009
    SHIRAIWA Takayuki, MATOBA Sumito, YAMATAGA Kotaro, SUGIYAMA Shin, IIZUKA Yoshinori, YOSHIKAWA Kenji, SASAKI Hirotaka, FUKUDA Takehiro, TSUSHIMA Akane
    In order to study the relationship between the North Pacific climate regime shift and ocean primary production, we analyzed iron concentrations in an ice core drilled at Aurora Peak, Alaskan Range. It was found that the averaged iron deposition was 8.8mg m^2yr^<-1> for the last 10 years, but it was 29 and 19mg m^2yr^<-1> for 2001 and 2002 when there were significant Kosa events. The results suggest that the atmospheric iron deposition to the upper 30-m mixed layer will not affect the biomass production in average but the amounts as recorded in 2001 and 2002 will be high enough to affect the ocean primary production.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Research Institute for Humanity and Nature, 19340137
  • 西部北太平洋亜寒帯域(親潮域)表層の鉄濃度の変動と大気ダスト供給量との関係
    科学研究費助成事業
    2007 - 2008
    西岡 純, 小埜 恒夫, 的場 澄人
    本研究の目的は、大気ダスト経由の鉄供給が亜寒帯域表層の鉄濃度の変動にどのように寄与しているかを定量的に評価することである。研究期間内に次のI)〜III)の項目について研究を行った。I)親潮海域の定線観測(Aライン観測)において、表層鉄濃度の季節的変動を含めた時系列観測を継続して行った。II)実海域の海表層付近の大気ダスト中に含まれる鉄量の季節的な変化を観測するとともに、海水中で大気ダストから鉄がどの程度溶出してくるかを、室内実験および船上実験において検討した。III)IIのデータおよび、季節毎の親潮海域へのダストの沈着量を、Iで得られる表層鉄濃度の季節的な変動とともに解析することで、大気ダスト経由の鉄供給が亜寒帯域表層の鉄濃度の変動にどのように寄与しているかを定量的に評価した。
    これらの内容を含む本研究の結果より、当概海域の季節的な鉄濃度の変動とダストおよび海洋内循環の供給過程の寄与が明らかになってきた。親潮域表層の鉄濃度の季節的な変動は概ね次のように説明できる。親潮域では, 冬季の鉛直混合の活発な時期に下層から表層に供給され, 春季のブルーム期にほぼ枯渇するまで減少する主要栄養塩と同様のサイクルを示す。しかし, 各観測時の測点間のばらつきは明瞭であり, 冬季に詳細なマッピングを行った結果, 鉄濃度の変化は水塊の違い(混合層の発達過程の違い)にも支配されていることが分かってきた。これらの結果は, これまで考えられてきた大気経由の鉄供給に加えて, 冬季の混合過程, 水塊の水平移動, 亜表層の鉄循環などのプロセスが海洋表層の鉄濃度の変化を引き起こす重要な要因になっていることを示している。これらの結果は, 大気から海洋表層への鉄供給を評価するためには, まず海洋循環で決まる鉄濃度のバックグランド変動を把握した上で, 大気からのシグナルを抽出することが重要であることを示している。
    日本学術振興会, 特定領域研究, 北海道大学, 19030002
  • 積雪空隙内に存在する化学成分の存在形態とその挙動に関する研究
    科学研究費助成事業
    2006 - 2007
    的場 澄人
    大気エアロゾルから積雪中の化学シグナルが形成される過程には、(1)降雪へのエアロゾルの取り込み過程、(2)積雪内での化学成分の移動と大気への放出、(3)積雪内での化学反応、(4)融雪をともなう化学成分の溶出と移動、(5)氷河流動による層序の擾乱、が挙げられる。本研究の目的は、これらの諸過程の中で(2)と(3)の過程と機構に着目し、積雪内での化学成分の挙動、存在形態を明らかにすることである。
    北海道幌加内町母子里にある当研究所融雪観測室において積雪の空隙内の存在する化学成分の挙動を調べた。積雪内に金属パイプを陥入しポンプによって空隙内の空気を吸引し,空隙内のエアロゾル成分とガス成分をフィルター上に捕集した。また同時に積雪直上の大気中のエアロゾルとガス成分をフィルター上に捕集した。捕集した成分は、イオンクロマトグラフィーで化学成分の定量を行った。
    その結果、昨年と同じように空隙内での存在が肯定的ではなかったエアロゾルが検出された。空隙内のエアロゾル濃度と大気中のエアロゾル濃度の変動は全く異なった挙動を示した。また、大気中のナトリウム濃度は10倍以上の変化を示したのに対し、空隙内のエアロゾルはほぼ一定の値を示した。このことから、空隙内から採取されたエアロゾルは、大気の影響を直接うけたものではなく、大気の変化とは独立して空隙内にエアロゾルが存在することが示唆された。また空隙内のエアロゾルは化学成分によっても挙動が異なった。これは温度や温度勾配の違いが化学成分の挙動の違いに現れたのではないかと推測される。
    以上の結果から、積雪内の化学成分挙動を明らかにする重要性が確認され、今後のアイスコアの解釈のための研究の発展が大いに期待される。
    日本学術振興会, 若手研究(B), 北海道大学, 18740289
  • Chemical features and the mechanism of the preferential elution of the major ion in acidic snow melting water by acid shock
    Grants-in-Aid for Scientific Research
    2004 - 2006
    SATOW Kazuhide, HATA Katsuji, MATOBA Sumito
