Feasibility study of local @roduction and consumption of wood biomass by a small combined heat and power equipment　　　　　　　　　　　　　　　
OKADA Kazuya, YAMAGATA Sadamu
Journal of Natural Energy Research, Hokkaido, 16, 1, 17, 25, Jun. 2022, [Peer-reviewed]
Japanese, Scientific journal

Snow-melt experiment by the air supplied from the bottom of piled anow　　　　　　　　　　　　　　　
YAMAGATA Sadamu, Ohsawa Toshinobu, Fukazawa Tatsuya
Journal of Natural Energy Research, Hokkaido, 16, 1, 5, 15, Jun. 2022, [Peer-reviewed], [Lead author]
Japanese, Scientific journal

北海道における木質バイオマス利用　　　　　　　　　　　　　　　
山形 定
北海道における脱炭素社会に向けた取組み, Dec. 2021, [Invited], [Lead author]
Japanese, In book

The Potential of Snow and Ice Cold Heat Utilization in Hokkaido　　　　　　　　　　　　　　　
YAMAGATA Sadamu
JUMIN TO JICHI MONTHLY, 699, 20, 22, Jul. 2021, [Invited], [Lead author]
Japanese, In book

Installation and trial operation of an snow-melting system using air warmed by a wood stove at a snow falling area from roof　　　　　　　　　　　　　　　
YAMAGATA Sadamu, OHSAWA Toshinobu, YONETA Naoji, TATEKURA Yuhki, KOBAYASHI Yukai
Journal of Natural Energy Research, Hokkaido, 15, 1, 15, 24, Jun. 2021, [Peer-reviewed], [Lead author]
Japanese, Scientific journal

Deforestation monitoring using publicly available satellite loading SAR images　　　　　　　　　　　　　　　
YAMAGATA Sadamu, GAMOU Masahiro
Journal of Natural Energy Research, Hokkaido, 15, 1, 7, 14, Jun. 2021, [Peer-reviewed], [Lead author]
Japanese, Scientific journal

Winter asparagus production with hot water heated by pellets boiler
H. Araki, H. Nakano, S. Ichikawa, T. Kawai, T. Jishi, S. Yamagata, M. Kamide
Acta Horticulturae, 1301, 117, 122, International Society for Horticultural Science (ISHS), Dec. 2020, [Peer-reviewed]
English, Scientific journal

Disclosure necessity in public utility services of electric power: Lwssons from blackout and questionnaire survey　　　　　　　　　　　　　　　
YAMAGATA Sadamu
Journal of Natural Energy Research, Hokkaido, 14, 1, 9, 22, May 2020, [Peer-reviewed], [Lead author, Corresponding author]
Japanese, Scientific journal

Learning from Japan's First Blackout:Examining the OCCTO review process from the viewpoint of "Shippai Gaku"(failure studies)　　　　　　　　　　　　　　　
Sadamu Yamagata
Journal of Natural Energy Research, Hokkaido, 13, 1, 5, 16, Jun. 2019, [Peer-reviewed]
Japanese, Scientific journal

Emission and Cost Analysis in Asparagus Fusekomi Forcing Culture with Wood Pellet Boiler　　　　　　　　　　　　　　　
Z.Jie, T.Kumano, M.Fujii, S.Yamagata, M.Kamide, H.Araki
Japanese journal of farm work research, 54, 1, 3, 13, Mar. 2019, [Peer-reviewed]
English, Scientific journal

Economical effect of alog-boiler introduction using wood biomass from municipal forest in Shimukappu village　　　　　　　　　　　　　　　
Sadamu Yamagata
Journal of Natural Energy Research, Hokkaido, 12, 1, 5, 16, Jul. 2018, [Peer-reviewed]
Japanese, Scientific journal

Culture bed heating comparison between electric wire and hot water generated from pellet boiler in asparagus forcing production　　　　　　　　　　　　　　　
Zeng J, T. Kumano, S. Yamagata, M. Kamide, M. Fujii, H. Araki
Acta Horticulturae, 1208, 265, 270, 2018, [Peer-reviewed]
English, International conference proceedings

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.

北海道における木質バイオマス利用の現状と課題　　　　　　　　　　　　　　　
山形定
電気設備学会誌, 36, 791, 797, Nov. 2016, [Invited]
Japanese, Scientific journal

自然エネルギー利用の現状と課題－木質バイオマス利用と競合するおが粉製造業から考える－　　　　　　　　　　　　　　　
山形定
酪農ジャーナル, 69, 3, Mar. 2016, [Invited]
Japanese

Corrigendum: "The GOddard SnoW impurity module (GOSWIM) for the NASA GEOS-5 earth system model: Preliminary comparisons with observations in Sapporo, Japan" [SOLA, 10, (2014) 50-56] DOI:10.2151/sola.2014-011
Teppei J. Yasunari, K. M. Lau, Sarith P.P. Mahanama, Peter R. Colarco, Arlindo M. Da Silva, Teruo Aoki, Kazuma Aoki, Naoto Murao, Sadamu Yamagata, Yuji Kodama
Scientific Online Letters on the Atmosphere, 12, 1, c1, Meteorological Society of Japan, 2016, [Peer-reviewed]
English, Scientific journal

Contribution of urban and transboundary air pollution to PM2.5 concentrations in Sapporo
BANNAI Toshiaki, MURAO Naoto, YAMAGATA Sadamu, YAMAGUCHI Takashi, FUKASAWA Tatsuya
Journal of Japan Society of Civil Engineers, Ser. G (Environmental Research), 71, 5, 227, 233, Japan Society of Civil Engineers, Sep. 2015, [Peer-reviewed]
Japanese, Scientific journal, Elevated particulate matter (PM) concentrations in urban atmosphere in Japan are associated with fine particles emitted and/or formed in an urban area and those transported from the Asian continents. It is thus important to know each contribution for the improvement of urban PM pollution. In this study, a new approach to evaluate transboundary PM pollution is developed based on the measurement of optical properties of fine particles such as SSA (Single Scattering Albedo) and B/N ratio (absorption coefficient/fine particle number concentration), and applied to Sapporo, Japan. The results suggest that during the observation period (June - Dec. 2014), transboundary pollution contributed more than 70% to the PM concentrations in Sapporo, and that transboundary pollution contribution has a seasonal variation with a decrease in summer and an increase in autumn. The approach is expected to serve as an important tool towards effective measures for PM pollution control in Japan.

Foliar rinse study of atmospheric black carbon deposition to leaves of konara oak (Quercus serrata) standse
Hiroshi Hara, Takumi Kashiwakura, Kyo Kitayama, Sonoko Deothea Bellingrath-Kimura, Tomohiro Yoshida, Masao Takayanagi, Sadamu Yamagata, Naoto Murao, Hiroshi Okouchi, Hiroko Ogata
ATMOSPHERIC ENVIRONMENT, 97, 511, 518, PERGAMON-ELSEVIER SCIENCE LTD, Nov. 2014, [Peer-reviewed]
English, Scientific journal, Dry deposition of Black Carbon (BC) to the actual leaves of konara oak (Quercus serrata) was evaluated in a foliar rinse method in an experimental forest in the suburbs of Tokyo, Japan in order to explore deposition levels and vertical profile within the forest. At three heights of the forest of 20 m height, 20 m, 15 m, and 6 m or 4 m, leaves were sampled on a weekly basis for a couple of months in 2011 and 2012 and subjected to rinsing with water and chloroform. The BC in the rinse solution was collected on a quartz fiber filter and determined by spectrophotometry. The BC mass deposited to leaves increased with height and this profile pattern was generally maintained in the study period. The specific BC mass deposited to leaves showed considerable fluctuations with time, but the deposited BC increased rapidly with time in the bud flushing stage, then attained to a plateau, and began to decrease as the defoliation advanced. The plateau is a result of a simple accumulation with time and occasional removal due to rainfall and strong winds. The maximum BC mass deposited to leaves per leaf surface unit area occurred in June where the level was 10-15 mg-BC m(-2). The rate of BC mass deposited to leaves at the time of leaves growing was determined to be 0.237 and 0.277 mg-BC m(-2) day(-1) for measurements in 2011 and 2012, respectively. On the basis of the observed BC mass deposited to the leaves, BC mass deposited to leaves per forest floor unit area estimated with LAI showed a strong seasonality. The BC mass deposited to leaves per forest floor unit area was compared to the deposition flux from the atmosphere to the forest canopy, which would be interpreted as indicating that 30% of atmospheric BC deposition to the canopy was retained on the leaves in time of leaves growing. (C) 2014 Elsevier Ltd. All rights reserved.

The goddard snow impurity module (GOSWIM) for the NASA GEOS-5 Earth system model: Preliminary comparisons with observations in Sapporo, Japan
Teppei J. Yasunari, Teppei J. Yasunari, K. M. Lau, Sarith P, P Mahanama, Sarith P, P Mahanama, Peter R. Colarco, Arlindo M, da Silva, Teruo Aoki, Kazuma Aoki, Naoto Murao, Sadamu Yamagata, Yuji Kodama
SOLA, 10, 50, 56, Jan. 2014, [Peer-reviewed]
English, Scientific journal, The snow darkening module evaluating dust, black carbon (BC), and organic carbon (OC) depositions on the mass of snow impurities and albedo has been developed for the NASA Goddard Earth Observing System, Version 5 (GEOS-5) Earth System Model, as the GOddard SnoW Impurity Module (GOSWIM). GOSWIM consists of the updated snow albedo scheme from a previous study (Yasunari et al. 2011) and a newly developed mass concentration calculation scheme, directly using aerosol depositions from the chemical transport model (GOCART) in GEOS- 5. Compared to observations at Sapporo, the off-line simulations, forced by observation-based meteorology and aerosol depositions from GOES-5, reasonably simulated the seasonal migration of snow depth, albedos, and impurities of dust, BC, and OC in the snow surface. However, the simulated dust and BC mass concentrations in snow were especially underestimated except for the BC in the early winter, compared to the observations. Increasing the deposition rates of dust and BC could explain the observations. Removing BC deposition could possibly lead to an extension of snow cover duration in Sapporo of four days. Comparing the offline GOSWIM and the GEOS-5 global simulations, we found that determining better local precipitation and deposition rates of the aerosols are key factors in generating better GOSWIM snow darkening simulation in NASA GEOS-5.

Optical and Chemical Properties of Atmospheric Aerosols at Amami Oshima and Fukue Islands in Japan in Spring, 2001
OHTA, S, MURAO, N, YAMAGATA, S
Journal of the Meteorological Society of Japan, 91, 1, 63, 73, Meteorological Society of Japan, 2013, [Peer-reviewed]
English, Scientific journal, The optical and chemical properties of atmospheric aerosols were determined from the ground-based measurements at Amami Oshima in April 2001 during the Asian Atmospheric Particle Environmental Change Studies (APEX) campaign and at Fukue Island in March 2001. At Amami Oshima from April 10 to 16, an aerosol event was observed in which the volume scattering coefficient and sulfate concentration of fine particles increased conspicuously. At the former term of the aerosol event, the single scattering albedo reached 0.98. At the latter term of the event, on the other hand, it was 0.80-0.90 and the concentrations of elemental carbon, aluminum, and zinc increased by a factor of several to ten times compared with the rest of the observation terms. Using chemical and backward trajectory analyses, it was established that the transparent aerosols, rich in sulfate, were converted from sulfur dioxide gas emitted by the Miyake Island volcano at the former term of the aerosol event, while the turbid and absorptive aerosols were anthropogenic aerosols appearing together with Asian yellow dust from continental China at the latter term of the event. The measurements at Fukue Island showed that the volume scattering coefficients as well as the concentrations of sulfate, elemental carbon, aluminum, and zinc were higher than those at Amami Oshima, while the single scattering albedo was relatively low. This study elucidates that in spring, large amounts of anthropogenic particles are frequently transported together with Asian yellow dust from inland continental China to the Pacific Ocean, and that the single scattering albedo and the ratio of organic to elemental carbons are approximately 0.80-0.85 and 1, respectively, over the north-western Pacific Ocean.

Measurement of optical and chemical properties of atmospheric aerosols over the western Pacific Ocean　　　　　　　　　　　　　　　
Yuji Fujitani, Sachio Ohta, Tatsuo Endoh, Naoto Murao, Sadamu Yamagata
Journal of Global Environment Engineering, 8, 17, 33, Nov. 2002
English, Scientific journal, It is necessary to determine the spatial distribution and variation of optical properties and chemical species of atmospheric aerosols to estimate their direct effect on climate. In the western Pacific Ocean, where pollutants are transported from East Asia, there are few aerosol measurements available to estimate the climatic effects. In this study the optical and chemical properties of aerosols were measured on board the R/V Mirai in June-July 2000 (MR00-K04 cruise) and in May 2001 (MR01-K02 cruise) in the western Pacific Ocean during the ACE-Asia campaign. The MR00-K04 cruise covered the maritime air mass south of 30 ° N. The median volume absorption coefficient (σap) was extremely low, 1 × 10-7 m-1, and the volume scattering coefficient (σsp) ranged from 7.0 × 10-6 to 33.7 × 10-6 m-1. The single scattering albedo (ω = σsp/ (σsp + σ ap)), ranged from 0.97 to 0.99. During the MR01-K02 cruise, anthropogenic aerosols and soil particles emitted from Asian countries were detected at a distance of 500 km from the coast. In this area, the median σap was 2.2 × 10-6 m-1, 20 times higher than that measured south of 30° N in the MR00-K04 cruise. The ω values were 0.82 - 1.0 and the median of the aerosol optical thickness (AOT) at 550nm wavelength was 0.50 which was 8 times that on MR00-K04.

Concentrations of water soluble organic aerosols at mt. lemmon in arizona　　　　　　　　　　　　　　　
Masahiro Hori, Sachio Ohta, Naoto Murao, Sadamu Yamagata
Journal of Global Environment Engineering, 5, 11, 25, 1999
English, Scientific journal, Concentrations of low molecular weight dicarboxylic acids, organics and sulfate in aerosols were measured at the summit of Mt. Lemmon (2971 m), Arizona, from October 1994 to September 1996. Oxalic acid was most abundant (4.4 ~ 62.0 ng m-3) among the measured dicarboxylic acids and accounted for 50% of the total dicarboxylic acid mass concentration. Monthly mean concentrations of other dicarboxylic acid components were 0.0 ~ 11.3 ng m-3 for malonic acid, 0.6 ~ 19.9 ng m-3 for malic acid, and 0.0 ~ 5.4 ng m-3 for succinic acid together with 148.5 ~ 1015.8 ng m-3 organics and 113.9 ~ 1962.2 ng m-3 sulfate. The concentrations of these water soluble components increased from late spring to autumn, particularly in summer, as the top of the mixing layer rose above the summit of Mt. Lemmon due to the strong solar radiation. The annual time variations in dicarboxylic acid, organics and sulfate concentrations implied that the photochemical production of malic acid and malonic acid and the dissociation of organics and oxalic acid occur in the atmosphere in middle and late of summer. The concentration ratio of total dicarboxylic acid was 2 ~ 13% of that of sulfate and highest in summer. Changes in the stratus cloud top albedo and solar radiation net flux at the tropopause due to increases in number concentration of water soluble aerosols were calculated under three different scenarios of number concentrations. The calculations indicated that the indirect radiative effect caused by increases in number concentration of water soluble aerosols was large and a doubling in the number concentration of water soluble aerosols decreases the solar radiation net flux at the tropopause by up to 20 Wm2, although this occurs within a local cloudy area.

The Accuracy of Trajectory Calculations for Long-Range Transport of Air Pollutants
MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, Kondo Hiroki, Satoh Hisayasu
Proceedings of the Symposium on Global Environment, 4, 123, 128, Japan Society of Civil Engineers, 1996
The increasing attention to large-scale air pollution has resulted in numerous air monitoring networks and field studies. Trajectory calculations are often usedto understand the behavior of air pollutants and the results of measurements. However the accuracy of trajectory calculations is not well known, especially for the long-range transport in East Asia. In this study, some recent measurement data are used to determine the accuracy of isentropic trajectory model. The separation between isentropic trajectories and three-imensional trajectories derived from meteorological data which have sufficient temporal resolution is used to assess the validity of the isentropic technique. The results indicate that the isentropic trajectories arrived closest the boundary layer sometimes differ greatlyfrom three dimensional trajectories arrived at the surface measurement points. The causes of discrepancy is considered. Although the details of each trajectory do not necessarily reflect the actual path of motion of pollutants, the calculations suggest that the emsumble mode of trajectory analysis provides a useful tool of the relative patterns of large scale air motion.

Variation of Atmospheric Turbidity in Japanese Area
OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, FUKASAWA Tatsuya, HASEGAWA Shuichi, ARAO Kimio
Proceedings of the Symposium on Global Environment, 4, 117, 122, Japan Society of Civil Engineers, 1996
Atmospheric turbidity coefficients were calculated at five sites (Nemuro, Sapporo, Shionomisaki, Tosa-Shimizu and Ishigaki) in Japan from 1980 through 1995. Theturbidity coefficients ranged 0.03-0.30 at Nemuro, 0.05-0.45 at Sapporo, 0.05-0.45 at Shionomisaki, 0.03-0.40 at Tosa-Shimizu and 0.03-0.40 at Ishigaki. In 1982-1984 and 1991-1993 they had the maximum due to large volcanic eruptions of Mt. E1 Chichon and It.Pinatubo, respectively. Except effect of the volcanic eruption, the turbidity coefficients had tendency of increase from 1955 through 1990 due to increase of human activities. Global increase of the turbidity coefficient of 0.042 may cause the decrease of the global mean surface temperature of 0.3°C.

DEVELOPMENT OF CHEMICAL-TRANSPORT MODEL FOR THE TROPOSPHERE OF NORTHERN MID-LATITUDE
NAKAYAMA Satomi, MURAO Naoto, OHTA Satio, YAMAGATA Sadamu
Proceedings of the Symposium on Global Environment, 3, 225, 230, Japan Society of Civil Engineers, 1995
A two-dimensional channel model for the troposphere covering between 30N and 60N is constructed in order to simulate the effect of human activities on global troposphere. The model treats the processes of advection, diffusion, chemical transformation, emission from sources, dry and wet deposition and cloud transport. Calculated concentrations of ozone and PAN show a good agreement with observations. The amount of ozone is about10-20ppb, which accounts for 20-60% of present ozone concentration. This amount depends primarily on local NOxconcentration. Calculated distribution of PAN reflects temperature field. Furthermore, we run the model with the anthropogenic emissions from East Asia increased to the same emission strength of the most industrialized part of the U. S. HNO₃ concentration increased significantly near the source area at low levels, whereas PAN shows little dependence on height and longitude. The difference of these behavior is explained by the difference of their removal process from atmosphere. On the other hand, ozone shows 50% decrease in winter and 50% increase in summer near the surface over East Asia.

Variation of PAN Concentration in the lower Troposphere
MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, MIZOGUCHI Isao, KUBOTA Kazuhiko
Proceedings of the Symposium on Global Environment, 2, 114, 119, Japan Society of Civil Engineers, 1994
ABSTRACT;Analysis of PAN measurement in Sapporo indicated that the variation of PAN in Sapporo was highly affected by the transport from a wide area rather than the photochemical formation in Sapporo city. In this study, a two dimensional channel model for chemistry and transport in the troposphere is constructed to study the behavior of trace species at mid latitude in the northern hemisphere. Evaluation of the model performance is attempted with the results of our PAN measurements in Sapporo. The calculated seasonal variation of PAN concentrations at 140E near the surface, which shows a maximum in the late winter and a minimum in summer, presents a similar pattern to that observed in Sapporo. However the model tends to overpredict the concentrations during winter months and underpredict the concentrations during summer months.

