DSpace Collection: 2010-03-31
http://hdl.handle.net/2115/45154
2010-03-312024-03-28T20:33:34Zモデリング研究によるエアロゾル気候影響評価
http://hdl.handle.net/2115/45173
Title: モデリング研究によるエアロゾル気候影響評価
Authors: 竹村, 俊彦
Abstract: 大気エアロゾルは, 直接・準直接・間接効果, およびそれらの結果として起こる効果により気候変動に影響を及ぼす. エアロゾルの気候影響を評価するために, 全球エアロゾル気候モデルSPRINTARSを開発してきた. 本稿では, SPRINTARSを用いた研究を中心として, 数値モデルによるエアロゾルの気候影響評価に関連する近年の研究の動向を紹介する.; Atmospheric aerosols affect climate change through the direct, semi-direct, indirect, and their secondary effects. The author has developed a global aerosol climate model, SPRINTARS, to estimate the aerosol climate effects. In this manuscript recent trends related to studies on estimates of aerosol climate effects with numerical models, mainly SPRINTARS, are introduced.2010-03-30T15:00:00Z竹村, 俊彦大気エアロゾルは, 直接・準直接・間接効果, およびそれらの結果として起こる効果により気候変動に影響を及ぼす. エアロゾルの気候影響を評価するために, 全球エアロゾル気候モデルSPRINTARSを開発してきた. 本稿では, SPRINTARSを用いた研究を中心として, 数値モデルによるエアロゾルの気候影響評価に関連する近年の研究の動向を紹介する.
Atmospheric aerosols affect climate change through the direct, semi-direct, indirect, and their secondary effects. The author has developed a global aerosol climate model, SPRINTARS, to estimate the aerosol climate effects. In this manuscript recent trends related to studies on estimates of aerosol climate effects with numerical models, mainly SPRINTARS, are introduced.植生改変・エアロゾル複合効果がアジアの気候に及ぼす影響の評価
http://hdl.handle.net/2115/45172
Title: 植生改変・エアロゾル複合効果がアジアの気候に及ぼす影響の評価
Authors: 須藤, 健悟; 高田, 久美子; 竹村, 俊彦; 神沢, 博; 安成, 哲三
Abstract: アジア域では, 土地利用変化などに伴う植生改変およびエアロゾルの増加が顕著であり, これらの変動は陸面過程, 大気放射, および雲・降水を変化させ, アジアモンスーンなどのアジア域気候に影響している可能性が大きい. 本研究では, 植生改変とエアロゾル変動の役割という観点から, 総合的に気候影響を検討している. 本論文では, 特に, 農地化などの土地利用変化が, 陸面, および硝酸塩や植生起源有機炭素などのエアロゾル成分の変動を通じて, どのように気候に影響するかについて, 全球化学・エアロゾル気候モデルを用いた最新の結果について紹介する.; This study assesses the roles of aerosols in the past/present changes in Asian climate and monsoon, isolating impacts of individual aerosol components in the framework of the CCSR/NIES/FRCGC climate model (MIROC). Many recent studies suggest that increases in anthropogenic aerosols such as black carbon and sulfate may play a crucial role in Asian climate change as observed. Our previous studies also demonstrate the significance of aerosol increases (sulfate and carbonaceous aerosols) in the simulated precipitation changes in Asia (e.g.,Arai et al., 2009). In this study, we particularly focus on the changes of nitrate and secondary organic aerosols (SOA) which are tightly linked to land use change in regions like Asia, but not treated in our previous aerosol studies. We newly introduced simulation of nitrate aerosol in our climate model. Our simulation shows that there are anomalously high concentrations of nitrate aerosol in South Asia (particularly around India and Bangladesh), coming from abundant ammonium and less sulfate components in this region. In India, free tropospheric mixing ratio and number concentration of nitrate in fine mode are both larger than those of sulfate in winter to early summer. Our study estimates large cooling (1-2 W m-2)in South Asia due to nitrate increase in terms of direct radiative forcing for 1850-2000. This result suggests nitrate aerosol may play an important role in the observed changes in Asian monsoon. In addition, we estimate changes in biogenic VOCs emissions associated with land use change during 1850-2000; biogenic VOCs like terpenes are important precursors of SOA. We estimate significant reduction (50-70%) in terpenes and other VOCs emissions in the central Eurasia, North America, and Asia due to intense cultivation and deforestation in these areas. Responding to the VOCs decreases during 1850-2000, our model calculates large reduction of SOA, leading to a positive direct radiative forcing (warming) of 0.5-1 W m-2 in South Asia. This warming from SOA and cooling from nitrate aerosol which are both linked to land use change may compensate for each other in Asia.2010-03-30T15:00:00Z須藤, 健悟高田, 久美子竹村, 俊彦神沢, 博安成, 哲三アジア域では, 土地利用変化などに伴う植生改変およびエアロゾルの増加が顕著であり, これらの変動は陸面過程, 大気放射, および雲・降水を変化させ, アジアモンスーンなどのアジア域気候に影響している可能性が大きい. 本研究では, 植生改変とエアロゾル変動の役割という観点から, 総合的に気候影響を検討している. 本論文では, 特に, 農地化などの土地利用変化が, 陸面, および硝酸塩や植生起源有機炭素などのエアロゾル成分の変動を通じて, どのように気候に影響するかについて, 全球化学・エアロゾル気候モデルを用いた最新の結果について紹介する.