    To clarify the realities of an acid snow in Japan, snow pit studies was carried out at several places in Hokkaido, and Honshu in Japan, and the snowfall sample was able to be obtained. Moreover, the precipitation once a day was gathered throughout the year at this school in Nagaoka City. Regional differences and elevation - differences could be understood in distribution of acid substances in snow and snow melting features. To search the behavior of the ion at snow-melting, the thermal analyses of the melting water of snow were done with Differential Scanning Calorimetry to analyses of the melting temperature and melting energy of uniting water and free water with different ion species and ion concentrations. The difference of flow out speed between different ion species can be seen, but also between different snows. It seems to be related to different ions and ion concentrations.
    Precipitation in winter was classified into three forms of hailstone, snow and rain, to examine the characteristic of ion concentrations by the difference of the form of precipitation. Each concentration of the major ions showed some different features.
    To examine an atmospheric chemistry system in the background of pH value in precipitation, measurements of hydrogen peroxide (H_2O_2) concentration in precipitation were carried out. H_2O_2 has a strong correlation with OH-radical that becomes the leading part of the oxidation of SO_2 and NO_2 in atmosphere. This research accomplishment was delayed because the severe earthquake attacked Chuetsu region, Niigata Prefecture, in October, 2004. However, the measurement of H_2O_2 concentration will become possible soon and some interesting results are being obtained. The H_2O_2 concentration in precipitation of winter at Nagaoka City indicated a high value in daytime. Moreover, a tendency that the H_2O_2 concentration decreases was seen as precipitation increased. Examining the relation between SO_4^<2-> and NO_3^- -H_2O_2 concentration, an especially clear correlation was not obtained though a constant tendency was seen.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Nagaoka National College of Technology, 16310129
  • RECONSTRUCTION OF CLIMATE AND ATMOSPHERIC TRANSPORT BY MEANS OF ICE CORE ANALYSES IN THE NORTH PACIFIC
    Grants-in-Aid for Scientific Research
    2004 - 2005
    SHIRAIWA Takayuki, NAKATSUKA Takeshi, TACHIBANA Yoshihiro, YAMAGATA Kotaro, MATOBA Sumito
    We analyzed the ice core drilled at Mt.Wrangell in 2004. The analyses were made for the upper 100m of the 217-m long ice core. They are hydrogen isotope ratio (0-50m), major ions (0-50m), dust concentration (0-80m), X-ray density (0-100m) and tritium (0-50m). Trace elements were also measured for the Mt.Logan ice core which we drilled in 2002. Following results are obtained by this research project :
    1.Clear seasonal cycles are found for the upper 50m of the ice core in the cases of hydrogen isotope ratio, dust and tritium concentrations. The peaks appeared in summer for delta D and spring for the dust and tritium concentrations.
    2.Standard deviation in the X-ray density variations are negatively related with delta D suggesting that the high density variations occur in spring-summer period when snow falls rather intermittently.