Share the failures" that contribute to the endogenous development of renewable energy!　　　　　　　　　　　　　　　
YAMAGATA Sadamu, JUMIN TO JICHI MONTHLY, 703, 34, 34, Nov. 2021, [Lead author]
Japanese

President to be Dropped: Hokkaido University　　　　　　　　　　　　　　　
YAMAGATA Sadamu, Public universities being privatized, 56, 65, Sep. 2021, [Lead author]
Japanese, Introduction other

Hokkaido University and Military Research　　　　　　　　　　　　　　　
YAMAGATA Sadamu, Hokkaido University peace guide, 36, 37, Dec. 2019, [Lead author]
Japanese, Introduction other

Industry-Academia, Military-Academia Collaboration Today　　　　　　　　　　　　　　　
YAMAGATA Sadamu, 北海道大学ピースガイド, 99, 101, Dec. 2019, [Lead author]
Japanese, Introduction other

北海道における自然エネルギーへの展望－ブラックアウト（全域停電）の教訓を踏まえて－　　　　　　　　　　　　　　　
山形定, 自治と分権, 75, 79, 89, Apr. 2019, [Invited]
Japanese, Introduction other

ブラックアウトを経験した北海道で考える自然エネルギーの方向性　　　　　　　　　　　　　　　
山形定, 建築とまちづくり, 482, 18, 24, Feb. 2019, [Invited]
Japanese, Introduction scientific journal

センサーを用いた越境大気汚染の観測
村尾 直人, 山形 定, 深澤 達矢, 地球環境シンポジウム講演集, 22, 1, 4, Sep. 2014
土木学会, Japanese

Development of Wireless Sensor Network for Ozone Observation in Air Pollution Monitoring
UTIYAMA Masahiro, OKUMURA Satosi, KAWAKAMI Yosiyuki, NAKAGAWA Taro, YAMAGATA Sadamu, MURAO Naoto, JEC, 24, 1, 19, 24, 2014
A wireless sensor network was developed for continuously measuring ozone concentration in the atmosphere. The network was constructed of sensor nodes, each of which was made of an ozone sensor and a communications transmitter connected to a cellular phone network. In order to examine the performance of the sensor network, one-year observations were made at local air pollution monitoring stations in Sapporo and in Ayabe (in Kyoto Prefecture), and the ozone concentrations derived from the sensor outputs were compared with those obtained by the standard monitoring instruments. As a result, it was proved that the ozone sensor used in the node had enough ability to follow the change in the ozone concentration in the atmosphere. The correlation coefficients between the sensor network and the monitoring-station observations exceeded 0.86. Thus the ozone monitoring sensor network developed in this study was found to be at a stage of practical application., Japan Society for Environmental Chemistry, Japanese

Study on the influence of ammonium sulfate aerosol on cloud droplets utilizing Artificial Cloud Experimental System (ACES) with semi-real scale
山形 定, 三浦 二郎, 太田 幸雄, 藤吉 康志, 低温科学, 72, 21, 27, 2014
高度430mにおよぶ準実スケールの人工雲実験施設において硫酸アンモニウムエアロゾル粒子を発生させ, 雲核活性化が起きる高度40m程度までのエアロゾル, 雲粒について測定をおこなった. バックグラウンド粒子数濃度を低下させたことにより, 実験室用粒子発生装置を用いた安定的なエアロゾル粒子供給が可能となった. エアロゾル粒子および雲粒を同時に捕集可能な２段式インパクターを用い複数高度で両粒子の数濃度, 粒径分布を求めた.粒子発生用の硫酸アンモニウム溶液濃度を高くすると, 発生粒子個数が増加したが粒径に大きな変化は見られなかった. エアロゾル粒子数増加により生成する雲粒粒子数は増加, 雲粒径は減少し, Twomey効果が検証された.The volume fraction (ε) of water soluble material in atmospheric aerosol particles is an important parameter related to their hygroscopicity and activation processes to form cloud and ice particles. To estimateεof coarse dust particles, confocal scanning laser microscope was applied to measure the volume difference of individual particles before and after water dialysis directly. Individual particles (sphere equivalent diameter approx. 1-8 μm) of Asian reference dusts (CJ1 and CJ2) and atmospheric coarse particles during four Asian dust events were analyzed to ascertainε. Median values ofεfor CJ1 and CJ2 were, respectively, 29% and 13% with no size trend. Median values ofεfor coarse aerosol particles during two dust events were 18-42%. Dust particles with high εare potentially important for acting as giant CCN. Therefore aging of dust particles during transport might enhance the number of giant CCN over the North Pacific., 北海道大学低温科学研究所 = Institute of Low Temperature Science, Hokkaido University, Japanese

東アジアの森林を対象とした黒色炭素エアロゾルの葉面沈着量の評価
山田 哲郎, 村尾 直人, 山形 定, 地球環境シンポジウム講演集, 21, 231, 234, Sep. 2013
土木学会, Japanese

大気中の粒子状物質汚染の改善による健康便益の評価
服部 哲也, 村尾 直人, 山形 定, 地球環境シンポジウム講演集, 20, 197, 200, Sep. 2012
土木学会, Japanese

森林への黒色炭素粒子の乾性沈着に関するモデル評価
永田 大樹, 村尾 直人, 山形 定, 地球環境シンポジウム講演集, 20, 201, 204, Sep. 2012
土木学会, Japanese

Aerosols in Arctic troposphere in spring and summer: spatial features of aerosol constituents and their mixing states
Hara Keiichiro, Matsuki Atsushi, Yamagata Sadamu, Iwasaka Yasunobu, Yamanouchi Takashi, Herber Andreas, Antarctic record, 54, 0, 845, 867, 28 Dec. 2010
Airborne aerosol measurements around the Svalbard Archipelago were carried out in March-April, 2000 (ASTAR 2000) and in May-June, 2004 (ASTAR 2004) for better understanding of the spatial distribution of aerosol constituents and their mixing states. Major aerosol particles were sulfate particles in both campaigns. In ASTAR 2000 (spring), acidic sulfate particles (mostly H_2SO_4 droplets) were dominant, whereas the relative abundance of neutralized sulfate particles (probably (NH_4)_2SO_4) increased in the transition period (ASTAR 2004). Under Arctic haze conditions, higher relative abundance of aerosol particles containing soot was observed. Most of the soot collected during the haze was present as "external mixing states". In contrast, soot dominantly existed as "internal mixture" with sulfate particles under the background (non-haze) conditions. In the transition period (June in ASTAR 2004), the relative abundance of aerosol particles containing soot decreased clearly. Vertical features of sea-salt modification and spatial distribution of mineral particles are also reported., 国立極地研究所, Japanese

Scattering coefficient, size distribution and the transport process of tropospheric aerosol in the Arctic region observed with an aircraft during ASTAR 2000 2004 and AAMP 2002 campaign in spring
Yamagata Sadamu, Hara Keiichiro, Matsuki Atsushi, Antarctic record, 54, 0, 868, 881, 28 Dec. 2010
Airborne aerosol measurements of the Arctic haze were carried out during three campaigns, Arctic Study of Tropospheric Aerosol and Radiation 2000 (ASTAR 2000), the Arctic Airborne Measurement Program 2002 (AAMP 2002) and ASTAR 2004. Aircraft used for the campaigns were Dornier for ASTAR 2000 2004 and Gulfstream II for AAMP 2002. For all measurements aerosol particles were introduced into the cabin through stainless inlets and distributed to several instruments via a diffuser. Scattering coefficient of aerosol particles measured with an integrating nephelometer during the Arctic haze period showed a distinct difference between the lower, i.e. up to around 4000 m, and higher troposphere. Meanwhile, scattering coefficients in higher troposphere during the Arctic haze were in the same degree with those after the Arctic haze. Size distribution obtained from the data of a particle counter indicates that aerosol particles in accumulation mode during the Arctic haze have larger geometric mean diameter than those after the haze season, which reflects the aged air mass in the Arctic haze. "Curtain flight" which was carried out to reveal the fine structure of the haze layer showed that aerosol particles are transported in the isentropic plane., 国立極地研究所, Japanese

3H0900-4 Science of cloud/fog formation : Results from the Artificial Cloud Experimental Systems in vertical shafts of mines(Science of Fog and Its Environmental Effect-Toward 6th International Conference on Fog, Fog Collection and Dew 2013 in Yokohama-,S
YAMAGATA Sadamu, 大気環境学会年会講演要旨集, 50, 109, 110, 20 Aug. 2009
社団法人大気環境学会, Japanese

3E1040 Measurement of atmospheric black carbon concentration using integrating sphere(2 Method-3 field observation,General Presentations)
OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, 大気環境学会年会講演要旨集, 50, 507, 507, 20 Aug. 2009
社団法人大気環境学会, Japanese

3E1052 Measurement of extinction coefficient of aerosols collected on filters(2 Method-3 field observation,General Presentations)
SHIMIZU Yuji, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, 大気環境学会年会講演要旨集, 50, 508, 508, 20 Aug. 2009
社団法人大気環境学会, Japanese

Designing of GEOSS-SKYNET Aerosol Inlet and Its Evaluation Using Poly-Disperse Fly-Ash Particles
KANEYASU Naoki, YAMAGATA Sadamu, KOBAYASHI Hiroshi, Earozoru Kenkyu, 24, 3, 201, 208, 2009
Community aerosol inlet is designed for the super sites of SKYNET ground monitoring network in accordance with the guideline proposed by World Meteorological Organization/Global Atmosphere Watch project. The basic structure of this GEOSS-SKYNET inlet consists of a vertical pipe installed through the roof of the laboratory so that air is brought from the inlet top (>4.5 m from the ground level) to the iso-kinetic air splitter attached at the bottom of pipe with minimal bending. Aerosols are pre-separated at the inlet top with PM<SUB>10</SUB> impactor head which is newly designed for SKYNET super sites. The size separation characteristic of the inlet is tested with poly-dispersed fly-ash particles in a factory. The fly-ash particles collected on Nuclepore filters in the experiment were counted with Coulter counter method in 300 size bins. The obtained 50 % cut-off particle diameter of the inlet is 6.65 μm, which corresponds to 9.4 — 10.3 μm in aerodynamic diameter. Although the size separation characteristic of the inlet deviates from that of single-jet impactor with flat impaction plate in low Stokes Number region, it has better performance than commercially available PM<SUB>10</SUB> inlets in the region of relatively small Stokes number., Japan Association of Aerosol Science and Technology, Japanese

P-42 Health benefits analysis of particulate matter control in Kanto area(Poster (Academic Promenade))
SANADA Asumi, MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, 大気環境学会年会講演要旨集, 49, 430, 430, 29 Aug. 2008
社団法人大気環境学会, Japanese

1G1400 Variation of atmospheric hazardous particles over Japan(2 Method-1 measurement/analysis/2 Method-4 data analysis,General Presentations)
OTA Sachio, MURAO Naoto, YAMAGATA Sadamu, 大気環境学会年会講演要旨集, 49, 356, 356, 29 Aug. 2008
社団法人大気環境学会, Japanese

3D0930 Measurement of fog droplet with aerosol sensor(2 Method-3 field observation,General Presentations)
UCHIYAMA Masahiro, IZUMI Katsuyuki, MOMONO Kiyoyuki, HIRANO Yutaka, YAMAGATA Sadamu, 大気環境学会年会講演要旨集, 49, 569, 569, 29 Aug. 2008
社団法人大気環境学会, Japanese

ESTIMATION OF OPTICAL PROPERTIES OF AEROSOLS IN THE EAST CHINA SEA
Ogawa Kohei, Ohta Sachio, Murao Naoto, Yamagata Sadamu, Doboku Gakkai Ronbunshuu G, 15, 31, 36, 2007
Scattering coefficient, absorption coefficient. size distribution and mass of atmospheric aerosols were measured at Fukue Island in the East China Sea in March 2007. The scattering coefficient varied from 6 to 340Mm<SUP>-1</SUP> with an average of 67Mm<SUP>-1</SUP> at 530nm wavelength. and the absorption coefficient varied from 0.1 to 49Mm<SUP>-1</SUP> with an average of 7.6Mm<SUP>-1</SUP> at 565 nm wavelength. On March 22. the mass concentration increased with increase of scattering and absorption coefficients. which might be caused by long range transport of aerosols originated in the continental China., Japan Society of Civil Engineers

Estimation of changes in life expectancy due to exposure to particulate air pollutants in Japan
SANADA Asumi, MURAO Naoto, YAMAGATA Sadamu, OHTA Sachio, Doboku Gakkai Ronbunshuu G, 15, 63, 66, 2007
Although the Air Quality Standard achievement rate of Suspended Particulate Matter hasbeen improved recently, particulate air pollution is estimated to be one of the main environmental healthrisks in Japan. In this study, we estimate the changes in life expectancy due to the exposure to particulatesin urban area in Japan based on the relative risks obtained from a recent epidemiological study. The lifeloss expectancies (LLEs) for long-term exposure calculated for Yokohama city range from 1.0 to 1.8 years, which are comparable to those estimated for major European cities. These differences, however, comeslargely from social data such as age structure of the population and age-specific mortality rather thanparticulate concentrations., Japan Society of Civil Engineers

A Modeling study to estimate emission source contributions to the Arctic air pollution
MURAO Naoto, SATOH Kazuya, YAMAGATA Sadamu, OHTA Sachio, Doboku Gakkai Ronbunshuu G, 15, 67, 70, 2007
An Eulerian hemispheric model is used to investigate emission source contributions to the Arctic air pollution such as the Arctic haze and black carbon (BC) accumulation. Four cities, including Tiksi (71° 38' N, 128° 52' E), Barrow (71° 18' N, 156° 44' W), Alert (82° 28' N, 62° 30' W), and Spitsbergen (77° 55' N, 11° 56' E), are selected to evaluate the estimations. The results indicate that more than half of the wintertime sulfur deposition comes from emission sources in north America, and the contributions donot differ greatly with those in summer. The results from the calculations for BC suggests that three majoremission sources, namely open burning, biofuel, and fossil fuel, equally contribute to BC levels in thearctic cities., Japan Society of Civil Engineers

Application of PMF (Positive Matrix Factorization) method to daily wet deposition data in Japan
YAMASHITA Tomoo, MURAO Naoto, YAMAGATA Sadamu, OHTA Satio, HARA Hiroshi, Doboku Gakkai Ronbunshuu G, 15, 71, 76, 2007
Positive matrix factorization (PMF) was applied to daily wet deposition data fromthree satations in Japan to find the source profiles from which the precipitation samples areconstituted. For most ions more than 90% of the weighted variation was explained with 4 factors. Thefactors are characterized by the following compounds: strong acids (H<SUB>2</SUB>SO<SUB>4</SUB> and HNO<SUB>3</SUB>), (NH<SUB>4</SUB>) <SUB>2</SUB>SO<SUB>4</SUB>, NaCl, and CaSO<SUB>4</SUB>. Based on the chemical compositions of the factors, a time series of the factor contributions, andthe results from trajectory analysis, the factors are considered to represent sea salt, soil, (NH<SUB>4</SUB>) <SUB>2</SUB>SO<SUB>4</SUB> andacidity. Although the three stations show different temporal trends for total nss-SO4 wet deposition amount, the monthly contributions of the (NH<SUB>4</SUB>) <SUB>2</SUB>SO<SUB>4</SUB> factor to nss-SO<SUB>4</SUB> wet deposition were fairly constant for thestudying years. The acidity seemed to be controlled by the neutralization by soil particles., Japan Society of Civil Engineers

A PMF-based trajectory methodology applied to daily precipitation and wet deposition data in Japan
MURAO Naoto, HARA Hiroyuki, YAMAGATA Sadamu, OHTA Sachio, HARA Hiroshi, Doboku Gakkai Ronbunshuu G, 14, 199, 204, 2006
Positive matrix factorization (PMF) was applied to daily wet deposition data from three stations in Japan to find the source profiles from which the precipitation samples are constituted. For most ions more than 90% of the weighted variation was explained with 4 factors. The factors are characterized by the following compounds: strong acids (H<SUP>2</SUP>SO<SUB>4</SUB> and HNO<SUB>3</SUB>), (NH<SUB>4</SUB>)<SUB>2</SUB>SO<SUB>4</SUB>, NaCl, and CaSO<SUB>4</SUB>. The anion-cation balance was fairly good in the factors. Based on the chemical compositions of the factors, a time series of the factor contributions, and the results from trajectory analysis, the factors are considered to represent sea salt, soil, (NH<SUB>4</SUB>) <SUB>2</SUB>SO<SUB>4</SUB> and acidity. Although the total nss-SO<SUB>4</SUB> wet deposition amount decreased in the last 7 years at Wajima station, the contributions of the (NH<SUB>4</SUB>) <SUB>2</SUB>SO<SUB>4</SUB> factor to nss-SO<SUB>4</SUB> wet deposition were fairly constant (ca.50%). The acidity seemed to be controlled by the neutralization by soil particles., Japan Society of Civil Engineers

森林系木質バイオマスを利用するエネルギーシステムの評価
山﨑 高, 北野 智也, 秋本 裕輔, 山形 定, 村尾 直人, 太田 幸雄, 高津 宏和, 衛生工学シンポジウム論文集, 13, 147, 150, 16 Nov. 2005
第13回衛生工学シンポジウム（平成17年11月17日（木）-18日（金） 北海道大学クラーク会館） . 一般セッション . 4 建築 都市エネルギー利用 . 4-9, 北海道大学衛生工学会, Japanese

3-59. Monitoring of GC-detectable Tar by UV Absorption Spectroscopy
Yamazaki Takashi, Yamagata Sadamu, Murao Naoto, Ohta Sachio, Kozu Hirokazu, 日本エネルギー学会大会講演要旨集, 14, 14, 214, 215, 04 Aug. 2005
一般社団法人日本エネルギー学会, Japanese

Optical Properties Estimation from Chemical Composition Analysis of Atmospheric Aerosol in the East China Sea
NOKAME Kozue, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 13, 111, 116, 2005
In order to characterize optical properties of atmospheric aerosols in East Asia, the absorption coefficient (σ<SUB>ap</SUB>) and the scattering coefficient (σ<SUB>sp</SUB>) were monitored at three islands (Fukue Island, Miyako Island and Amami-ohshima Island) in East China Sea from 2002 through 2004. The optical properties ?Dap and ?Dsp at these islands showed high values in winter to spring and low values in summer. The single scattering albedo at Fukue Island ranged from 0.7 to 0.9. Further, aerosol measurement campaigns were performed in springs among the period. During the campaign besides the measurement of optical parameters, aerosol particles were collected on filters to determine chemical component concentrations. Using the chemical concentrations, σ<SUB>ap</SUB> and σ<SUB>sp</SUB> were calculated by Mie scattering theory for assumed mixing conditions and particle size distributions in aerosol model. The calculation use twenty kinds of particle size distributions and three mixing conditions as parameters. The best correlation with observed values were obtained in the geometric mean radius of 0.075?Em, the geometric standard deviation of 1.3 and external mixing condition., Japan Society of Civil Engineers

Tar production of partial oxidation of woody biomass using a downdraft gasifier
Yamazaki Takashi, Kozu Hirokazu, Yamagata Sadamu, Murao Naoto, Ohta Sachio, Doboku Gakkai Ronbunshuu G, 13, 225, 230, 2005
Changes in the amount and composition of tar according to superficial velocity (SV) were investigated in a downdraft biomass gasifier. SV of the downdraft gasification with air was varied in the range of 0.3-0.7m/s, and tar was recovered at the gasifier outlet. The tar was classified as gravimetric tar and gas-chromatography-detectable (GC-detectable) tar. The lowest gravimetric tar yield (0.7%) was obtained at 0.4m/s SV and the highest at 0.7m/s. GC-detectable tar yield was highest (1.5%) at 0.7m/s. One-ring aromatics and naphthalene accounted for more than 80% of GC-detectable tar mass. Some constituents of GC-detectable tar showed specific trends according to SV, although the main composition did not show extreme change. The effect of SV on the production of gases and particles was also studied., Japan Society of Civil Engineers

浮桟橋へのサンゴ移植の研究
久高 將佑, 平安山 武雄, 阿出川 隆之, 木原 一禎, 太田 幸雄, 山形 定, 山崎 高, 北野 智也, 帆秋 利洋, 天 石文, 高山 百合子, 岩田 芳隆, 信田 浩司, 小倉 礁, 三富 聡, 大友 祥太, 渡辺 義公, 市村 靖光, 鈴木 健, 大野 文良, 長谷 一矢, 多喜川 昇, 小林 仁, 岩崎 秀治, 篠原 伸和, 長 雄一, 高田 雅之, 大橋 和彦, 岡崎 克則, 金子 正美, 遠藤 大二, 浅川 満彦, 坪田 敏男, 淺野 玄, 赤松 里香, 小野寺 収, 濱田 靖弘, 後藤 隆一郎, 窪田 英樹, 中村 真人, 桑原 浩平, 長田 勉, 三浦 二郎, 松島 健将, 中島 義晴, 竹森 憲章, 樺澤 雅之, 渡辺 克実, 大山 成人, 久保 田学, 安保 芳久, 大束 淳一, 地球環境シンポジウム講演論文集, 13, 341, 366, 2005
Japan Society of Civil Engineers, Japanese

ダウンドラフト型ガス化炉を用いた木質バイオマスのガス化
山崎 高, 高津 宏和, 山形 定, 村尾 直人, 太田 幸雄, 椎谷 悟, 大場 龍夫, 衛生工学シンポジウム論文集, 12, 153, 156, 31 Oct. 2004
第12回衛生工学シンポジウム（平成16年11月4日（木）-5日（金） 北海道大学クラーク会館） . 一般セッション . 5 廃棄物処理とリサイクル . 5-4, 北海道大学衛生工学会, Japanese

Aerosol Chemical Species and Volatile Organic Compounds at Barrow, Alaska
MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, FUKASAWA Tatsuya, SHITABA Toshiaki, TAKEUCHI Kazuyuki, Journal of global environment engineering, 10, 11, 26, 01 Aug. 2004
English

3-32 Gasification of TODO Fir Chips with a Downdraft Gasifier
Yamazaki Takashi, Kozu Hirokazu, Yamagata Sadamu, Murao Naoto, Ohta Sachio, Shiya Satoru, Ohba Tatsuo, 日本エネルギー学会大会講演要旨集, 13, 13, 192, 193, 29 Jul. 2004
一般社団法人日本エネルギー学会, Japanese

A New Method for Measuring the Deposition Flux of Small-sized Water Droplets with a Polymeric Water Absorbent
IZUMI Katsuyuki, GHILAJIDIN Hurshida, UTIYAMA Masahiro, FUKUYAMA Tsutomu, YAMAGATA Sadamu, OHTA Sachio, Earozoru Kenkyu, 19, 2, 142, 148, 20 Jun. 2004
Fogs are thought to play an important role in deposition of acidic constituents in the atmosphere and also to be closely related to the decline of forests. We applied the polymeric water absorbent of a commercial diaper to the measurement of the deposition flux of fog water, for the first time. The absorbent was molded into a disk of 13 mm in diameter and 1mm in thickness, and characteristics of the disk, such as water vapor absorptivity and water retention ability, were studied in detail. Then we exposed the disk to the artificial fog in a cloud experiment facility, a large-scale vertical shaft (a long vertical passage or space in a mine) of Kamaishi Mine in Iwate Prefecture, in which a steady fog suitable for methodological studies on fogs was formed. The disks were hung on branches of a model pine tree, and the flux was determined from the increase in weight, the surface area of the disk and the exposure time to the fog. It was found through the present new method that the deposition flux was almost independent of wind directions, being 46 ∼ 65 g/m<SUP>2</SUP>/h. These values fell in the range of past data for tree leaves reported in literature., Japan Association of Aerosol Science and Technology, English

P349 立坑を用いた雲物理実験装置内で発生した雲の微物理過程(その7) : エアロゾルと雲粒の数濃度の対応
佐々木 聰, 播磨屋 敏生, 蝶野 洋平, 藤吉 康志, 太田 幸雄, 山形 定, 山田 正, 内山 政弘, 泉 克幸, 大会講演予講集, 85, 437, 437, May 2004
社団法人日本気象学会, Japanese

Seasonal Variation of Fog and Aerosol Chemistry off the Coast of East Hokkaido, Japan
MIURA Jiro, YAMAGATA Sadamu, OHTA Sachio, MURAO Naoto, Journal of Japan Society for Atmospheric Environment, 39, 2, 63, 76, 10 Mar. 2004
The influences of fog generation/evaporation on the properties of aerosol particles were investigated through the analyses of gas, aerosol particles and droplets off the coast of East Hokkaido in Japan during the foggy season (April and July, 2001) and non-foggy season (October, 2000 and January, 2001). Case study of a single fog event indicates that 1) SO_2, NH_3 and HNO_3 gas were dissolved in droplets above 2μm in diameter during a fog event and 2) Na^+ concentration in fine particles (<2μm) increased during evaporation stage suggesting droplet splashing. Particle fractions (PF) and fine particle fractions (FPF) in all seasons were analyzed to evaluate the influences of fog on aerosol particles. In foggy season, the average PF of SO_4^<2-> and NH_4^+ were higher than those of non-foggy season indicating that the dissolution of gas under foggy generation. On the other hand the average FPF of Na^+ in foggy season were 3 times as large as non-foggy season suggesting that droplets splash during the evaporation of fog droplets. From these results it is concluded that fog cycles play roles in seasonal variation of aerosol chemistry in this area., 公益社団法人大気環境学会, Japanese

テープ式吸収率計の開発と黒色純炭素連続測定への適用
加藤 秀樹, 村尾 直人, 山形 定, 太田 幸雄, 環境工学研究論文集, 41, 105, 110, 2004
Using tape type filter, an absorption photometer suitable for continuous absorptioncoefficient monitoring in remote area and black carbon (BC) monitoring in urban area was developed. This instrument is equipped with two fiber optic sensors, monitoring reflected light from aerosolcollecting spot and non-collecting part of the filter. The latter signal was used as a reference tocorrect the shift of the sensor sensitivity caused by temperature fluctuations. Collection spot was automaticallychanged when the signal from the spot decreased below a threshold value. Measurements were conductedin Sapporo in October and November 2003 (period-I), and February and March 2004 (period-II) toevaluate and characterize the instrument. The good correlation between absorption coefficients measure by the instrument and EC concentrations measured by thermal method was found (R<SUP>2</SUP>=0.961 at period-I and R<SUP>2</SUP>=0.797 at period-II). One-hour BC concentrations calculated based on the regressions rangedfrom 0.5 to 7.8μg/m<SUP>3</SUP>. The instrument was found to be easy to use and had sufficient sensitivity to beuseful in atmospheric monitoring., Japan Society of Civil Engineers, Japanese

大気汚染常時監視測定局のＮＯｘ測定値を用いた札幌市におけるディーゼル排気微粒子に起因する発ガンリスクの推定
加藤 秀樹, 村尾 直人, 山形 定, 太田 幸雄, 環境工学研究論文集, 41, 111, 117, 2004
Cancer risk from diesel exhaust particle (DEP) was estimated using data collected at ambient and roadside air monitoring stations in Sapporo. DEP concentrations were calculated based on the three assumptions: i) 90% of ambient elemental carbon (EC) originate from DEP, ii) 40% of DEP consists of EC, and iii) Human exposed DEP concentration is 80% of ambient DEP concentration. The cancer risks from polycyclic aromatic hydrocarbons (PAHs) and nitro-polycyclic aromatic hydrocarbons (NPAHs) were compared to the cancer risk from DEP (1.3×10<SUP>-3</SUP> in summer and 1.5×10<SUP>-3</SUP> in winter). The sum of the cancer risks from five PAHs and three NPAHs (1.1×10<SUP>-7</SUP> in summer and 4.1×10<SUP>-7</SUP> in winter) was much less than that from DEP. The correlation between EC and available data (NOx and SPM) at the air monitoring station in Sapporo was examined. EC and NOx showed higher correlations (R<SUP>2</SUP>=0.583 (summer), 0.775 (winter)) than EC and SPM. DEP cancer risks were calculated for each air monitoring stations with the regression between EC and NOx. The risks for the ambient air monitoring stations and roadside air monitoring stations ranged from 8.4×10-4 to 1.5×10<SUP>-3</SUP> and 1.4×10<SUP>-3</SUP> to 2.5×10<SUP>-3</SUP>, respectively., Japan Society of Civil Engineers, Japanese

Seasonal Variation of Fog and Aerosol Chemistry off the Coast of East Hokkaido, Japan.
MIURA Jiro, YAMAGATA Sadamu, OHTA Sachio, MURAO Naoto, Journal of Japan Society of Air Pollution, 39, 2, 63, 76, 2004
The influences of fog generation/evaporation on the properties of aerosol particles were investigated through the analyses of gas, aerosol particles and droplets off the coast of East Hokkaido in Japan during the foggy season (April and July, 2001) and non-foggy season (October, 2000 and January, 2001). Case study of a single fog event indicates that 1) SO<SUB>2</SUB>, NH<SUB>3</SUB> and HNO<SUB>3</SUB> gas were dissolved in droplets above 2μm in diameter during a fog event and 2) Na<SUP>+</SUP> concentration in fine particles (<2μm) increased during evaporation stage suggesting droplet splashing.<BR>Particle fractions (PF) and fine particle fractions (FPF) in all seasons were analyzed to evaluate the influences of fog on aerosol particles. In foggy season, the average PF of SO<SUB>4</SUB><SUP>2-</SUP>and NH<SUB>4</SUB><SUP>+</SUP>were higher than those of non-foggy season indicating that the dissolution of gas under foggy generation. On the other hand the average FPF of Na<SUP>+</SUP> in foggy season were 3 times as large as non-foggy season suggesting that droplets splash during the evaporation of fog droplets. From these results it is concluded that fog cycles play roles in seasonal variation of aerosol chemistry in this area., Japan Society for Atmospheric Environment, Japanese

Artificial Cloud Experiment in a Vertical Shaft in a Mine
YAMAGATA Sadamu, Earozoru Kenkyu, 18, 4, 266, 270, 20 Dec. 2003
Artificial Cloud Experiment Systems (ACES) in a vertical shaft of a mine were established at a coal mine in Kami-sunagawa, Hokkaido then at an iron mine in Kamaishi, Iwate. Updraft of air by electric fans induced the adiabatic expansion of air that resulted in generation of artificial clouds. We conducted basic measurements of temperature profiles, updraft air velocity, size distribution of droplets, etc. and investigated the dissolution of SO<SUB>2</SUB> into cloud droplets, the oxidation of sulfite to sulfate, and the flux of droplet deposition onto trees using the stable cloud in ACES. Recent improvements of experimental conditions allowed for precise experiments in studying the influence of aerosol properties on the cloud properties which is the key process of indirect radiative forcing by aerosol particles., Japan Association of Aerosol Science and Technology, Japanese

P403 準実スケール実験によるエアロゾル粒径分布と雲粒粒径分布の関係
野田 和宏, 播磨屋 敏生, 佐々木 聰, 藤吉 康志, 山形 定, 山田 正, 内山 政弘, 泉 克幸, 雲物理観測グループ, 雲物理観測グループ, 大会講演予講集, 83, 21 May 2003
社団法人日本気象学会, Japanese

Measurement of Hazardous Air Pollutants in Alaska and Estimates of Source Contr butions
SHITABA Toshiaki, MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 11, 105, 110, 2003
VOCs and aerosols measurements were conducted at Barrow, Alaska, USA from July, 1999 to July, 2001, to obtain their seasonal variation. Heavy metals, EC and sulfate concentration showed minimum in summer and autumn, and maximum in winter and spring, which is a character of Arctic Haze. Some VOCs (Xylene etc.) also showed the same seasonal variation, which suggest that VOCs are the component of Arctic Haze.<BR>Source contributions of aerosols samples at Barrow were estimated by using a new type of factor analysis, positive matrix factorization (PMF). The PMF analysis identified three factors that indicate three aerosol sources contribute to aerosol concentrations at Barrow. The first factor was considered to represent sea salt, and remaining two factors were considered to represent anthropogenic sources.<BR>To verify a difference in transport pathways between sampling periods, 5day backward trajectories were constructed. In winter and spring, some trajectories indicated long-range transport from emission sources in Eurasia. It was thus considered that long-range transport from emission sources in Eurasia was one of the causes of Arctic Haze at Barrow., Japan Society of Civil Engineers

The measurement of atmospheric aerosol components exhausted from diesel vehicles in Sapporo
Kozu Hirokazu, Murao Naoto, Yamagata Sadamu, Oota Sachio, 大気環境学会年会講演要旨集, 44, 332, 332, 2003
社団法人大気環境学会, Japanese

Measurement of the liquid water content of fogs (LWC) with a polymeric water absorbent : (1) Basic experiments with artificial fogs generated in a long-vertical shaft at Kamaishi Mine
Izumi Katsuyuki, Uchiyama Masahiro, Fukuyama Tsutomu, Yamagata Sadamu, Ohtara Sachio, Sasaki Akira, Harimaya Toshio, 大気環境学会年会講演要旨集, 44, 388, 388, 2003
社団法人大気環境学会, Japanese

Characteristics of latitudal distribution of optical and chemical properties of atmospheric aerosols over the Pacific Ocean
Fujitani Yuji, Oota Sachio, Murao Naoto, Yamagata Sadamu, 大気環境学会年会講演要旨集, 44, 449, 449, 2003
社団法人大気環境学会, Japanese

Estimation of diesel exhaust particle concentration using continuous elemental carbon analyzer
Kato Hideki, Murao Naoto, Yamagata Sadamu, Oota Sachio, 大気環境学会年会講演要旨集, 44, 579, 579, 2003
社団法人大気環境学会, Japanese

The development of a continuous measuring instrument for the absorption coefficient of atmospheric aerosol
Nokame Kozue, Yamagata Sadamu, Oota Sachio, Murao Naoto, 大気環境学会年会講演要旨集, 44, 649, 649, 2003
社団法人大気環境学会, Japanese

Size-distribution measurement of artificial cloud using a impactor with shifting impaction plate
Ishiguro Takahiko, Yamagata Sadamu, Oota Sachio, Murao Naoto, Fujiyoshi Yasushi, 大気環境学会年会講演要旨集, 44, 674, 674, 2003
社団法人大気環境学会, Japanese

Simultaneous observation of cloud droplets and aerosol particles just above the artificial cloud base produced in a vertical shaft
Miura Jiro, Yamagata Sadamu, Oota Sachi, Murao Naoto, 大気環境学会年会講演要旨集, 44, 681, 681, 2003
社団法人大気環境学会, Japanese

航空機を用いた北極上空大気エアロゾルの観測
山崎 高, 山形 定, 村尾 直人, 太田 幸雄, 和田 誠, 山内 恭, 衛生工学シンポジウム論文集, 10, 125, 128, 31 Oct. 2002
第10回衛生工学シンポジウム（平成14年10月31日（木）-11月1日（金） 北海道大学学術交流会館） . 4 環境計測 . P4-7, 北海道大学衛生工学会, Japanese

フィルターを監（み）る
山形 定, 吉舗 大, 村尾 直人, 太田 幸雄, 衛生工学シンポジウム論文集, 10, 129, 132, 31 Oct. 2002
第10回衛生工学シンポジウム（平成14年10月31日（木）-11月1日（金） 北海道大学学術交流会館） . 4 環境計測 . P4-8, 北海道大学衛生工学会, Japanese

北海道東部太平洋沿岸におけるエアロゾルの季節変化
三浦 二郎, 太田 幸雄, 村尾 直人, 山形 定, 大会講演予講集, 82, 09 Oct. 2002
Japanese

大気エアロゾルの屈折率の測定
加藤 潤, 太田 幸雄, 村尾 直人, 山形 定, 大会講演予講集, 82, 144, 144, 09 Oct. 2002
Japanese

土壌粒子の光学的吸収率の測定
石黒 貴彦, 太田 幸雄, 村尾 直人, 山形 定, 大会講演予講集, 82, 178, 178, 09 Oct. 2002
Japanese

アラスカにおける有害大気汚染物質の測定
下羽 利明, 村尾 直人, 太田 幸雄, 山形 定, 大会講演予講集, 82, 280, 280, 09 Oct. 2002
Japanese

クロージャー研究による大気エアロゾルの粒径分布・混合状態モデルの検討
長谷川 就一, 太田 幸雄, 加藤 亮, 村尾 直人, 山形 定, 大会講演予講集, 82, 412, 412, 09 Oct. 2002
Japanese

1C1115 Filter techniques for measurement of ambient nitrogen oxides
Hirato Y, Murao N, Ohta S, Yamagata S, 大気環境学会年会講演要旨集, 43, 252, 252, 11 Sep. 2002
社団法人大気環境学会, Japanese

1F1130 Measurement of absorpotion coefficients of soil particles
Ishiguro T, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 43, 269, 269, 11 Sep. 2002
社団法人大気環境学会, Japanese

1F1145 Measurement of refractive indices of aerosol particles
Kato J, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 43, 270, 270, 11 Sep. 2002
社団法人大気環境学会, Japanese

1F1515 Measurement of optical and Chemical properties of atmospheric aerosol with R/V MIRAI
Fujitani Y, Ohta S, Murao N, Yamagata S, Endoh T, 大気環境学会年会講演要旨集, 43, 341, 341, 11 Sep. 2002
社団法人大気環境学会, Japanese

3C0900 Seasonal variation of aerosol in coastal Pacific, Hokkaido, Japan
Miura J, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 43, 514, 514, 11 Sep. 2002
社団法人大気環境学会, Japanese

3J1145 Development of Sampling Photometer
Yamagata S, Yoshiki D, Murao N, Ohta S, 大気環境学会年会講演要旨集, 43, 588, 588, 11 Sep. 2002
Japan Society for Atmospheric Environment, Japanese

Airborne measurement of ionic components in aerosol particles during AAMP98 (in Japanese)
Yamagata Sadamu, Shoji Katsuhiro, Murao Naoto, Ohta Sachio, Antarctic record, 46, 1, 167, 176, Jun. 2002
北極圏航空機観測1998 (AAMP 98）中， 大気エアロゾルをガルフストリームIIのインレットから機内に導入し，ディフューザーで減速した後，テフロンフィルター上に捕集した．ディフューザー内の0.3µm以上の粒径を持つ粒子数濃度をフィルターサンプリングのラインと並列につないだオプティカルパーティクルカウンタ（OPC）でモニタ ーした. OPCのデータはシリアル通信でパソコンに転送，記録した．フィルターサンプルは実験室に持ち帰り，イオン交換水で抽出後イオンクロマトグラフを用い、陽・陰イオン濃度を測定した．Cl^- , N02^- , NO3^- , SO4^2-, Na^+ , NH4^+, K^+, Mg^2+, Ca^2＋のイオンが検出された．成層圏にはSO4^2- を含んだエアロゾル層が知られているが，本観測では，これに加えCl^-, Ca^2＋が上空でしばしば検出された．During the Arctic Airborne Measurement Program 1998 (AAMP 98), atmospheric aerosols were collected onto PTFE filters from the inlet of Gulfstream II through a diffuser installed in the cabin. During the sampling the number concentrations of aerosol particles with diameters larger than 0.3 µm were continuously monitored with an optical particle counter (OPC) connected to the diffuser in parallel to the filter sampling line. The data from the OPC were transferred by serial communication to a computer and recorded. The filter samples were brought back to the laboratory, then extracted with ion exchanged water and the concentrations of anions and cations were analyzed by ion chromato­graphy. Detected ions were as follows: Cl^-, N02^-, 1 , N03^-, SO4^2-, Na^+, NH4+, K^+, Mg^2+, Ca^2+. Even at high altitudes Cl^- and Ca^2+ were frequently detected, in addition to SO4^2- , which is known as a major ionic component in the stratosphere., 国立極地研究所, Japanese