    3.Concentration in dust becomes higher in spring and lower in the other periods. It is also found that the dust concentration has been increasing since 2000, which coincides with observation of dust falls in Japan.
    4.Tritium concentration in the Wrangell ice core shows a beautiful seasonal cycle having the highest peak in spring. This is due to the so-called "Stratosphere-Troposphere Exchange" in air mass and the concentration can be a promising indication of atmospheric disturbances in spring.
    5.Sodium flux is positively correlated with Pacific Decadal Oscillations suggesting the atmospheric-oceanic interaction in the North Pacific.
    6.Annual Iron fluxes during the period 1980-2000 in the Logan ice core were varying from several μg/square m to 80μg/square m. The source of the iron can be ascribed to Asian dust and the nearby volcanoes.
    7.Annual accumulation rates both in the Wrangell ice core and the Logan ice core showed clear negative relationship for the last 100 years, suggesting that the PDO has impacted mountain precipitation significantly.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), 16403005
  • 親潮域へ沈着する大気ダストの生物生産への影響評価               
    科学研究費補助金
    2005
    日本学術振興会, Competitive research funding
  • Studies on long-range tansport and deposiltion processes of ail Pllutants using ice cores
    Grants-in-Aid for Scientific Research
    1999 - 2001
    AZUMA Kumiko, MATOBA Sumito, MATOYAMA Hideaki, FUJII Yoshiyuki
    Ice core studies have shown that sulfate and nitrate concentrations in Arctic snow have increased significantly since the end of the 19th century due to the influx of anthropogenic pollutants transported from industrialized regions. Trends of increasing sulfate and nitrate concentrations in snow are evident in all the ice core data from Greenland, the Canadian Arctic, and Svalbard. Temporal patterns, however, show spatial variation. The difference between the magnitude and timing of increasing trends of the sulfate ions at different Arctic sites can be attributed to their having different source regions and pathways for these pollutant ions. The pollutant sources appear to be North America for south Greenland, Devon Island and Baffin Island, Eurasia, for Ellesmere Island and Svalbard, and both North America and Eurasia for central and north Greenland. An ice core from Svalbard showed significant decreases of both sulfate and nitrate concentrations since the 1970s. These decreases could be partly attributed to the strict pollution control started in the 1970s, but they are also partly due to the changes in atmospheric circulation dominated by the North Atlantic Oscillation.
    Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), National Institute of Polar Research, 11680539
  • Reconstruction of paleo climate in the North Pacific from ice-cores obtaind from Alaska and Kamchatka               
    2001
    Competitive research funding

Social Contribution Activities

  • グリーンランドの人々の暮らし               
    07 Mar. 2018
    Lecturer
    Lecture
    上札内交流館事業,上札内交流館
    雪と氷の不思議な世界,講演・体験学習会
  • International Symposium on Cryosphere and Biosphere               
    Mar. 2018
    Organizing member
    Seminar
    International Glaciological Society
  • "雪の結晶”は戻ってきますか?・・・六花型ブーメランを作って飛ばそう               
    18 Feb. 2018
    Demonstrator
    Visiting lecture
    サイエンススパークス,札幌ドーム,札幌市
    科学の祭典札幌冬の大会
  • 子育て、ライブイベントとフィールドワーク               
    26 Oct. 2017
    Lecturer, Organizing member
    Seminar
    北海道大学低温科学研究所
  • Meteorological and Glaciological Observation at Greenland Ice Sheet               
    11 Mar. 2017
    Lecturer
    Visiting lecture
    北海道札幌啓成高等学校、札幌市青少年科学館、北海道教育委員会
    北海道科学英語発表・交流会
  • 温暖化とグリーンランド氷床の変化               
    07 Nov. 2016
    Lecturer
    Science cafe
    低温科学研究所、北極地域研究センター、THE MUSIC PLANT、ArCS北極域研究推進プロジェクト
    グリーンランドをめぐる音楽・冒険・サイエンス –北極域の持続可能な未来にむけて−
  • 心ゆさぶれ!先輩ROCK YOU               
    27 Dec. 2014
    Informant
    Media report
    日本テレビ
    心ゆさぶれ!先輩ROCK YOU
  • ためしてナットク「雪と氷のふしぎ」               
    23 Sep. 2014
    Demonstrator
    Visiting lecture
    日本雪氷学会
    子どもと雪氷を楽しむ会
  • 地球温暖化とグリーンランド氷床の変化               
    06 Dec. 2013
    Lecturer
    Lecture
    朝日新聞北海道支社、北海道テレビ放送
  • 雪を知ろう:雪ってどんなもの?               