Measurements of particle number mixing ratio with aircraft-borne Optical Particle Counter (in Japanese)
Watanabe Masaharu, Iwasaka Yasunobu, Nagatani Masahiro, Nakata Hiroshi, Yamagata Sadamu, Inomata Yayoi, Sakai Tetsu, Antarctic record, 46, 1, 177, 229, Jun. 2002
98年3月に名古屋を起点として北極点を横断する北極航空機観測計画AAMP 98が実施された．ガルフストリームII型双発ジェット機の胴体下部に光散乱式粒子計数器（Optical Particle Counter, OPC）が搭載され，中緯度～極域の対流圏，成層圏エアロゾル粒子数混合比が計測された．観測結果は成層圏（高度12 km巡航）では水平方向には非常に粒子数の変化が少ない，安定した数濃度分布の状態を示したが，数カ所で粒子数に大きな変化が見られた．客観解析，および流跡線解析デー タと比較した結果，極ジェット外縁部，特に気圧の谷東側付近で発生している温暖コンベアーベルトの影響を受けた上昇気流が，この粒子数変化の原因である可能性が高いことが分かった．Particle number mixing ratios of tropospheric and stratosphenc aerosols were observed in the Arctic Airborne Measurement Program 1998 (AAMP 98) using an Optical Particle Counter onboard a sub-sonic aircraft, the Gulfstream II (G-11) in March 1998. The observational results showed horizon­tally homogeneous distributions of particle number mixing ratio at the cruise altitude (about 12 km). On the other hand, distinct size-number distributions were found at some points on the flight paths, which suggest that effects of the warm conveyor belts appeared eastward of trough of atmospheric pressure. The characteristics of observed particle size-number distributions are discussed with isentropic backward trajectory analyses and geopotential maps., 国立極地研究所, Japanese

Direct sampling of atmospheric aerosol particles during Arctic Airborne Measurement Program (AAMP 98) (in Japanese)
Hara Keiichiro, Iwasaka Yasunobu, Inomata Yayoi, Osada Kazuo, Matsunaga Katsuji, Yamagata Sadamu, Nagatani Masahiro, Nakata Hiroshi, Antarctic record, 46, 1, 230, 242, Jun. 2002
春季北極大気中の大気エアロゾル粒子の性状を知るために， AAMP98において境界層内～成層圏下部にかけて，大気エアロゾル粒子の直接採集を行った．捕集されたエアロゾル粒子は，走査型電子顕微鏡—エネルギ一分散型X線分析装置により，形態観察と組成分析を行った．対流圏～成層圏下部の全体の空間では，硫酸と見られるSを含む粒子が多数を占めていた．また，土壌・ ダスト粒子と考えられる不定形粒子，海塩粒子のような結晶質の粒子は境界層内～約7000 mに確認された．In order to know the morphology and mixing state of atmospheric aerosol particles in the spring Arctic atmosphere, direct sampling of aerosol particles was carried out using an aerosol impactor system during the Arctic Airborne Measurement Program (AAMP 98). Aerosol samples were observed with a scanning electron microscope and analyzed with an energy-dispersive X-ray spectrometer. Aerosol particles with clear satellite structure due to sulfuric acid droplets were observed in samples collected in the lower stratosphere and free troposphere. On the other hands, aerosol particles with crystal and satellite structure due to droplets of sea salt particles were observed in the boundary layer., 国立極地研究所, Japanese

Aerosol observations at Ny-Ålesund, Svalbard from December 1997 to March 1998 (in Japanese)
Wada Makoto, Yamagata Sadamu, Kikuchi Tadashi, Antarctic record, 46, 1, 261, 268, Jun. 2002
1997年12月15日から1998年3月日日までの期間，北極圏スパ ールパル諸島ニーオルスンにおいてエアロゾルの観測を行った．本報告では，主としてパーティクルカウンターのデータを用い、他の観測デー タを参考にして，この期間のエアロゾル個数濃度の変動を報告する．さらに北極圏航空機観測（Arctic Airborne Measurement Program 1998: AAMP 98）がスパールパル諸島周辺で行われた1998年3月8日から10日のエアロゾル，雲，降水のデー タについて，他の観測デー タの参考になるので，より詳細に報告し，エアロゾル濃度の変動の原因について考察した．Aerosol observations were carried out at Ny-Alesund, Svalbard. Arctic from December 15, 1997 to March 11, 1998. Variation of aerosol particle number in the period measured by the optical particle counter is reported in this paper. Three observational flights around Svalbard were carried out between March 8 and 10,1998. The flights were part of the Arctic Airborne Measurement Program 1998 (AAMP 98). Detailed data in the above period are also reported for supporting discussions with flight observation data., 国立極地研究所, Japanese

BACKWARD TRAJECTORY ANALYSIS OF AIR POLUTANTS MEASURED AT BARROW, ALASKA
SHITABA Toshiaki, MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 10, 209, 214, 2002
VOCs and aerosols sampling was conducted at Barrow, Alaska, USA from July, 1999 to July, 2001, to obtain their seasonal variation.Heavy metals, EC and sulfate concentration showed minimum in summer and autumn, and maximum in winter and spring, which is the character of Arctic Haze.Some VOCs (Xylene etc.) also showed the same seasonal variation, which suggest that VOCs are the component of Arctic Haze.<BR>To verify a difference in transport pathways between in winter and in summer, 5day backward trajectories were constructed. In winter and spring, some trajectories indicated long-range transport from emission sources in Eurasia. It was thus considered that long-range transport from emission sources in Eurasia was one of the causes of Arctic Haze at Barrow., Japan Society of Civil Engineers

REEVALUATION OF THE CONTRIBUTION OF COS TO FORMING STRATOSPHERIC SULFATE AEROSOL
ITOH Akiyoshi, MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 10, 215, 220, 2002
In this study stratospheric sulfate production from carbonyl sulfide (COS) oxidation is calculated with a steady-state photochemical model including the currently available photochemical parameters. As a result, the sulfate production in the stratosphere is estimated to be 2 to 5 times larger than that obtained from previous studies by other authors. Additionaly, the production is evaluated by 40 to more than 100% with regard to estimates of sulfate required to sustain the stratospheric background aerosol layer. Based on these results, contribution of COS to the stratospheric sulfate production can not be ignored. In the view of seasonal and latitudinal trend, sulfate production in the stratosphere is shown to be dominant in summer and tropics., Japan Society of Civil Engineers

立坑を用いた雲物理実験装置内で発生した雲の微物理過程(その6)-上昇流速の影響
佐々木 聰, 播磨屋 敏生, 藤吉 康志, 山形 定, 山田 正, 福山 力, 泉 克幸, 大会講演予講集, 80, 51, 51, 10 Oct. 2001
Japanese

1I0930 Filter techniques for measurement of ambient nitrogen dioxide
Ikeya Y, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 42, 298, 298, 06 Oct. 2001
社団法人大気環境学会, Japanese

1E1415 Measurement of nitrogen dioxide distribution using passive sampler in Sapporo
Onozuka A, Ohta S, Murano N, Yamagata S, 大気環境学会年会講演要旨集, 42, 352, 352, 06 Oct. 2001
社団法人大気環境学会, Japanese

1H1300 Variation in atmospheric turbidity in Japan
Hasegawa S, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 42, 377, 377, 06 Oct. 2001
社団法人大気環境学会, Japanese

1H1345 Optical and chemical properties of the atmospheric aerosol in Amami-Ohshima island, Japan
Kato R, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 42, 380, 380, 06 Oct. 2001
社団法人大気環境学会, Japanese

1H1430 Measurement of optical and chemical properties of atmospheric aerosols over the western Pacific Ocean
Fujitani Y, Ohta S, Murao N, Yamagata S, Endo T, 大気環境学会年会講演要旨集, 42, 383, 383, 06 Oct. 2001
社団法人大気環境学会, Japanese

1I1315 Measurement of ambient ammonium gas by a detector with an optical fiber sensor
Yamazaki T, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 42, 388, 388, 06 Oct. 2001
社団法人大気環境学会, Japanese

1I1430 Evaluation of the sampling with quartz filter for the measurement of atmospheric organic aerosol
Murai K, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 42, 393, 393, 06 Oct. 2001
社団法人大気環境学会, Japanese

2F0945 Marine fog chemistry in the Pacific coastal Areas of Hokkaido, Japan
Miura J, Ohta S, Nurao N, Yamagata S, Nishio F, 大気環境学会年会講演要旨集, 42, 499, 499, 06 Oct. 2001
社団法人大気環境学会, Japanese

準実スケールの雲物理実験装置で検出した過飽和層
藤吉 康志, 青木 一真, 久保田 圭, 播磨屋 敏生, 山形 定, 山田 正, 内山 政弘, 泉 克幸, 大会講演予講集, 79, 78, 78, 08 May 2001
Japanese

春季北極対流圏中の大気エアロゾル成分とその混合状態 : ASTAR 2000での飛行機観測結果
原 圭一郎, 岩坂 泰信, 山内 恭, 塩原 匡貴, 佐藤 薫, 山形 定, HERBER Andreas, 長谷 正博, 中田 滉, 大会講演予講集, 79, 252, 252, 08 May 2001
Japanese

REMOTE SENSING OF AEROSOL OPTICAL THICKNESS ON THE EAST CHINA SEA
HASEGAWA Shuichi, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 9, 175, 180, 2001
Aerosol optical thickness on the East China Sea was evaluated by using radiances observed by Terra-MODIS. We measured optical and chemical properties of aerosols such as scattering and absorption coefficient, chemical composition, and optical thickness in Fukue Island, Nagasaki Prefecture. The optical thickness was calculated from the single scattering albedo, phase function, and reflectance of sea surface based on the measurement synchronized with Terra-MODIS. The evaluated optical thickness at the wavelength of 1μ m agreed well with that observed in Fukuoka. The optical thickness on the coastal sea of Korea Peninsula was larger than that on off the shore. This suggested that it is also important to determine the surface reflectance on the coastal sea that eutrophication or flowage of sand from rivers may occur., Japan Society of Civil Engineers

Measurement of optical properties of atmospheric aerosols in the western Pacific Ocean
FUJITANI Yuji, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, ENDOH Tatsuo, Doboku Gakkai Ronbunshuu G, 9, 181, 186, 2001
It is necessary to assess the spatial distribution and variation of optical properties and chemical species of atmospheric aerosols to estimate the direct effect on climate. In the western Pacific Ocean, where the pollutants are transported from the East Asia, there are little aerosol measurements available to estimate the climate effect. In this study the aerosol optical and chemical properties were measured in June-July 2000 in the western Pacific Ocean on board the research vessel Mirai. In the southern area of 30° N, it was found that the area was under marine background condition due to less concentration of anthropogenic elements of aerosols such as V, Ni and Pb than those in the area north of 30° N. In south of 30° N, absorption coefficient (σ<SUB>ap</SUB>) were extremely low as those less than 2× 10<SUP>-7</SUP>m<SUP>-1</SUP>, and scattering coefficients (σ<SUB>ap</SUB>) ranged from 80× 10<SUP>-7</SUP>m<SUP>-1</SUP> to 212× 10<SUP>-7</SUP>m<SUP>-1</SUP>. The single scattering albedo (ω), then, ranged from 0.97 to 0.99, which shows the aerosols were highly transparent in summer in the western Pacific Ocean., Japan Society of Civil Engineers

Measurement of Hazardous Air Pollutants in Alaska
TAKEUCHI Kazuyuki, OHTA Sachio, MURAO Naoto, YAMAGATA Sasamu, Doboku Gakkai Ronbunshuu G, 9, 187, 192, 2001
Atmospheric concentrations of volatile organic compounds (VOCs), trace metals (vanadium, lead, etc), sulfate and elemental carbon (EC) were measured at Barrow, Alaska, USA (71.32N, 156.60W) during July, 1999-December, 2000. The concentrations of nine VOCs (i. e. Xylene, Ethylbenzene, Stylene etc.), EC, sulfate and four trace metals (i.e. Ni, V, As and Pb) showed a similar seasonal variation with a broad maximum extending from winter to spring. Because EC, trace metals and sulfate are major component of "Arctic haze", good agreement of seasonal variations between these species and VOCs suggests that VOCs, together with EC, trace metals and sulfate, are transported over distances of several thousands of km from industrialized areas in mid-latitude., Japan Society of Civil Engineers

Measurement of air pollution in Norilsk
Fukasawa Tatsuya, Ohta Sachio, Enomoto Kyoichi, Murao Naoto, Yamagata Sadamu, Shimizu Tatsuo, Makarov Vladimir N., Rastegaev Igor, Polar meteorology and glaciology, 14, 92, 102, Nov. 2000
Air pollution, deposition and its accumulation in surface soil were investigated in Norilsk, Russia. Concentrations of SO_2 and NO_2 gas were measured in Norilsk by using passive samplers 29 July-4 August 1993 and 31 July-4 August 1995. SO_2 concentrations were more than 100ppb in downtown Norilsk; the highest value was 260ppb in 1995. On the other hand, NO_2 concentrations were rather lower than those in Sapporo, Japan. Aerosol chemical species were continuously measured from summer 1993 to summer 1995 at Norilsk Experimental Center in downtown Norilsk. Major components of aerosol chemical species were sulfate (0.9-16μgm^<-3>), organics (1.6-12μgm^<-3>) and elemental carbon (0.1-4.2μgm^<-3>). The ranges of heavy metal concentrations (ng m^<-3>) were Cu, 2-300; Pb, 0.5-83 and Ni, 1-48 with no significant seasonal variations, about ten times more than those in Sapporo. We also collected larch needles, mosses and soil samples to evaluate the deposition and accumulation of the air pollutants. The concentrations of heavy metal and sulfate in larch needles, mosses and surface soil samples decrease with distance from the center of Norilsk. Heavy metal concentrations in deep soil (20-30cm) were nearly equal to the global mean, whereas the concentrations in surface soil (5-10cm depth) were several times to hundreds times higher than those in deep soil (20-30cm depth). This suggests that the emitted pollutant has been deposited and accumulated in surface soil for 40 years, since the nickel-copper smelting companies started operations., National Institute of Polar Research, English

北極対流圏エアロゾル・放射総合観測ASTAR 2000 (Arctic Study of Tropospheric Aerosol and Radiation) : 日本・ドイツ共同航空機・地上同期観測
山内 恭, 塩原 匡貴, 平沢 尚彦, 佐藤 薫, 和田 誠, 山形 定, 藤谷 雄二, 原 圭一郎, 柴田 隆, 西田 千春, 矢吹 正教, HERBER A, 大会講演予講集, 78, 272, 272, 18 Oct. 2000
Japanese

3波長ネフェロメータおよびOPCを用いた、大気エアロゾル複素屈折率の導出 : ASTAR2000ニーオルスン地上観測
矢吹 正教, 塩原 匡貴, 山内 恭, 平沢 尚彦, 原 圭一郎, 藤谷 雄二, 山形 定, 西田 千春, 柴田 隆, 竹内 延夫, 久世 宏明, 大会講演予講集, 78, 385, 385, 18 Oct. 2000
Japanese

課題(11-14):海洋地球観測船「みらい」による海洋上大気エアロゾルの観測(新規)(2.2一般研究)([2]共同利用研究(平成11年度))
太田 幸雄, 村尾 直人, 山形 定, 上田 厚志, 千葉大学環境リモートセンシング研究センター年報, 5, 27, 27, Oct. 2000
千葉大学, Japanese

1E1130 Size distribution of chemical species in atmospheric aerosol particles
Ohta S, Hayashi M, Yamagata S, Murao N, 大気環境学会年会講演要旨集, 41, 228, 228, 26 Sep. 2000
社団法人大気環境学会, Japanese

1E1145 Optical property measurements of soil particles
Ohta S, Kato R, Hasegawa S, Yamagata S, Murao N, 大気環境学会年会講演要旨集, 41, 229, 229, 26 Sep. 2000
社団法人大気環境学会, Japanese

1F1115 Simultaneous quantification of chemical components in atmospheric aerosols by thermal analysis
Yamagata S, Yoshiki D, Murao N, Ohta S, 大気環境学会年会講演要旨集, 41, 237, 237, 26 Sep. 2000
社団法人大気環境学会, Japanese

1F1345 Atmospheric NO_2 measurement by diffusion scrubber
Yamagata S, Kimijima T, Murao N, Ohta S, 大気環境学会年会講演要旨集, 41, 317, 317, 26 Sep. 2000
社団法人大気環境学会, Japanese

1L1515 Optical properties of aerosol in the Arctic observed with airplane
Fujitani Y, Yamagata S, Ohta S, Murao N, Yamanouchi T, Shiobara M, Hara K, Herber Andreas, 大気環境学会年会講演要旨集, 41, 375, 375, 26 Sep. 2000
社団法人大気環境学会, Japanese

MASUREMENT OF PEROXYACETYL NITRATE IN SAPPORO JAPAN
TSUZAKI Masaharu, MURAO Naoto, YAMAGATA Sadamu, OHOTA Sachio, Doboku Gakkai Ronbunshuu G, 8, 289, 294, 2000
Peroxyacetyl Nitrate (PAN) measurement were made at Sapporo from July 1997 to September 1999 and at Mt. Teine (1000m altitude), a site near Sapporo urban area, from February to May 1999. Median concentrations of PAN for each month show seasonal variation. Maximum levels of about 0.3-0.4ppb were observed during winter months. On sunny days in summer PAN concentrations showed a distinct diurnal variation and local formation of PAN was apparent. Whereas, in winter PAN concentrations showed little diurnal variation and there was little difference between concentrations at Mt. Teine and surface concentrations in Sapporo, which indicate wintertime PAN in Sapporo were not formed by local photochemistry. Regional scale three-dimensional transport/chemistry simulations were performed for the period February 1999, The model results were compared to measured concentration and PAN levels were found to be influenced by continental outflow of air pollutants., Japan Society of Civil Engineers

Chemical Analysis and Estimation of Optical Properties of Siberian Arctic Aerosols
AKIMOTO Shinsuke, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 8, 301, 306, 2000
Chemical properties measurements of aerosols were made over a few years in Tiksi, Norilisk and Yakutsk, Siberia. Results at Tiksi indicate a strong seasonal variation, high concentration in late winter to early spring and low value in summer, and that the major component of aerosols is sulfate. These results suggest that Siberian Arctic have been also poluted by Arctic Haze as well as other Arctic region. Optical properties of Siberian Arctic Haze were calculated using scattering theory of Mie. And also upward radiative flux from the top of atmosphere was estimated based on the optical properties. Furthermore, possibility of application of infrared remote sensing to Arctic haze was discussed., Japan Society of Civil Engineers

MEASUREMENTS OF OPTICAL PROPERTIES OF ATMOSPHERIC AEROSOLS OVER THE WESTERN PACIFIC OCEAN
UEDA Atsushi, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, ENDOH Tatsuo, Doboku Gakkai Ronbunshuu G, 8, 307, 311, 2000
Two research cruises were conducted in the western Pacific Ocean on board the R/V Mirai in winter and summer, 1999. Optical properties of atmospheric aerosols were observed, and the chemical components were analyzed. In winter cruise, in the region from 20° N to 32° N, scattering coefficient and absorption coefficient were as high as those observed in Sapporo. The concentrations of SO<SUB>4</SUB><SUP>2-</SUP>, NH<SUB>4</SUB><SUP>+</SUP> and elemental carbon (EC) were high, and Al was detected in the same region, which represents the existence of soil dust. Therefore, the aerosols in this region seem to be transported from land. In summer cruise, even in the region more than 1, 000km far from land, the aerosols had the chemical species derived from land. On the other hand, in other regions in the two cruises, scattering coefficient σ<SUB>sca</SUB> ranged from 10 to 20×10<SUP>-6</SUP> (m<SUP>-1</SUP>), and single scattering albedo ε was more than 0.98. These results suggest that the aerosols observed in the regions had much scattering properties, and little absorptive components such as EC., Japan Society of Civil Engineers

衛星リモートセンシングのための放射伝達モデルの開発
小林 拓, 太田 幸雄, 村尾 直人, 橘 治国, 山形 定, 衛生工学シンポジウム論文集, 7, 85, 90, 01 Nov. 1999
第7回衛生工学シンポジウム（平成11年11月11日（木）-12日（金） 北海道大学学術交流会館） . 3 地球環境 . 3-3, 北海道大学衛生工学会, Japanese

AAMP98観測北極圏上空エアロゾルの鉛直分布
庄司 和弘, 山形 定, 村尾 直人, 太田 幸雄, 塩原 匡貴, 藤井 理行, 衛生工学シンポジウム論文集, 7, 96, 101, 01 Nov. 1999
第7回衛生工学シンポジウム（平成11年11月11日（木）-12日（金） 北海道大学学術交流会館） . 3 地球環境 . P3-5, 北海道大学衛生工学会, Japanese

観測船「みらい」による海洋上エアロゾルの光学特性観測
上田 厚志, 太田 幸雄, 村尾 直人, 山形 定, 遠藤 辰雄, 衛生工学シンポジウム論文集, 7, 91, 95, 01 Nov. 1999
第7回衛生工学シンポジウム（平成11年11月11日（木）-12日（金） 北海道大学学術交流会館） . 3 地球環境 . 3-4, 北海道大学衛生工学会, Japanese

(大気エアロゾルのキャラクタリゼーション及び光学特性推定法に関する研究)(2.1プロジェクト研究)([2]共同利用研究(平成10年度))
太田 幸雄, 村尾 直人, 山形 定, 池内 和泉, 千葉大学環境リモートセンシング研究センター年報, 4, 21, 21, Oct. 1999
千葉大学, Japanese

1H12 OPTICAL PROPERTIES OF MARITIME AEROSOL AROUND OKINAWA
Ikeuchi I, Ohta S, Murao N, Kinjyo Y, Murano K, 大気環境学会年会講演要旨集, 40, 422, 422, 28 Sep. 1999
Japan Society for Atmospheric Environment, Japanese

1H21 Variation of PAN concentration in Sapporo (1) : Relationship with aldehyde
IKEYA Y, TSUZAKI M, MURAO N, YAMAGATA S, OHTA S, 大気環境学会年会講演要旨集, 40, 431, 431, 28 Sep. 1999
社団法人大気環境学会, Japanese

2C10 Measurement of the deposition flux of small-sized water droplets with a polymeric water absorbent(2nd report)
Izumi K, Utiyama M, Fukuyama T, Yamagata S, Ohta S, 大気環境学会年会講演要旨集, 40, 493, 493, 28 Sep. 1999
Japan Society for Atmospheric Environment, Japanese

2I06 Measurements of VOCs using TCT-GC/MS in Hokkaido
KATO H, MURAO N, OHTA S, YAMAGATA S, FUKASAWA T, 大気環境学会年会講演要旨集, 40, 533, 533, 28 Sep. 1999
社団法人大気環境学会, Japanese

2L05 The Size Distribution Masurement of Atmospheric Aerosol Chemical species
OHTA S, TAKEUCHI K, HASEGAWA S, MURAO N, YAMAGATA N, 大気環境学会年会講演要旨集, 40, 550, 550, 28 Sep. 1999
社団法人大気環境学会, Japanese

3H04 Measurements of optical properties of maritime aerosols on hte ship of Mirai
UEDA A, OHTA S, MURAO N, YAMAGATA S, 大気環境学会年会講演要旨集, 40, 586, 586, 28 Sep. 1999
社団法人大気環境学会, Japanese

3H08 Measurement of Atmospheric Pollution in the Siberian Arctic
ENOMOTO K, OHTA S, FUKASAWA T, MURAO N, YAMAGATA S, 大気環境学会年会講演要旨集, 40, 28 Sep. 1999
Japan Society for Atmospheric Environment, Japanese

Measurement of the deposition amount of small-sized water droplets with a polymeric water absorbent(2)
IZUMI Katsuyuki, UTIYAMA Masahiro, FUKUYAMA Tsutomu, YAMAGATA Sadamu, OHTA Sachio, エアロゾル科学・技術研究討論会 = Symposium on Aerosol Science & Technology, 16, 133, 135, 01 Jul. 1999
Japanese

立杭を用いた雲物理実験装置内で発生した雲の微物理過程(その5)-雲粒粒径分布に影響するパラメータ
佐々木 聰, 播磨屋 敏生, 藤吉 康志, 山形 定, 福山 力, 山田 正, 稲毛 正昭, 大会講演予講集, 75, B106, Apr. 1999
Japanese

The Concentrations of Reduced Sulfur Compounds in Urban Atmosphere and the Emissions of these Compounds from Sewage Treatment Facilities.
ITOHA Akiyoshi, MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 36, 81, 86, 1999
A method for the field sampling of reduced sulfur compounds such as carbonyl sulfide (COS) and carbon disulfide (CS<SUB>2</SUB>) was developed and applied to sewage treatment facility. This method has-100% trapping efficiency and more than 90% recovery and shows little loss for at least 24 hr storage for these sulfur compounds. Ambient concentrations of COS and CS<SUB>2</SUB> were measured at Sapporo from Oct. 1997 to Feb. 1999. During this periods COS and CS<SUB>2</SUB> concentrations were typically 528 ± 77pptv (parts per trillion by volume) and 46 ± 30pptv, respectively, andoccasional high COS concentrations up to 800pptv were observed, indicating the presence of COS source in urban area.The COS concentrations of exhaust from the sewage treatment facility were several times higher than ambient concentrations, while CS<SUB>2</SUB> values were larger than ambient by an order of magnitude. Estimated COS and CS<SUB>2</SUB> emissions based on this results, however, suggested that sewage treatment works were minor source of COS and CS<SUB>2</SUB>., Japan Society of Civil Engineers, Japanese

WINTERTIME VARIATION OF PEROXYACETYL NITRATE IN SAPPORO JAPAN
TSUZAKI Masaharu, MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 7, 207, 212, 1999
Peroxyacetyl Nitrate (PAN), measurement were made during the winter 1999 at Mt. Teine (1000m altitude) in Sapporo. Median concentration during February was 0.21ppb. Higher concentration >1.0ppb were sometimes observed with southerly wind and higher ozone concentrations. There was little difference between PAN concentration at Mt. Teine and surface concentration in Sapporo, which indicate wintertime PAN in Sapporo was not formed by local photochemistry. Results from concurrent measurements of aldehydes and ozone also indicate that variation of PAN during winter in Sapporo was regional in nature. From the results, we conclude at least during winter surface PAN measurement in Sapporo is a good indicator of photochemical state and long-range transport of polluted air mass in East Asia., Japan Society of Civil Engineers

Measurements of Atmospheric Pollution in the Siberian Arctic.
OHTA Sachio, ENOMOTO Kyoichi, FUKASAWA Tatsuya, MURAO Naoto, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 7, 231, 236, 1999
Atmospheric concentrations of aerosol chemical species and SO2 have been measured at Tiksi, Yakutsk and Norilsk in Siberia from 1993. Concentrations of SO4<SUP>2-</SUP>, Pb, Cu, Ni and V at Tiksi increase in winter and spring, and decrease in summer. Soil, moss and larch leaf samples were collected at Norilsk and Yakutsk, and soil samples at Tiksi. Concentrations of SO4<SUP>2-</SUP>, Ni and Cu in the moss and larch leaf samples decreased with the distance from nickel and copper smelters in Norilsk. Moss and larch leaf, thus, can be used as bio-monitor of the air pollution. Concentrations of pollutants in the surface soil were higer than those in the soil 20-30cm below in Norilsk and Tiksi. It suggests that the long range transported atmospheric pollutants deposit on the surface and accumulate in the upper layer of permafrost in the Siberian Arctic., Japan Society of Civil Engineers

TCT-GC/MSを用いた北海道における大気中VOCsの測定
加藤 秀樹, 山形 定, 村尾 直人, 太田 幸雄, 深沢 達矢, 衛生工学シンポジウム論文集, 6, 194, 199, 01 Nov. 1998
第6回衛生工学シンポジウム（平成10年11月5日（木）-6日（金） 北海道大学学術交流会館） . 5 測定・解析 . P5-10, 北海道大学衛生工学会, Japanese

AAMP98観測 北極圏上空エアロゾル中のイオン成分
庄司 和弘, 山形 定, 村尾 直人, 太田 幸雄, 塩原 匡貴, 藤井 理行, 衛生工学シンポジウム論文集, 6, 286, 291, 01 Nov. 1998
第6回衛生工学シンポジウム（平成10年11月5日（木）-6日（金） 北海道大学学術交流会館） . 7 調査事例 . P7-10, 北海道大学衛生工学会, Japanese

1E1300 Measurement of Peroxyacetyl Nitrate in Sapporo
Tsuzaki M, Murao N, Ohta S, Yamagata S, 大気環境学会年会講演要旨集, 39, 257, 257, 24 Sep. 1998
社団法人大気環境学会, Japanese

1F1300 Measurement of critical super saturation for the lower carboxilic acid aerosols
Hori M, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 39, 271, 271, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

1F1315 Large scale cloud chemistry experiment in shaft (part3)
Zaima T, Kuroda T, Yamagata S, Murao N, Ohta S, Harimaya T, Fuziyoshi Y, Izumi K, Yamada T, Uchiyama M, Fukuyama T, 大気環境学会年会講演要旨集, 39, 272, 272, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

1J1345 Emission of reduced sulfur compounds from urban area
Itoh A, Murao N, Ohta S, Yamagata S, 大気環境学会年会講演要旨集, 39, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

2A1100 Measurement of the deposition amount of small-sized water droplets with a polymeric water absorbent
Izumi K, Utiyama M, Fukuyama T, Yamagata S, Ohta S, 大気環境学会年会講演要旨集, 39, 323, 323, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

2E1130 AAMP98-Ionic components in the atmospheric aerosol over the Arctic region
Shoji K, Yamagata S, Murao N, Ohta S, Shiobara M, Fujii Y, 大気環境学会年会講演要旨集, 39, 359, 359, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

2H1115 Analysis of heavy metals concentration in leaves and soil by ICP-MS
Tamai N, Ohta S, Murao N, Yamagata S, Fukazawa T, Enomoto K, 大気環境学会年会講演要旨集, 39, 393, 393, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

3E1215 INVESTIGATION OF OPTICAL PROPERTIES OF ATMOSPHERIC AEROSOLS BASED ON SOLAR RADIATION MEASUREMENT AND CHEMICAL CHARACTERIZATION
Hasegawa S, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 39, 24 Sep. 1998
社団法人大気環境学会, Japanese

3H1015 Measurement of ambient VOCs in Hokkaido using TCT/GC-MS system
Kato H, Murao N, Ohta S, Yamagata S, Fukazawa T, 大気環境学会年会講演要旨集, 39, 500, 500, 24 Sep. 1998
社団法人大気環境学会, Japanese

3J0915 High sensitivity analysis of carbon in aerosols
Ueda A, Ohta S, Murao N, Yamagata S, 大気環境学会年会講演要旨集, 39, 511, 511, 24 Sep. 1998
社団法人大気環境学会, Japanese

3J0930 Measurements of dicarbonate aerosol using ionchromatography
Akimoto S, Ohta S, Murao N, Yamagata S, Hori M, 大気環境学会年会講演要旨集, 39, 512, 512, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

3J1030 Chemical characterization of the components of atmospheric aerosol by TG-MS
Arita M, Yamagata S, Hori M, Murao N, Ohta S, 大気環境学会年会講演要旨集, 39, 516, 516, 24 Sep. 1998
Japan Society for Atmospheric Environment, Japanese

Fluctuation of Cloud Droplet Concentration on Introduction of CN
UTIYAMA Masahiro, FUKUYAMA Tsutomu, IZUMI Katsuyuki, YAMAGATA Sadamu, OHTA Sachio, エアロゾル科学・技術研究討論会 = Symposium on Aerosol Science & Technology, 15, 186, 188, Aug. 1998
Japanese

Measurement of the deposition amount of small-sized water droplets with a polymeric water absorbent
IZUMI Katsuyuki, UTIYAMA Masahiro, FUKUYAMA Tsutomu, YAMAGATA Sadamu, OHTA Sachio, エアロゾル科学・技術研究討論会 = Symposium on Aerosol Science & Technology, 15, 189, 191, Aug. 1998
Japanese

Observations of Stratospheric and Tropospheric Particle Number Concentration between Mid-latitude and North Pole
WATANABE Masaharu, IWASAKA Yasunobu, SHIBATA Takashi, NAGATANI Masahiro, NAKADA Hiroshi, OSADA Kazuo, INOMATA Yayoi, ADACHI Hiroshi, HAYASHI Masahiko, TUCHIYA Masayoshi, SHIOBARA Masataka, YAMAGATA Sadamu, OOHASHI Toshitsugu, エアロゾル科学・技術研究討論会 = Symposium on Aerosol Science & Technology, 15, 256, 258, Aug. 1998
Japanese

Automatic Measurement of Peroxyacetyl Nitrate in Sapporo Japan.
TSUZAKI Masaharu, MURAO Naoto, OHTA Satio, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 35, 199, 204, 1998
An automated measurement system is developed to monitor Peroxyacetyl Nitrate (PAN). This systemis made of an automatic valve device and a gas chromatograph with a <SUP>63</SUP>Ni electron capture detector. A 5ml airsample is directly introduced in the gas chromatograph without any focusing process. Continuous measurements of PAN concentration were made in Sapporo from July 1997 to April 1998. Medianconcentration of PAN for each month show seasonal variation with a maximum of 0.37ppb in spring. Thisvariation resembles background PAN variation measured in England. However on warm sunny days in summer, PAN showed a distinct diurnal variation and local formation of PAN was apparent. Whereas, in spring andwinter, PAN concentration showed little diurnal variation. Moreover monthly maximum concentration in springwas as high as that in summer. During winter and spring, it is so cold in Sapporo that PAN production in theurban atmosphere is rather limited. Thus variation of PAN concentration during winter and spring is affectedby large scale air pollution., Japan Society of Civil Engineers, Japanese

Effect of water soluble aerosols acting as cloud condensation nuclei on the global warming
HORI Masahiro, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 6, 103, 108, 1998
To estimate indirect radiative forcing of water soluble aerosols, we measured critical supersaturations of dicarboxylic acid aerosols which are major components of water soluble organic aerosols in laboratory experiments, and then calculated albedo of marine stratiform cloud and downward net flux at tropopause within stratiform cloud area under clean and polluted (concentrations of water soluble aerosols enhanced) conditions. Experimental results indicated that critical supersaturations of oxalate, malic acid and phtharic acid were found to be comparable to that of sulfate aerosol which is easily activated to cloud droplets at naturally occuring supersaturations in the atmosphere, in contrast to high critical supersaturation of adipic acid. Caluculations indicated that at polluted condition cloud-top albedo was enhanced and downward net flux at tropopause decreased by 40-60W/m<SUP>2</SUP> from clean condition. Although these estimates are confined within polluted and stratus cloud aera, the indirect forcing is so high compared with global averaged radiative forcing (+2.5W/m<SUP>2</SUP>) of greenhouse gases, that it is possible that the forcing offsets the greenhouse effect to a large extent., Japan Society of Civil Engineers

INVESTIGATION OF OPTICAL PROPERTIES OF ATMOSPHERIC AEROSOLS BASED ON SOLAR RADIATION MEASUREMENT AND CHEMICAL CHARACTERIZATON
HASEGAWA Shuichi, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 6, 109, 114, 1998
Mixing condition and size distribution of atmospheric aerosols were investigated for determination of suitable optical aerosol model. If the geometric number mean radius and the standard deviation were 0.055-0.079μm and 1.97-2.29 in internal mixing condition respectively, calculated values of the ratio of diffuse solar radiation to direct solar radiation correlated well with those observed. Whereas the geometric number mean radius of 0.035 μm and standard deviation of 2.10, which have been recommended, gave less correlation. The difference of calculated single scattering albedo between external and internal mixture was 0.03, which has the possibility of the difference of 0.15°C of the global mean surface temperature., Japan Society of Civil Engineers

EMISSION OF REDUCED SULFUR COMPOUNDS FROM URBAN AREA
ITOH Akiyoshi, MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 6, 115, 119, 1998
A simple method for the field sampling of reduced sulfur compounds was developed and evaluated. This method has-100% trapping efficiency and more than 90% of recovery and shows little loss for 24hr storage for both carbonyl sulfide (COS) and carbon disulfide (CS<SUB>2</SUB>). Using this method, ambient concentrations of COS and CS<SUB>2</SUB> and emissions from sewage treatment plant and municiple landfill sanitary sites (M. L. S) were measured.The result shows that (1) COS and CS<SUB>2</SUB> concentrations were typically 515±87ppty (parts per trillion by volume) and 44±16pptv, respectively and showed little diurnal variation. However Increase of COS level sometimes occured, indicating emission of COS from urban area.(2) Exhaust from sewage treatment plant and M. L. S. contained more COS and CS<SUB>2</SUB> than ambient concentrations. From this, annual emissions of COS and CS<SUB>2</SUB> were estimated., Japan Society of Civil Engineers

AEROSOL OBSERVATIONS IN THE SIBERIAN ARCTIC
FUKASAWA Tatsuya, OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, MAKAROV Vladimir N., Proceedings of the NIPR Symposium on Polar Meteorology and Glaciology, 11, 150, 160, Nov. 1997
Atmospheric concentrations of total particulate mass (TPM) and aerosol chemical species were measured at three sites in the Siberian Arctic; Tiksi, Norilsk and Yakutsk. Continuous samplings of aerosols were carried out from August 1993 in Norilsk and Yakutsk, and from August 1994 in Tiksi. Tiksi is located on the coast of the Laptev Sea connecting to the Arctic Ocean. Norilsk is located at the base of the Taimyr Peninsula, which is the largest single sulfur dioxide emission source in the world. Yakutsk is situated on the middle reaches of the Lena river. Measured concentrations of the main aerosol chemical species at Tiksi ranged from 0.06-0.3μ(gm)^<-3> for elemental carbon, 0.55-1.5μ(gm)^<-3> for organic carbon and 0.09-1.6μ(gm)^<-3> for SO_4^<2->. The measured sulfate and elemental carbon concentrations showed remarkable seasonal variations with winter maxima and summer minima. The seasonal variations were consistent with other studies of Arctic haze in the Alaskan, Canadian and Norwegian Arctic. There were no significant seasonal variations of pollutant concentrations at Norilsk and Yakutsk. The TPM ranged from 6 to 30μ(gm)^<-3> at Norilsk and from 7 to 39μ(gm)^<-3> at Yakutsk. Major aerosol composition was sulfate at Norilsk, and carbonaceous particles at Yakutsk. We also performed trajectory analyses of air parcels to estimate the potential source regions which caused elevation of pollutant concentrations in winter at Tiksi. We calculated 10-day backward trajectories at Tiksi and forward trajectories at Norilsk in 1994. According to the calculations, the pollutants which arrived at Tiksi were frequently transported from Norilsk, the Urals and other source areas in winter. Further, it was suggested that Norilsk was one of the source areas for Arctic haze., National Institute of Polar Research, English

エアロゾルと気候影響-日本地域の大気混濁度の変動-
長谷川 就一, 深沢 達矢, 太田 幸雄, 村尾 直人, 山形 定, 衛生工学シンポジウム論文集, 5, 95, 100, 01 Nov. 1997
第5回衛生工学シンポジウム（平成9年11月6日（木）-7日（金） 北海道大学学術交流会館） . 2 評価・モデル . P2-9, 北海道大学衛生工学会, Japanese

水溶性有機エアロゾルの雲核特性評価実験
堀 雅裕, 太田 幸雄, 村尾 直人, 山形 定, 大会講演予講集, 72, P104, Oct. 1997
Japanese

Fluctuation of droplet size and base of cloud generated with semi-real scale
UTIYAMA M, FUKUYAMA T, TAKEUCHI N, YAMAGATA S, OHTA S, HARIMAYA T, SASAKI A, TANONAK T, OJIMA K, YAMADA T, INAGE M, エアロゾル科学・技術研究討論会 = Symposium on Aerosol Science & Technology, 14, 33, 35, Aug. 1997
Japanese