    09 Jan. 2013
    Lecturer, Demonstrator
    Festival
    大雪・富良野ルートサポートセンター
    ウィンターサーカス・雪のワークショップ
  • 子どもの北大構内かんじき散歩と雪氷の観察会               
    09 Jan. 2010
    Lecturer
    Visiting lecture
    北海道自然観察協議会
  • 世界の雪氷圏めぐりツアー               
    03 Oct. 2009
    Lecturer, Demonstrator
    Visiting lecture
    日本雪氷学会
    「雪と氷の『ふしぎ』を一緒に考えよう「雪氷楽会in SAPPORO」
  • 雪から知る地球のひみつ               
    31 Jan. 2009
    Demonstrator
    Visiting lecture
    こどもエコクラブ交流会
    雪から知る地球のひみつ
  • グリーンランドの生活               
    11 Feb. 2008
    Lecturer
    Lecture
    小樽市総合博物館
    雪に学び雪を楽しむ「雪氷楽会」in小樽市総合博物館
  • グリーンランドと地球温暖化               
    28 Jul. 2007
    Lecturer
    Lecture
    札幌国際プラザ
    グリーンランドを知るセミナー
  • 雪国の自然現象を再現する−流氷と雪結晶−               
    30 Jul. 2006
    Demonstrator
    Festival
    青少年のための科学の祭典2006年全国大会
  • 雪から学ぶわくわく体験『雪氷楽会』in北大               
    14 Jan. 2006
    Planner, Organizing member, Demonstrator
    Science cafe
    雪氷楽会in北大

Media Coverage

  • あす『雪と氷』体験学習会、中札内JAXA研究者ら講師               
    08 Mar. 2018
    十勝毎日新聞
    十勝毎日新聞
    [Paper]
  • 三都市積雪データ公開へ               
    24 Mar. 2017
    朝日新聞
    朝日新聞北海道版
    [Paper]
  • Bulletin of Glaciological Research編集委員               
    2016
    [Pr]
  • グリーンランドで先住民族伝統の犬ぞりが活躍 氷の結晶『フロストフラワーを探しに』               
    12 May 2015
    朝日新聞
    [Paper]
  • 北極は『地球の窓』               
    01 Jan. 2015
    岩手日日新聞、夕刊デイリー、釧路新聞、陸奥新報、中國新聞、長野日報、苫小牧民報
    [Paper]
  • 「雪氷」編集委員               
    2015
    日本雪氷学会
    [Pr]
  • 伝説の犬ぞり北極快走 研究者乗せ薄い海氷で活躍               
    12 May 2014
    朝日新聞夕刊
    [Paper]
  • 氷の華み〜つけた               
    01 May 2014
    朝日小学生新聞
    [Paper]
  • 厳冬グリーンランドに“幻の氷の華”を見た               
    30 Mar. 2014
    BS朝日
    いま世界は
    [Media report]
  • 北海道宝島2014・フロストフラワー               
    02 Feb. 2014
    FM北海道
    北海道宝島2014
    [Media report]
  • 12月6日ポプラ広場「グリーンランド温暖化の最前線から」開催               
    07 Nov. 2013
    朝日新聞
    [Paper]
  • たびばん・北大をディープに探索               
    23 Jun. 2013
    STV
    たびばん
    [Media report]
  • 北極氷河 激流と化す               
    17 Sep. 2012
    朝日新聞
    [Paper]
  • Bulletin of Glaciological Research編集               
    2010
    日本雪氷学会
    [Pr]
  • 知識深める秋 温暖化を防ぎ動物守ろう 円山動物園で『雪氷楽会』               
    03 Oct. 2009
    北海道新聞
    [Paper]
  • オホーツク海の栄養探せ 氷河掘削 黄砂を調査 北大低温研,カムチャツカで               
    01 Apr. 2006
    北海道新聞
    [Paper]