Acceleration of Sulfite Photooxidation by Seven Kinds of Soil Particles
YAMAGATA Sadamu, NISHIO Akiko, OHTA Sachio, HARA Hiroshi, 大気環境学会誌 = Journal of Japan Society for Atmospheric Environment, 32, 1, 68, 72, 10 Jan. 1997
Seven kinds of soil particles (3 mg) were dispersed in 20 ml of NaHSO₃ (1 mmoll^-1) solution and photoirradiated to investigate their effects on the photooxidation of S (IV). All seven soil particles catalyzed S (IV) oxidation without light. With photoirradiation, six soil particles accelerated the oxidation with oxidation rate ranging from 0.5-2.3×10^-5 moll^-1 min^-1, compared to 0.3-1.5×10^-5 moll^-1 min^-1 without photoirradiation. Fe concentration increased during the oxidation of S (IV)., Japan Society for Atmospheric Environment, Japanese

Acceleration of Sulfite photooxidation by Seven Kinds of Soil Particles
YAMAGATA Sadamu, NISHIO Akiko, OHTA Sachio, HARA Hiroshi, Journal of Japan Society for Atmospheric Environment, 32, 1, 68, 72, 10 Jan. 1997
Seven kinds of soil particles (3mg) were dispersed in 20ml of NaHSO_3 (1 mmoll^<-1>) solution and photoirradiated to investigate their effects on the photooxidation of S (IV). All seven soil particles catalyzed S (IV) oxidation without light. With photoirradiation, six soil particles accelerated the oxidation with oxidation rate ranging from 0.5-2.3×10^<-5> moll^<-1> min^<-1>, compared to 0.3-1.5×10^<-5> moll^<-1> min^<-1> without photoirradiation. Fe concentration increased during the oxidation of S (IV)., 公益社団法人大気環境学会, Japanese

Acceleration of Sulfite Photooxidation by Seven Kinds of Soil Particles.
YAMAGATA Sadamu, NISHIO Akiko, OHTA Sachio, HARA Hiroshi, Journal of Japan Society of Air Pollution, 32, 1, 68, 72, 1997
Seven kinds of soil particles (3 mg) were dispersed in 20 m<I>l</I> of NaHSO<SUB>3</SUB> (1 mmoll<SUP>-1</SUP>) solution and photoirradiated to investigate their effects on the photooxidation of S (IV). All seven soil particles catalyzed S (IV) oxidation without light. With photoirradiation, six soil particles accelerated the oxidation with oxidation rate ranging from 0.5-2.3×10<SUP>-5</SUP> moll<SUP>-1</SUP> min<SUP>-1</SUP>, compared to 0.3-1.5×10<SUP>-5</SUP> moll<SUP>-1</SUP> min<SUP>-1</SUP> without photoirradiation. Fe concentration increased during the oxidation of S (IV)., Japan Society for Atmospheric Environment, Japanese

衛星リモートセンシングによる沿岸海域汚濁解析 : 赤潮プランクトン濃度推定について
小林 拓, 太田 幸雄, 村尾 直人, 橘 治国, 山形 定, 衛生工学シンポジウム論文集, 4, 219, 224, 01 Nov. 1996
第4回衛生工学シンポジウム（平成8年11月7日（木）-8日（金） 北海道大学学術交流会館） . 5 測定 . P5-8, 北海道大学衛生工学会, Japanese

CHEMICAL AND OPTICAL PROPERTIES OF LOWER TROPOSPHERIC AEROSOLS MEASURED AT Mt. LEMMON IN ARIZONA
OHTA Sachio, HORI Masahiro, MURAO Naoto, YAMAGATA Sadamu, GAST Karl, J. Global Environment Engineering, 2, 67, 78, 01 Mar. 1996
English

ESTIMATION OF RED TIDES ALGAE CONCENTRATION BY SATELLITE REMOTE SENSING
KOBAYASHI Hiroshi, OHTA Sachio, MURAO Naoto, TACHIBANA Harukuni, YAMAGATA Sadamu, Doboku Gakkai Ronbunshuu G, 33, 85, 93, 1996
For satellite remote sensing of red tides, a radiative transfer model for a coupled atmosphere-ocean system was developed to estimate upward flux of radiation from the polluted sea surface.Size distribution and the complex index of refraction of two kinds of red tide algae (<I>Skeletonema costatum and Heterosigma akashiwo</I>) were measured in batch cultures. The equation of radiative transfer in the coupled atmosphere-ocean system was solved by using Delta-P3 approximation method.Upward flux of radiation from the polluted sea surface which contained only the red tide algae decreased with the inclease of algae concentration.Whereas, in case of the sea which contained detritus in addition to the red tide algae, the upward flux had a peak at the wavelength of yellow region.It is, thus, important to determine the concentration and optical properties of detritus for the red tide remote sensing.Ratio of the upward flux at the wavelength of 410nm to one at 560nm decreased with the algae concentration.It is, then, possible to determine the red tide algae concentration by using the ratio of upward flux in satellite remote sensing., Japan Society of Civil Engineers

雲を観る
山形 定, 荻原 研二, 住吉 力, 太田 幸雄, 村尾 直人, 山田 正, 藤吉 康志, 播磨屋 敏生, 福山 力, 内山 政弘, 稲毛 正昭, 衛生工学シンポジウム論文集, 3, 208, 213, 01 Nov. 1995
第3回衛生工学シンポジウム（平成7年11月9日（木）-10日（金） 北海道大学学術交流会館） . 4 都市・水・室内等の環境 . P4-7, 北海道大学衛生工学会, Japanese

シベリア北極海沿岸ティクシにおけるガス・エアロゾル濃度観測
深澤 達矢, 太田 幸雄, 村尾 直人, 山形 定, 大会講演予講集, 68, 219, 219, 16 Oct. 1995
Japanese

Variation of Atmospheric Turbidity in Japanese Area.
OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, FUKASAWA Tatsuya, SUMIYOSHI Tsutomu, ARAO Kimio, Doboku Gakkai Ronbunshuu G, 32, 231, 239, 1995
Atmospheric turbidity coefficients were calculated at five sites (Nemuro, Sapporo, Shionomisaki, Tosa-Shimizu and Ishigaki) in Japanese area from 1980 through 1992. The turbidity coefficients ranged 0.03-0.30 at Nemuro, 0.05-0.40 at Sapporo, 0.05-0.45 at Shionomisaki, 0.03-0.40 at Tosa-Shimizu and 0.03-0.40 at Ishigaki. They decreased in autumn and winter, and increased in spring. Variations of the turbidity coefficients had tendency of increase from 1957 through 1992 due to increase of human activities. In 1982-1984 and after 1992, the turbidity coefficients had the maximum due to large volcanic eruptions of Mt. El Chichon and Mt. Pinatubo, respectively., Japan Society of Civil Engineers, Japanese

A Simple Method for Parameterization of Tropospheric Photochemistry Based on Sensitivity Analysis.
Murao Naoto, Nakayama Satomi, Ohta Satio, Yamagata Sadamu, Mizoguchi Isao, Doboku Gakkai Ronbunshuu G, 31, 241, 250, 1994
In order to construct useful transport-chemistry model for large-scale variations of tropospheric trace species, accurate and low computational cost submodel for reaction is needed. Based on sensitivity analysis, Dunker developed a simple method for parameterization of atmospheric chemistry. We have investigated the possibility of applying the method to the equations of tropospheric photochemistry. Since the method was developed for urban air chemistry, some modifications were made. One-dimensional tropospheric model was used to test its accuracy and computational speed. The results indicated little loss of accuracy compared to detailed model simulations of chemistry with high time resolution. In addition, the computation time was reduced by about 2-order of magnitude., Japan Society of Civil Engineers, Japanese

Albedo effect of anthropogenic arctic aerosols on climate.
OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, HAYASHI Kentaro, ISHIHARA Hironari, Doboku Gakkai Ronbunshuu G, 31, 251, 262, 1994
Albedo effect of anthropogenic Arctic aerosols on climate was estimated through planetary albedo calculation and surface temperature evaluation with two-layer zonal energy balance climate model. Six types of global aerosol models were assumed in the atmospheric boundary layer: Arctic aerosols, subarctic aerosols, continental aerosols, maritime aerosols in Northern Hemisphere, maritime aerosols in Southern Hemisphere and Antarctic aerosols. Optical properties of each type of aerosols were calculated based on chemical characterization. Internal mixing aerosols seriously affect on climate in Arctic Circle. Doubling anthropogenic Arctic aerosols causes 0.3°C increase of surface temperature, whereas the disappearance causes 0.15°C decrease of surface temperature in Arctic Circle., Japan Society of Civil Engineers, Japanese

大気環境をはかる
溝口 勲, 太田 幸雄, 村尾 直人, 山形 定, 衛生工学シンポジウム論文集, 1, 385, 389, 01 Nov. 1993
第1回衛生工学シンポジウム（平成5年11月17日（水）-18日（木） 北海道大学学術交流会館） . パネルディスカッション . 環境をはかる, 北海道大学衛生工学会, Japanese

Health effect evaluation and measures planning of PM2.5 using sensor technology
Grants-in-Aid for Scientific Research
01 Apr. 2016 - 31 Mar. 2019
Murao Naoto
This study works on development, practical use of a small personal exposure measuring equipment and establishment of the new evaluation technique for the long-range transported pollution ratio based on the measurement.
(1) A new approach to evaluate transboundary PM pollution is applied to Tama-kyuryo, Kazo and Nagasaki city. The results suggest that transboundary pollution contributed more than 70% to the PM2.5 concentrations, and that the ontribution has a seasonal variation with a decrease in summer and an increase in autumn.
(2) The sensor system developed and used in the field test is a particle counter with a volume of 768 cm3, a weight of 420 g, and over 24 h of continuous operation. Using the sensor, personal exposure in winter were characterized for 5 subjects living in Sapporo area. Ambient PM2.5 data measured at fixed stations were used as a comparison against the personal PM2.5 exposures and produced poor correlations between personal and ambient PM2.5.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 16K06551

Development of ozone sensor for environmental monitoring and its application to ozone pollution with various scale
Grants-in-Aid for Scientific Research
01 Apr. 2013 - 31 Mar. 2016
MURAO NAOTO, YAMAGATA Sadamu, FUKASAWA Tatsuya, YAMAGUCHI Takashi
This study try to put portable and affordable ozone sensor to practical use.
In a study period of 3 years, toward the practical realization of the ozone sensor, we conducted studies for 1) identification of environmental conditions affecting the sensor response, and establishment of a calibration method, 2) development of monitoring data transmission system, and 3) application of ozone sensor to environmental measurement in a distant area and a forest area.
As a result, it was shown that automatic and unmanned environmental monitoring with the sensors is possible when the sensor is calibrated for the seasonal variation of ambient temperature, and this sensor can greatly contribute to forest impact evaluation of ozone.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 25340001

The climate effects by the change of the short-lived atmospheric fine particles with pollution-abatement measures in China
Grants-in-Aid for Scientific Research
2009 - 2011
MURAO Naoto, YAMAGATA Sadamu
To clarify how air pollution/global warming measures taken in China change the distribution of atmospheric particles and meteorological field, measurements and model calculations were made for three years. From the measurements made at Sapporo, Fukue island and Cape Hedo, we identified seasonal source areas that impact the particles concentration at each site. Based on these data, we estimated the climate effects of Asian aerosols using a regional meteorological model.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 21560567

Development of the system to disclose the spatial distribution of aerosol absorption coefficients in real time
Grants-in-Aid for Scientific Research
2007 - 2009
YAMAGATA Sadamu
Techniques for high-precision measurement and automatic data retrieval were developed for the tape-filter type absorption photometer designed by the researcher to measure absorption coefficients of atmospheric aerosol particles. Five systems were installed in monitoring station in Sapporo city to observe the variation of absorption coefficients. They consist of two parts ; those transported from outside of the city and those emitted inside the city mainly from automobile. From the statistical back trajectory analysis it was suggested that absorption coefficients in Sapporo is influenced by the air mass transported from big cities and industrial areas in China and Korea.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 19510003

Research of Contaminated Aerosol Distribution by Artificial Satellite and Evaluation of the Aerosol Effect on Climate in the East Asia
Grants-in-Aid for Scientific Research
2005 - 2007
OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu
Atmospheric aerosols affect on climate due to scattering and absorption of solar radiation. In the East Asia, estimation of the climatic effect is significant because of recent industrial development. For the evaluation, we need the distribution of optical depth and optical properties (scattering and absorption coefficients) of aerosols. It is effective for determination of the optical depth distribution by using radiance analysis measured by artificial satellite, though the optical properties are necessary to the analysis. In the research we thus made measurement of the optical properties of atmospheric aerosols at Fukue island, Nagasaki prefecture in spring and summer. Single scattering albedo (scattering coefficient / (scattering coefficient + absorption coefficient)) of aerosols were 0.8〜0.9 and 0.9〜0.99 in summer and spring, respectively. Absorption coefficient measured by integrated sphere method had highly correlation with those by PSAP method. It is, further, practicable to determine the distribution of optical depth by artificial satellite analysis, if we assign the optical properties by using chemical characterization of aerosols. We made aerosol models based on the chemical analysis. Comparing the model calculation with the measured results, we concluded that the optimum aerosol model are made up of internal mixture and geometric number mean diameter of 0.05〜0.07μm in lognormal size distribution function.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 17360251

Study on the role of aerosols in polar atmosphere and aerosol-cloud interaction obtained by comparative airborne observations in the Arctic and Antarctic
Grants-in-Aid for Scientific Research
2004 - 2007
YAMANOUCHI Takashi, WADA Makoto, SHIOBARA Masataka, HIRASAWA Naohiko, MORIMOTO Shinji, HARA Keiichiro
Through airborne observations of aerosols in the Arctic and Antarctic, it was found that a long range transport was crucial to the variations of polar aerosols, and the behavior of black carbon, which has a large impact on climate, might be a matter of discussion in the near future. The major findings were as follows:
1. In May to June 2004, Arctic Study of Tropospheric Aerosol, Cloud and Radiation (ASTAR) 2004 was conducted using two airplanes under the cooperation with Alfred-Wegener Institute of Polar and Marine Research (AVM. Both the scattering coefficients and absorption coefficients obtained by airborne observations showed a lower value compared to those in the Arctic haze term, March to April, obtained in ASTAR 2000. Internal mixture of black carbon in the sulfur aerosol was predominant. Ground based observations showed a transition from spring to summer season with a wet deposition of aerosols by rain, suggesting aerosol-cloud interaction.
2. Japan-German Cooperative Airborne Atmosphere Observation (ANTSY0-II) was carried out using AWI Polar 2, during December 2006 and January 2007. Total of 22 flights were made around Neumayer Station and 15 flights including horizontal flights over the ocean and vertical profile flights over the ice were made around Syowa Station based at S17 point. 3-D distributions of physical, chemical and optical properties of aerosol were obtained, together with an air sampling for greenhouse gases. Atmospheric transports were rather common from Antarctic peninsula at Neumayer area, on the other hand, they were from the Atlantic and South America at Syowa area, and these transports characterized the aerosol properties. Some evidence of black carbon aerosols transported through inland was found. Ground based observations at Syowa Station and ship borne observations on board RV Umitaka Maru showed also some evidence of aerosols of marine biological origin.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), National Institute of Polar Research, 16253001

INDIRECT EFFECT OF AEROSOLS ON GLOVAL COOLING
Grants-in-Aid for Scientific Research
2002 - 2005
OHTA Sachio, MURAO Naoto, YAMAGATA Sadamu, SANO Itaru
For evaluation of indirect effects of aerosol particles on climate, field experiments, named with Magic Monkey Project (MMP), were carried out in Artificial Cloud Experimental System (ACES) established in an abandoned vertical shaft with 430m depth in Kamaishi Mining Co. in Iwate pref., Japan. The experiments evaluating the influence of the number concentration of (NH4)2SO4/NaC1 aerosol particles on the properties of resulting cloud droplets were performed in November every year from 2002 to 2005.
At the top of ACES there were two fans which made updraft inside ACES at the maximum 1.4[m/sec]. In the ACES any favorable altitude for measurement are accessible by ladders settled from the bottom to the top. Cloud droplets were visible around 30m above the bottom. Aerosol particles of ammonium sulfate and sodium chloride were generated at the bottom of ACES by atomizers into the air. According to the results obtained in the preliminary experiments intense measurements were carried out between the bottom and the altitude of 100m from there. Cloud droplets were sampled by impactors at several altitudes.
Inside ACES the temperature is very stable around 13.0 degree Celsius at the bottom. Temperature profiles in the ACES showed that temperature lapse rates were small around 30-50m above the bottom of ACES where cloud generation started. When aerosol particles, such as ammonium sulfate and sodium chloride, were generated at the bottom, the number concentration of cloud droplets increased and their diameter decreased keeping the amount of liquid water contents almost constant.
Among the parameters influenced to change the climate, the indirect effect of aerosol is the one with largest uncertainty. Although the results obtained here are envisioned to be used in a general circulation model (GCM), we can not use those result directly. The procedure to modify the obtained results for GCM model was also considered.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research on Priority Areas, HOKKAIDO UNIVERSITY, 14048201

Risk estimation from urban air pollution based on Diesel Exhaust Partide (DEP) measurement
Grants-in-Aid for Scientific Research
2003 - 2004
MURAO Naoto, OHTA Sachio, YAMAGATA Sadamu
Air pollution problems by suspended particulate matter (SPM) are still serious in metropolitan areas in Japan. Especially, health (carcinogenesis) risk from diesel exhaust particles (DEP) is considered to be significant. The purpose of this research is to (1)conduct long-term black carbon (major component of DEP) field measurements using a small absorption photometer developed by our group, (2)evaluate risks and source contributions using the measurement results, and (3)show how the introduction of the low-emission vehicle can reduce urban air pollution.
In 2003, after examining various measurement methods, we started measurements at ten air monitoring stations in Sapporo. The measured components are black carbon, volatile organic compounds, polynuclear aromatic hydrocarbons, heavy metals. In 2004, the measurements were continued, and an method of estimating DEP concentrations from the variations of various pollutants was examined.
The main findings are as follows.
(1)By using tape type absorption photometer, the high temporal variations of the black carbon were obtained.
(2)Black carbon showed a seasonal variation with a maximum in autumn, and a minimum in spring.
(3)From a statistical analysis and a diffusion calculation, the DEP contribution to SPM and black carbon content in DEP were estimated.
(4)Assuming the DEP unit risk (3.4x10^<-5>, WHO), the estimated carcinogenesis risk level in Sapporo ranged from 1.7x10^<-4> to 3.7x10^<-4>.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), HOKKAIDO UNIVERSITY, 15560468

北極域対流圏・成層圏物質の変動と気候影響
科学研究費助成事業
1999 - 2004
山内 恭, 和田 誠, 塩原 匡貴, 森本 真司, 青木 周司, 山形 定, 橋田 元, 遊馬 芳雄, 平沢 尚彦
北極域大気の対流圏、成層圏における温室効果気体やエアロゾル、オゾン、雲の変動を明らかにし、その原因となる輸送や生成・消滅/吸収過程の解明をはかり、南極域と対比しつつ、放射効果などを通じた気候への影響を評価することを目的としている。平成16年度は以下の結果を得た。
1.スバールバル諸島ニーオルスン基地における、温室効果気体についての大気サンプリング観測や、地上観測、オゾンの連続観測を継続した。気体濃度の分析として二酸化炭素、メタン、一酸化二窒素、酸素・窒素比、SF6濃度について実施し、さらに安定同位体比として二酸化炭素中の炭素同位体、酸素同位体、メタン中の炭素同位体比を求めた。特に酸素・窒素比から二酸化炭素収支のここ数年の様態が明らかにされた。
2.地上からのエアロゾル・雲のリモートセンシング観測として進めているマイクロパルスライダー観測に併せ全天カメラ観測を行い、雲の情報取得につとめた。レーダ観測は継続しエコー頂高度分布統計値の取得を進めた。
3.北極対流圏エアロゾル雲放射総合観測(ASTAR 2004)に参加した。ドイツ、アルフレッド・ウェーゲナー極地海洋研究所(AWI)の航空機2機を使って、5〜6月に実施したもので、多数の機関が参加した。インパクターの観測からは、先のASTAR2000とは異なる人為的汚染の少ない清浄なエアロゾル組成が明らかにされた。地上観測からは、北極ヘイズの時期が終了し、大気が清浄になる過程がとらえられている。
4.引き続きASTAR 2000(北極対流圏エアロゾル放射総合観測)およびAAMP 02(北極海横断航空機大気観測)の高次のデータ解析が進められ、エアロゾルの分布にクラスター解析を適用した結果や成層圏・対流圏物質交換の指標となる様々な物質の分布が導出された。
日本学術振興会, 特定領域研究, 国立極地研究所, 11208201

Measurement of chemical species in atmospheric aerosol with high time resolution by continuous
Grants-in-Aid for Scientific Research
2001 - 2003
YAMAGATA Sadamu
Absorption spectra of aerosol particles were continuously observed with developed instruments in Sapporo city. In downtown there are many aerosol particle sources including those emit elemental carbo. Because of high optical absorption coefficient of elemental carbon, it is not common for the observed absorption spectra to have specific structure. Near infrared region, however, is an exception where absorption spectra have shown different behavior from those in visible region.
Based on the result that absorption spectra are mainly contribution by elemental carbon instruments, Sampling photometer and absorption photometer with tape filter were developed and used at islands in East China Sea and Sapporo city, respectively. These instruments can automatically measure absorption coefficient for more than one month without filter exchange.
In Sapporo, the concentration level of elemental carbon depends on their locations while their tune variations are similar indicating that elemental carbon originates from the same source. The measurement with the Sampling Photometer at islands showed that filters used for absorption coefficient were further available to chemical analyses. At island, however, the measurements suffered serious troubles during summer with high temperature and relative humidity which caused condensation of water vapor on the filter. It is necessary to obtain daily data from instruments to maintain instruments continuously without any deficit of data.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 13680594

ANALYSIS OF ENVIRONMENTAL POLLUTION IN THE EAST ASIA BY SATELLITE REMOTE SENSING
Grants-in-Aid for Scientific Research
2000 - 2002
OHTA Sachio, YAMAGATA Sadamu, MURAO Naoto
The volume scattering coefficient, volume absorption coefficient, size distribution and chemical components of atmospheric aerosols were measured at Amami-Oshima and Fukue islands. In spring, atmospheric concentrations of air pollutants such as soot, sulfate and heavy metals increased as well as soil particles. According to back trajectory analysis, the large amounts of pollutants were transported with yellow sand from the Continental China to the western Pacific Ocean in the periods. The single scattering albedo ranged from 0.75 to 0.90 for fine particles.
Using above single scattering albedo, distribution of the aerosol optical depth, which shows the amount of aerosols in the atmosphere, was estimated in the East Asia with analysis of radiance data by MODIS sensor in artificial satellite Terra. Due to the analysis, in March 2001 in Suchowan area in sourth China there appeared more than 2.0 in optical depth which deried from air pollutants emitted at Chontsu city. And in April 2000 in Korea, large amounts of forest fire aerosols were transported from Chunian to the Sea of Japan. Thus the research enabled us to estimate the environmental pollution by satellite remote sensing.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), HOKKAIDO UNIVERSITY, 12450209

Anthropogenic Emissions of Reduced Sulfur Compounds from Municipal Landfill sanitary sites
Grants-in-Aid for Scientific Research
2000 - 2001
MURAO Naoto, YAMAGATA Sadamu, OHTA Sachio
The gaseous sulfur compounds which produce sulfate aerosols in the atmosphere play an important role in various global environmental problems. In particular, carbonyl sulfide (COS) influences the stratospheric ozone destruction and the global warming through formation of the stratospheric aerosols. However, its contribution is not evaluated enough. Moreover, the evaluation of anthropogenic emissions of COS and carbon disulfide (CS2) which is the precursor of COS is insufficient.
In this study, the contribution of COS to the formation of the stratospheric aerosols was reevaluated, and the emissions of reduced sulfur compounds from municipal landfill sanitary sites were measured. The main findings are as follows.
・The results from 1-D model calculation indicate that the contribution of COS to the formation of the stratospheric aerosols has been increasing due to the recent decrease of the stratospheric ozone concentration.
・The measurements of the landfill emissions of reduced sulfur compounds indicate that the landfill which contain biodegradable components emit large amount of reduced sulfur species. However, it was found that the landfill emission from industrialized nations contribute little to the global COS budget.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), HOKKAIDO UNIVERSITY, 12650540

Climatic imopact of aerosol,ozone and cloud in the Arctic
Grants-in-Aid for Scientific Research
1999 - 2001
YAMANOUCHI Takashi, ASUMA Yoshio, SHIOBARA Masataka, WADA Makoto, HARA Ei-ichiro, YAMAGATA Sadamu
The goal of the research project was to investigate the behavior, properties and radiative forcing of tropospheric aerosols in the Arctic with the special focus on the "Arctic Haze", and their interaction to cloud formation and surface ozone depletion (SOD). At the Ny-Alesund observatory (79 N, 12 S), in the international research site, following long term observation since 1992, a new observation system was installed to extend the research field to aerosol-cloud-radiation studies. For the purposes, remote sensing by sky radiometer, micro-pulse lidar and precipitation occurrence sensor system has been started together with originally maintained vertical pointing radar and microwave radiometer. Also, in-situ measurements by optical particle counter, integrating nepherometer and particle mobility analyzer have been made. Continuing the surface ozone measurement, SOD relation to the halogen chemistry and sea-salt modification was discussed. A new German-Japanese cooperative project on aerosols in the Arctic, "Arctic Study of Tropospheric Aerosol and Radiation (ASTAR 2000)", was conducted during 5 weeks in March and April, 2000, in the vicinity of Svalbard. Airborne observations of vertical distribution of physical, chemical and optical properties of aerosols were performed using Dornier 228 aircraft of AWI. Extinction coefficients were measured by sunphotometer. In-situ measurements and sampling of aerosols were also made. 19 flights with more than 80 flight hours were conducted based at Longyearbyen airport. Coordinated remote sensing and in-situ measurements at the surface at Ny-Alesund observatory were compared. Balloon-borne aerosol sondes were launched and tethered balloon was used. Data were also compared with SAGE-II satellite measurements. These data were used as input parameters for an Arctic regional climate model to calculate the radiative forcing of aerosols and study their climatic impact.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Natiomal Institute of Polar Research, 11691138

Study on the complex process between cloud physics and cloud chemistry related to global warming and acidification using quasi-real-scale artificial cloud
Grants-in-Aid for Scientific Research
1999 - 2001
HARIMAYA Toshio, YAMAGATA Sadamu, TAKAHASHI Tsuneya, MURAMOTO Ken-ichiro
Study on the process of cloud formation - The microphysical process of artificial cloud formation was studied using a quasi-real-scale cloud physics experimental system. This is the first study to show that aerosol is activated by an increase in relative humidity in air mass and that the activated aerosol grows to cloud droplet by condensation growth while the air mass is rising. This is also first study in which the effects of various parameter on the size distribution of cloud droplets have been quantified by actual measurements. Calculations on cloud droplet growth using a cloud model were carried out in stead of experiments in some cases. It enable to consider covering a wide parameter field about their influence parameters. In order to confirm that the experimental results accurately reflect that in the natural atmosphere, aerial observations were carried out to determine the relationship between aerosol number concentration under a cloud base and cloud droplet number concentration in a cloud.
Study on acid rain - The acidification mechanism on three formation processes of precipitation, namely, cloud droplet, rain drop and snow particle should be considered in order to understand the process by which acid rain is generated. First, the acidification of cloud droplets in sea fog was studied by observations carried out on a ship at sea. Next, oxidation experiments on sulfurous acid ions were carried out using a cloud physics experimental system with a long vertical mine shaft. The ions were oxidized during their passage up to the top of a vertical mine shaft of 430 m in height. The reaction speed was faster than that in an experiment using bulk solution in the laboratory. We also reviewed reports on gas scavenging by snow particles, as the mechanism by which snow particles are acidified is considered to be an important research subject.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), HOKKAIDO UNIVERSITY, 11304027

多成分粒子系エアロゾルモデルの放射特性の評価
科学研究費助成事業
2000 - 2000
太田 幸雄, 山形 定, 村尾 直人
札幌および長崎県五島列島福江島において、大気エアロゾルをテフロンフィルターおよび石英繊維フィルター上に捕集し、化学成分分析を行ってその組成解析を行った。さらに積分型散乱計および吸収光度計を用いて散乱係数および吸収係数の同時測定も行った。またインパクターを用いてエアロゾルを捕集し、電子顕微鏡解析を行い、引き続き水透析法を用いて電子顕微鏡解析を行うことにより、混合粒子の存在割合についても実態解析を行った。以上の観測結果より、大気エアロゾルを黒色純炭素、有機物、硫酸アンモニウム、硝酸アンモニウム、海塩および土壌粒子の6成分から成るものとし、さらに混合粒子の存在も仮定して、各成分粒子系に対して様々な粒径分布を与え、さらに混合状態として外部混合および内部混合状態を仮定して、ミー散乱理論に基づき散乱係数と吸収係数を算出した。算出された散乱係数および吸収係数と、同時に実測された測定値とを比較した結果、微小エアロゾルに対して、外部混合状態を仮定し、個数表示の対数正規分布形として幾何平均半径が0.046μm、幾何標準偏差が1.7の場合に、計算値と実測値が最も良く一致した。
以上のことから、多成分多分散粒子の集合体である大気エアロゾルに対して、光学的に最適のモデルとして、各成分粒子系を対数正規分布とし、黒色純炭素、有機物、硫酸アンモニウムおよび硝酸アンモニウムに対しては個数表示の幾何平均半径を0.046μm、幾何標準偏差を1.7、一方、海塩および土壌粒子に対しては幾何平均半径を0.49μm、幾何標準偏差を2.15とするモデルを選定した。
日本学術振興会, 特定領域研究(A), 北海道大学, 12018202

放射影響評価のための多成分粒子系エアロゾルモデルの構築
科学研究費助成事業
1999 - 1999
太田 幸雄, 山形 定, 村尾 直人
大気エアロゾルの地球温暖化抑制効果を定量的に評価するためには、地球上の様々な地域におけるエアロゾルの放射特性(粒径分布と複素屈折率、あるいは散乱係数と呼吸係数)の把握が不可欠である。本研究ではこれまで、エアロゾルを多成分粒子の集合体とみなし、ミー散乱理論計算によりエアロゾルの散乱・呼吸係数を算出する手法の開発を行なってきた。しかし本方法はあくまでも計算による方法であるので、本研究班では平成11年度に、札幌の北大工学部屋上において、4時間程度の短時間での大気エアロゾルのフィルター捕集と、積分型ネフェロメーターと吸収光度計を用いた散乱係数および呼吸係数の同時観測を行い、それらの測定値と、化学組成分析結果から算出された値との比較検討を行なった。
その結果、まず、各成分粒子系の粒系分布についてはこれまで本研究班によりカスケートインパクターなどを用いて測定してきた各成分粒子の粒径分布を与え、各成分粒子が各々独立に存在すると仮定した場合(外部混合状態)、および混合粒子(煤を核とし、その上に硫酸イオンあるいは有機物の殻をもった粒子)の存在割合が50%の場合(50%内部混合状態)について算出された体積散乱係数は、積分型ネフェーメータによる実測値の1.5〜2倍以内であることがわかった。一方、同様にして算出された体積呼吸係数は、粒径分布と混合粒子の存在割合によって^^+__-50%の違いを生じることがわかった。今後やはり特に混合粒子の実測が重要である。
日本学術振興会, 特定領域研究(A), 北海道大学, 11131202

Real Scale Experiment of Pollution and Modification of Cloud by using a Vertical Shaft.
Grants-in-Aid for Scientific Research
1997 - 1999
OHTA Sachio, FUKUYAMA Tsutomu, YAMAGATA Sadsamu, MURAO Naoto, UTIYAMA Masahiro
The process of sulfur dioxide dissolution into cloud droplets and its successive oxidation to sulfate were studied in an artificial cloud experimental system in a vertical shaft in Kamaishi mining company, Iwate prefecture. Sulfur compounds in droplets, aerosols and gas were collected by serial samplers at several heights. The concentrations of sulfur compounds at each height indicate that the released sulfur dioxide at the bottom of the shaft was absorbed by cloud droplets, but the oxidation rate to sulfate was slow which may be due to the absence of light and oxidants in the shaft.
Sodium chloride and sodium hydrogensulfite particles were generated by humifier and injected into the base of shaft. Modal diameter of the particles is 0.1〜0.5μm. Without the particle injection, modal diameter of cloud droplets was 7 μm. With the particle injection, modal diameter of cloud droplets did not change, but the size distribution widened out to larger diameter.
By using eletron microscope with X ray analyzer, we found that more than 50 % of the droplets, which arrived at top of the shaft, contained chemical species of the injected particles. But, the other particles cintained calsium carbonate. It shows that calsium carbonate particles or mineral particles coated with calsium carbonate on the surface may act as condensation nuclei in the atmosphere.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 09450195

Research on Air Pollution and Evaluation of the Environmental Effects in Siberian Wetland.
Grants-in-Aid for Scientific Research
1997 - 1999
OHTA Sachio, FUKASAWA Tatsuya, MURAO Naoto
Atmospheric concentrations of aerosol chemical species and gaseous pollutants such as sulfur dioxide, nitric oxide and nitrogen dioxide have been measured at Yakutsk, Tiksi and Norilsk in Siberia since 1994.
At Tiksi concentrations of elemental carbon, organic matter, sulfate and heavy metals as lead, copper, vanadium, nickel and arsenic increase in winter and spring. The results show occurance of the arctic haze also around Tiksi area.
At Norilsk, atmospheric concentration of sulfur dioxide is high as 260 ppbv, which is ten times more than that in Sapporo. Pine leaves, moss and surface soil around Norilsk contain much amount of sulfate and heavy metals as copper, nickel, cobalt and lead, which are derived from the nickel and copper smeltery in Norilsk city. The upper layer in the surface soil (active layer) contains higher concentrations of sulfate and heavy metals. By using the vertical profile of the pollutant concentration in soil, we calculated accumulation of the pollutants for these 30 years emitted from the smeltry in Norilsk city.
Ten days backward trajectory analysis shows that a large amount of air pollutants is transported from Ural industry and Norilsk area to Tiksi in winter.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B)., HOKKAIDO UNIVERSITY, 09041120

化学組成分析に基づく対流圏エアロゾルの放射特性の評価
科学研究費助成事業
1998 - 1998
太田 幸雄, 山形 定, 村尾 直人
これまで、対流圏エアロゾルの放射特性(体積消散係数、体積散乱係数、散乱の角度分布関数等)を、エアロゾルの化学組成分析結果に基づいて算出する手法を開発してきた。本研究では、この手法の妥当性を検証するために、エアロゾルのフィルター捕集時に直達日射・散乱日射の同時観測および積分型ネフェロメータによる体積散乱係数の同時測定を行った。すなわち、これらの光学的実測値と、フィルター捕集されたエアロゾルの化学組成分析結果に基づいて算出された値との比較・検討を行なった。対流圏エアロゾルを、黒色純炭素、有機物、硫酸アンモニウム、硝酸アンモニウム、海塩粒子および土壌粒子の6種類の単一成分粒子群と、黒色純炭素を核としてその上を硫酸アンモニウムの殻が覆っている混合核の7種類の粒子群から成るものと仮定した。なお、この混合核が全くない場合と、大気中に浮遊する黒色純炭素の半分と硫酸アンモニウム粒子の半分とが混合核を形成している場合、および大気中に浮遊する全黒色純炭素と全硫酸アンモニウムおよび黒色純炭素と同体積の有機物粒子により混合核が形成されている場合、の3種類の混合状態を考えた。また各成分粒子の粒径分布として3種類の粒径分布を仮定した。散乱日射量と直達日射量との比(直散比)について、実測値と、化学組成分析に基づいて算出されたものとの比較検討を行なったところ、実測値を良く再現する場合として、混合状態と粒径分布についての様々な組み合わせが得られてしまい、直散比から、混合状態および粒径分布の最適値を独立に推定することはできなかった。また、積分型ネフェロメータについては、吸引流量が小さ過ぎることがわかり、今後の改良が必要であることが分かった。
日本学術振興会, 特定領域研究(A), 北海道大学, 10144201

1つ1つの雲粒に含まれる化学種解明のためのサンプリング・分析手法の開発
科学研究費助成事業
1997 - 1998
山形 定
航空機用雲粒サンプラーおよび航空機搭載時に必要となるサンプラーカバーを作製した。このサンプラーは前年度に試作し、良好に動作した地上用雲粒サンプラーと同一原理で設計されている。今年度は雲を対象とした航空機観測が実施されなかったため、このサンプラーを実際航空機に搭載させ、雲粒のサンプリングをおこなうテストは実施できなかった。今後の観測に柔軟に対応するために、サンプラーカバーには汎用性を持たせ、プラッドホームとなる航空機が異なっても搭載できるような形とした。
雲粒痕跡内に存在する粒子中に硫酸イオンが存在するか否かを判定するためにサンプリング面への試薬薄膜の採用を検討した。いくつかの薄膜を実験室内で試験した結果、ポリビニルアルコールに塩化バリウムを含んだ薄膜をサンプリング面に用いると硫酸イオンを含む雲粒の痕跡のみ周辺にリング状の析出が見られた。これにより、昨年度X線分析では判別きなかったと考えられる硫酸イオンの検出が可能になった。また、雲粒径と痕跡径との関係を求め、雲粒内化学成分と同時に雲粒径も測定できるようにした。
昨年度同様、地上用サンプラーを用い釜石鉱山の立坑を利用した雲実験施設でテスト観測をおこなった。立坑底部で硫酸ミストを発生させた時に坑頂部で生成する雲粒をこの複合膜を用い観測した結果、硫酸イオンを含む雲粒と土壌粒子を含む雲粒ではそれぞれの粒径分布が異なることを明らかにした。
日本学術振興会, 奨励研究(A), 北海道大学, 09780474

Anthropogenic Emissions of Reduced Sulfur Compounds from Waste Water Facilities and Landfills in Sapporo
Grants-in-Aid for Scientific Research
1997 - 1998
MURAO Naoto, YAMAGATA Sadamu, OHTA Sachio
It has been suggested that reduced sulfur compounds such as carbonyl sulfide (COS) and carbon disulfide (CS2) play a significant role in the global and/or local climate through formation of sulfuric acid particles and clouds. In particular, because of its relatively long lifetime in the troposphere, transport of COS from the troposphere is believed to be the major source for the stratospheric aerosol layer which affect the Earth's radiation balance and climate. Until now numerous sources of COS have been identified and quantified, but the contribution of anthropogenic sources to the local and global COS burden is highly uncertain. The purpose of this study is to estimate contribution of anthropogenic emissions such as waste water facilities and landfills to ambient concentration in Sapporo.
With this aim, we first developed measurement method for monitoring ambient reduced sulfur gases using thermal desorpt ion - gas chromatography equipped with FPD.The method includes cryogenic preconcentration on TENAX.Breakthrough is not observed for samples up to 3 liter and recovery is found to be approximately 100%.
Measurements of ambient concentrations and emissions from various sources have been performed in Sapporo, Variation of ambient COS concentrations suggests a local source in Sapporo. However emission rates from vehicles and waste water facilities are found to be small enough to vary ambient concentration. Although quantification can not be made due to various interference, landfill gas contains large amount of reduced sulfur gases. In order to verify these findings characterization of sulfur containing landfill gases and extensive emission measurements are necessary.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), HOKKAIDO UNIVERSITY, 09650597

実験室スケールでの雲の生成とそのキャラクタリゼーション
科学研究費助成事業
1996 - 1996
山形 定
内径360mm,高さ1000mmのアクリルパイプを内管とする二重管構造をもつ室内雲チャンバーを作成した。チャンバー内は循環冷却水によって5〜15°Cに冷却され、内部に湿潤空気とエアロゾルが供給される。チャンバー内温度を5°Cにした時、90°Cの水蒸気飽和空気とエアロゾルを含む実験室内空気を導入するとチャンバー内に微水滴が生成することをレーザー光の散乱で確認した。
大気中の存在する土壌粒子が雲粒内に取り込まれるかどうかを検討するために、関東ローム試験用ダストの微粒子を流動床粒子発生装置で発生させ、雲チャンバー内に湿潤空気とともに導入した。関東ローム試験用ダストの場合は、ダストをチャンバー内に数十分滞留させた後に湿潤空気を導入すると微水滴が形成されることがわかった。雲粒サンプリング用に作成したインパクターを用い、この微水滴をウォーターブルー色素を塗布したフィルム上に捕集し顕微鏡観察したところ、微水滴内に土壌粒子が存在していることが確認された。
この事実は、試験管内で土壌粒子が亜硫酸イオンの光酸化速度を促進するという知見とあわせて考えると、極めて重要な意味を持つ。すなわち、大気中の雲粒は亜硫酸イオンの酸化など、さまざまな反応の場となっていることがフィールド観測や計算機シミュレーションなどから指摘されているが、本研究結果はそのプロセスに土壌粒子が関わっていることを示唆している。このことは、土壌粒子が雲粒内で種々の反応を引き起こし、大気中の化学組成に影響を与えるばかりでなく、水溶液反応で土壌粒子からさまざまな鉱物成分が溶出し、その成分が海洋の生態系へ影響を与える可能性も含んでいる。今後、大気中の雲粒内の土壌粒子分布を明らかにする必要がある。
日本学術振興会, 奨励研究(A), 北海道大学, 08780491

Evaluation of effect of suppresion due to increase of anthropogenic aerosols on the global warming
Grants-in-Aid for Scientific Research
1994 - 1996
OHTA Sachio, YAMAGATA Sadamu, HAGA Tetsuya, MURAO Naoto
An increase of atmospheric concentrations of anthropogenic aerosols with human activities suppresses the global warming. The suppresion, however, depends strongly on absorptivity of the aerosols in solar wavelengths region. It is, thus, important to determine the global distribution of the absorptivity of atmospheric aerosols. In the study, we measured monthly mean atmospheric concentration of total mass and chemical components of the aerosols from May 1995 through October 1996 at Cape Hedo, northern edge of Okinawa island, Japan, and chemically characterized the aerosols by using the measurement results.
We found that Okinawa aerosol consisted of elemental carbon, organics, sulfate, nitrate, ammonium, chloride, sea-salt cations and soil particles. Total mass concentration of the Okinawa aerosol was 3-11 mug/m^3 less than 2mum in diameter. In spring a large amount of anthropogenic sulfate, organic and elemental carbon particles were transported in addition to Yellow sands from Continental China. In summer, on the other hand, the atmospheric concentration of the total particulate mass was low, but the ratio of vanadium, nickel and cupper contents to the total mass were high, which indicated that the anthropogenic aerosols were distributed over the western Pacific Ocean.
Based on the chemical characterization, we calculated a single scattering albedo of the Okinawa aerosol. It was 0.95 in summer, 0.90 in winter and 0.92 in annual average. It means that the western Pacific maritime aerosol around Okinawa has little absorptivity and capability of suppressing the global warming due to the increase.
Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), HOKKAIDO UNIVERSITY, 06452280

雲内における土壌粒子エアロゾルの雲粒内・雲粒間分布
科学研究費助成事業
1995 - 1995
山形 定
従来より用いられているエアロゾル-ガスサンプリング装置に接続可能な雲粒サンプリング用のインパクターを作成した。これを用いることで、雲・霧内で液相成分の雲・霧粒、雲粒間に存在する微粒子、およびガスを同時に分析することが可能となった。
インパクターは2段になっており、それぞれの50%粒子カット径は、計算上10μm、2μmとした。ただし、単一粒径の粒子発生装置がないため、正確な50%カット径は求めていない。
この装置を用い、岩手県の釜石鉱山の廃坑となった立坑内に発生している雲をサンプリングした。立坑では海抜250m地点から空気が断熱的に膨張しながら海抜680m地点まで上昇する。サンプルは、雲生成前の気塊、雲生成直後の気塊、雲生成から10分程度経過後の気塊とした。また、立坑内に流入してくるエアロゾルをモニターするため、雲粒-エアロゾル-ガスサンプラーとは別に、全粒子状物質をサンプリングし、その重量を測定した。
釜石鉱山立坑内のエアロゾル重量は数μg/m^3と、札幌市内などの都市部に比べると1/10程度以下であることがわかった。このことは、立坑を巨大な雲チャンバーとみなし、種々の実験を行なうことが可能であることを示している。このようにエアロゾル濃度が低いこと、雲を含む気塊に対して2時間程度のサンプリングしか行なわなかったことから、現在の分析環境では土壌粒子の直接検出は不可能と考えられた。そこで、実際の大気中で土壌粒子と同一粒子を形成していることもある硫酸などの水溶性成分の分析を、検出限界の低いイオンクロマトグラフィーで行なった。その結果5回サンプリングしたうちの4回では、硫酸エアロゾル量は雲発生と同時にその90%程度が雲水中に取り込まれていることがわかった。
日本学術振興会, 奨励研究(A), 北海道大学, 07780451

PANの濃度変動からみた東アジア地域からの窒素酸化物の流出
科学研究費助成事業
1995 - 1995
村尾 直人, 山形 定, 大田 幸雄
PAN(Peroxyacetyl Nitrate)は、対流圏や大陸規模など広域の光化学過程や大気汚染物質の長距離輸送の評価に最適な物質である。本研究では、PANとともに大気中の長距離輸送に関連する各種汚染物質の測定を行い、1990年度冬期〜春期に観測されたPANの高濃度現象との関連を明らかにすることを第一の目的とした。まず、PANの濃度変動と関連する汚染物質として特に重要な炭化水素について、試料補集法および分析法を検討した。すなわち、試料の補集・分析法として常温吸着・熱脱離法を検討し、標準ガスを用いた再現性試験、保存性試験等の試験を行った。その結果、補集管は0℃に冷却することによって十分な補集効率および回収率が得られ、三日程度の保存が可能であることが分かった。このことから、常温吸着・熱脱離法はフィールド測定に適用可能であると考えられる。以上の結果をもとに、2月下旬より札幌郊外の手稲山山頂(高度1,000m)で観測を開始している。観測項目は、PAN、炭化水素、エアロゾル、オゾン、SO_2である。
次に、PANの濃度変動の要因、輸送過程を明らかにすることを目的とした輸送・反応モデル解析および流跡線解析を行った。まず、輸送・反応モデル解析を用いて、人為起源汚染物質の排出がPANの濃度変動に与える影響を検討したところ、NO_xとともに炭化水素、特にアルカン類排出の影響が大きいことが示された。したがって、東アジア地域の光化学環境を理解し予測するためには、今後NO_xとともに炭化水素排出量の正確な把握が不可欠であると思われる。一方、1990年度冬期〜春期に観測されたPANの高濃度現象に関する流跡線解析では、高濃度気塊が多くの場合、中国北部から一定高度で輸送されていることが示された。
日本学術振興会, 一般研究(C), 北海道大学, 07680548

Assessment of Urban Air Pollution in Siberian Wetland
Grants-in-Aid for Scientific Research
1994 - 1995
OHTA Sachio, LEVCHENKO G., MAKAROV V., YAMAGATA Sadamu, MURAO Naoto, KOUCHTCHEV M.
We have measured atmospheric concentrations of aerosol chemical species less than 2mum in diameter (atmospheric fine particles) and gaseous SO_2, HNO_3 and HC1 from August 1993 at Yakutsk, Tiksi and Norilsk in Siberia. We also measured atmospheric concentration of SO_2 and NO_2 in summer at Habarovsk, Yakutsk and Norilsk.
At Yakutsk most of the fine particles consisted of elemental carbon and organics whose concentrations were the same as those in Sapporo. At Tiksi the atmospheric fine particle concentration was one-tenth of those at Yakutsk. Most of the fine particles consisted of organics and sulfate. At Norilsk elemental carbon, organics and sulfate accounted for most of the fine particles whose concentration was the same as in Sapporo. The sulfate particle concentration, in particular, increased in spring and summer.
Atmospheric summer concentrations of SO_2 and NO_2 were low at Habarovsk and Yakutsk. But, in Norilsk, though NO_2 concentration was low, the concentration of SO_2 was extremely high in summer.
We evaluate the effects of atmospheric pollutants on the Arctic environment.
Japan Society for the Promotion of Science, Grant-in-Aid for international Scientific Research, Hokkaido University, 06041002

ネットワーク構造をもつ光触媒による小分子有機物の活性化
科学研究費助成事業
1993 - 1993
山形 定
1.ネットワーク構造をもつ光触媒としてTiを骨格に含むゼオライトであるTS-1を、従来よりも結晶性良く短期間で合成することに成功し、従来法で合成したものと同様に光触媒活性を持っていることを確認した。
2.ネットワーク構造を持つ光触媒を用いて小分子を活性化し、さらに選択的に生成物を得るためにはこれらの小分子をネットワーク内の活性点で反応させることが必要である。本研究ではゼオライト外表面の活性点を同じ構造を持ちTiを含まないザオライトであるシリカライトで被覆することにより小分子のふるい分けを試みた。被覆により細孔内に侵入できると考えられるエチレングリコールも反応しなくなった。このことはシリカライト被覆が小分子の細孔内活性点へのアクセスをも不可能にしたことを示しており、次のような解釈が可能である。
(1)反応を水溶液内で行なっていることから、分子がゼオライトの細孔径より小さくても水和などのため細孔内にはいれない。
(2)被覆がゼオライト表面の活性点だけにとどまらず、ゼオライト細孔部分にも起こり、小分子も細孔内にアクセスできなくなった。
3.今回得られた結果より、TS-1の光触媒反応選択性を見るためには反応基質が単分子状態で存在する気相で反応を行わせることが必要である考えられる。気相で分子サイズの異なる物質の反応性をみることでシリカライト被覆が適正に行われているか否かの判断が可能となるであろう。
4.気相では熱を活性化エネルギーとして用いる通常の触媒反応がゼオライトに関しても数多く研究されている。これまでにそこで蓄積された研究結果と光触媒での結果を比較検討することにより、TS-1などのネットワーク構造をもつ光触媒に関する知見が深まると期待できる。
日本学術振興会, 奨励研究(A), 北海道大学, 05855121

PANの測定による対流圏光化学反応過程の評価
科学研究費助成事業
1993 - 1993
村尾 直人, 山形 定, 太田 幸雄
本研究では、対流圏や大陸規模など広域の光化学過程や大気汚染物質の長距離輸送に関する評価物質であると考えられるPAN(Peroxyacetyl Nitrate)について、その連続測定が可能となるような測定方法の自動化を行うとともに、モデル計算によって濃度変動の要因およびその時間・空間規模を明らかにすることを目的とした。
測定方法の自動化では、標準ガスを用いた再現性試験等、測定装置に関する各種の試験を終えた。測定装置は10ポートバルブ(温度コントロール付き)付ガスクロマトグラフ、インテグレータ、ポンプ等の外部装置を制御するコントローラからなり、一定時間おきに試料の導入、分析、定量を自動的に行うことができる。
一方、モデル計算では、経度-高度の2次元大気輸送・化学モデルの構築を行い、地域規模あるいは大陸規模といった空間スケールで起こるPANの濃度変動について検討を行った。計算結果をこれまでの観測結果と比較すると、冬期〜春期にかけての高く、夏期〜秋期にかけて低い濃度となる季節変動は再現できたが、定量的には高濃度がより高く、低濃度がより低い結果となった。また、北半球中緯度帯のPANの高度-経度分布は、気温および一次汚染物質の発生源の位置により形態が決定され、季節変動は汚染物質の大気中濃度と日射量、気温のバランスにより決定されていると考えられる。具体的には、冬季にはヨーロッパ、アジア、アメリカで濃度が高く、大陸西岸からその大陸の東方海上にかけて大陸規模の濃度変動が見られるが、夏季はヨーロッパや北アメリカ大陸東部など汚染物質の発生源の近傍に濃度が高い領域が限られた。また、対流圏におけるPAN濃度の変動は対流圏内の各種化学種濃度に影響を及ぼしていることが示された。
日本学術振興会, 一般研究(C), 北海道大学, 05680439

東アジア地域における硫黄酸化物の収支
科学研究費助成事業
1992 - 1992
村尾 直人, 山形 定, 太田 幸雄
本研究では、これまでに開発した東アジア地域を対象とした酸性雨モデルを用いて、日本域における硫黄酸化物の収支を求めるとともに、日本各地で観測される硫黄酸化物の沈着量に対する各種発生源(国外発生源、国内発生源、火山(桜島))の寄与を明らかにすることを目的とした。
各種発生源の寄与では、(1)すべての発生源を含む計算、(2)火山からの排出を取り除いた計算、(3)国外発生源および火山からの排出を取り除いた計算、を行い、それぞれの計算結果の差から、各種発生源の寄与を日本各地について求めた。冬期に関する結果では、(1)太平洋側の諸都市での沈着量は小さいが国内発生源の寄与が最も大きいこと、(2)火山からのSO_2排出の影響はいづれの地点においても小さいこと、(3)国外発生源の寄与は特に日本海側で大きく70%以上の値にもなること等が得られた。また、将来の経済発展に伴う排出量増加の影響を予測する目的で、国外発生源からの排出量を2割増した場合の日本各地の沈着量の増加割合を求めた。その結果でも日本海側の地点での沈着量増加が大きく、この地域では海外発生源の増加にほぼ等しい沈着量の増加があることがわかった。逆に太平洋側での増加は5%以下で、その影響は小さい。
日本域での硫黄酸化物の収支推定からは以下の3点が明らかとなった。すなわち、第一に、大陸からの汚染物質の流入は年間を通じてあり、降水量の分布・季節変動によって特にその影響が冬期の日本海側に強く見られると考えられること、第二に、本邦地域での沈着と排出によって、いずれの月においても流入量とほぼ同量が太平洋に流出していること、第三に、大陸からの流入は高低気圧の通過が多い春期に最も大きい値となっていることである。
日本学術振興会, 重点領域研究, 北海道大学, 04202202

人為起源大気エアロゾルの増加が地球温暖化に及ぼす影響の評価
科学研究費助成事業
1991 - 1991
太田 幸雄, 山形 定, 村尾 直人
本研究では、まず地球大気中のエアロゾルを、北極圏大気エアロゾル、陸上(大陸性)大気エアロゾル、北半球海洋大気エアロゾル、南半球海洋大気エアロゾルおよび南極大気エアロゾルの5つのタイプに区分した。次にこれまでに世果各地で様々な研究者により行われてきたエアロゾルの成分測定結果について文献調査を行い、さらに本研究班が小笠原諸島や北海道ニセコ山麓で行ってきた成分測定結果をも合わせて、上記の5つのエアロゾルについて組成分析結果に基づきその光学特性を与えた。また、これまで行われた光学的厚さの測定結果を基に地球規模での大気エアロゾルの分布を得た。以上のエアロゾル分布に対して、放射伝達方程式を解いて大気上端での太陽放射反射率を求め、ブディコ型の熱収支気候モデルを適用することにより、まず、現在存在している大気エアロゾルが地球の気候に及ぼしている効果を見積もったところ、現存するエアロゾルにより地球は約1℃冷却されていることが分かった。次に、今後の人間活動の拡大の結果として、大気エアロゾルのうち特に煤粒子と硫酸粒子が2倍に増加した場合の影響を予測した。煤粒子のみが全球的に2倍に増加した場合には極域で0.8℃と、熱帯域で0.2℃の気温上昇をもたらすが、一方硫酸粒子のみが2倍に増加した場合には逆に極域で0.3℃、熱帯域で0.1℃の気温低下をもたらし、人為起源大気エアロゾルの増加は地球温暖化に対して無視し得ない影響を及ぼすことが分かった。ただし、以上の計算に用いられた大気エアロゾルの全球分布モデルは散発的な光学的厚さのデ-タに基づいて作成されたものである。それゆえ、現在、人工衛星デ-タを用いた大気エアロゾルの全球分布の推定法についての研究を継続中である。人工衛星NOAAデ-タを用いた北海道沖の海上大気エアロゾル量の推定では実測値とよく合う結果が得られており、今後、この研究を継続して行く予定である。
日本学術振興会, 一般研究(C), 北海道大学, 03805046

東アジア地域を対象とした酸性雨モデルの開発
科学研究費助成事業
1991 - 1991
村尾 直人, 山形 定, 太田 幸雄
本研究では、まず日本の人為発生源と同程度のSO_2俳出量を持つ火山(桜島)の取り扱いの検討と評価を、次に日本各地における各種発生源からの寄与の見積もりおよび日本域での硫黄酸化物の収支に関する試算を行った。本研究で得られた主要な結果を以下にまとめる。
(1) 桜島の影響:1988年2月、4月に関する流跡線解析結果では、桜島の影響が冬期には小さく、春期のように頻繁に高低気圧が通過する時期に大きいことが示唆された。それぞれの月について、酸性雨モデル計算により、日本各地の硫黄酸化物の沈着量に対する桜島の寄与を求めた。その結果、桜島に由来する沈着量は、2月ではいずれの地点も12(mg/m^2/月)以下と小さい値となったが、4月では、15ー137(mg/m^2/月)となり全沈着量に対する寄与率では、名古屋、大阪、広島、高知で20%を上まわる結果となった。これらの結果に関しては、今後観測結果による十分な検証が必要と思われるが、日本地における酸性物質の沈着に関して桜島の影響が大きいことを示すものとして注目できる。
(2) 日本域での硫黄酸化物の収支推定;1988年2月に関する日本域での硫黄酸化物の月間物質収支を試算した。その結果によれば、硫黄酸化物はSO_2換算で20万トンがアジア大陸側から流入し、22万トンが太平洋側に流出する。日本域では、10万トンが人為発生源により、また、9万トンが火山から排出され、11万トンがこの領域で沈着する。見かけ上、アジア大陸の発生源による寄与はないが、この時期火山からの9万トンはほとんどがそのまま太平洋側への流出量となること等からみて、相当量が本邦地域で入れ代わっていると考えられる。
今後さらに、他の季節に関する解析を進めるとともに、日本各地の酸性物質沈着量に対する大陸起源の汚染物質の寄与を求めることが必要と考えられる。
日本学術振興会, 重点領域研究, 北海道大学, 03202201

東アジア地域における汚染物質の長距離輸送過程の解析
科学研究費助成事業
1990 - 1990
村尾 直人, 山形 定, 太田 幸雄
本研究では、中国東部、台湾、韓国、北朝鮮を含む地域を対象として酸性雨現象のモデル化を行い、今後の環境保全対策に資することを目的とした。本研究で得られた結果を以下にまとめる。
(1)SO_2沈着量は、乾性及び湿性沈着がほぼ同等に寄与している。一方、SO_4^<2ー>沈着量は湿性沈着の寄与が大きく、その分布は降水量分布を反映したものとなっている。(2)SO_2、SO_4^<2ー>の地上濃度(国内)は、実測値とほぼ一致している。国外の観測デ-タが乏しいため、妥当性の評価はできないが、韓国(ソウル)、中国(重慶)等ではSO_2発生量が極めて高く、地上濃度も10pp以上となっている。(3)冬期の日本海測で、近隣諸国の発生源からの影響が強く見られたが、全体に計算値は実測値よりもかなり小さい値となった。これは、実測値のない日本海域での降水量を陸上の値を参考に与えているため、海域での沈着量を過剰評価しているためと思われる。また、夏期には、我が国への近隣諸国の発生源の寄与は小さいことが示唆された。(4)乾性沈着速度及び洗浄比の酸性降下物量に与える影響は大きく、特に洗浄比は局所的な沈着量に大きな感度を持つ。(5)本研究のような長期モデルでは国内の火山により影響の評価は難しいが、一部の測定点では、その影響が示唆された。
以上のように、実測から示唆されている近隣諸国の発生源からの影響が、本研究において確認され、また、感度解析によりモデルの挙動についても明らかにすることができた。しかし、計算値の妥当性の評価や日本海域でのデ-タの扱い等、検討が必要と考えられる点も少なくない。今後、使用デ-タの変更を含めて、モデルの改良を行う必要があろう。
日本学術振興会, 重点領域研究, 北海道大学, 02202201