This study assesses the roles of aerosols in the past/present changes in Asian climate and monsoon, isolating impacts of individual aerosol components in the framework of the CCSR/NIES/FRCGC climate model (MIROC). Many recent studies suggest that increases in anthropogenic aerosols such as black carbon and sulfate may play a crucial role in Asian climate change as observed. Our previous studies also demonstrate the significance of aerosol increases (sulfate and carbonaceous aerosols) in the simulated precipitation changes in Asia (e.g.,Arai et al., 2009). In this study, we particularly focus on the changes of nitrate and secondary organic aerosols (SOA) which are tightly linked to land use change in regions like Asia, but not treated in our previous aerosol studies. We newly introduced simulation of nitrate aerosol in our climate model. Our simulation shows that there are anomalously high concentrations of nitrate aerosol in South Asia (particularly around India and Bangladesh), coming from abundant ammonium and less sulfate components in this region. In India, free tropospheric mixing ratio and number concentration of nitrate in fine mode are both larger than those of sulfate in winter to early summer. Our study estimates large cooling (1-2 W m-2)in South Asia due to nitrate increase in terms of direct radiative forcing for 1850-2000. This result suggests nitrate aerosol may play an important role in the observed changes in Asian monsoon. In addition, we estimate changes in biogenic VOCs emissions associated with land use change during 1850-2000; biogenic VOCs like terpenes are important precursors of SOA. We estimate significant reduction (50-70%) in terpenes and other VOCs emissions in the central Eurasia, North America, and Asia due to intense cultivation and deforestation in these areas. Responding to the VOCs decreases during 1850-2000, our model calculates large reduction of SOA, leading to a positive direct radiative forcing (warming) of 0.5-1 W m-2 in South Asia. This warming from SOA and cooling from nitrate aerosol which are both linked to land use change may compensate for each other in Asia.有機化合物の分子レベル安定炭素・水素同位体比測定法の大気化学への応用
http://hdl.handle.net/2115/45171
Title: 有機化合物の分子レベル安定炭素・水素同位体比測定法の大気化学への応用
Authors: 山本, 真也; 河村, 公隆
Abstract: 大気エアロゾル中の陸上高等植物バイオマーカーは, 有機物トレーサーとして, 低-中緯度域における陸起源有機物の長距離輸送の実態解明に大きく貢献してきた. しかし, 北西太平洋域など中-高緯度域に長距離輸送される陸起源有機物の起源・輸送過程の詳細を明らかにするためには, 従来の起源域指標に代わる新たな指標が必要不可欠である. 近年, 筆者らによる有機エアロゾルの同位体地球化学的研究により, 各有機分子の安定水素同位体比にその起源・輸送に関する情報が記録されていることがわかってきた. 本稿では, 最近の分子レベル安定同位体比の測定例について解説し, 都市エアロゾルへの応用例を紹介する.; The Asian continent is the major source region of terrigenous organic matter transported to the northwestern Pacific. However, biomarker proxies, such as molecular composition and compound-specific carbon isotopic ratios of leaf wax n-alkanes, do not have enough resolution for the recognition of their source vegetation in mid-high latitudes. Hence, development of a novel biomarker proxy is required to reveal their detailed source area and transport pathways. Our recent studies show that the compound-specific hydrogen isotopic compositions (δD) of atmospheric n-alkanes could provide the key to better understanding the long-range transport in the East Asia-northwestern Pacific regions.2010-03-30T15:00:00Z山本, 真也河村, 公隆大気エアロゾル中の陸上高等植物バイオマーカーは, 有機物トレーサーとして, 低-中緯度域における陸起源有機物の長距離輸送の実態解明に大きく貢献してきた. しかし, 北西太平洋域など中-高緯度域に長距離輸送される陸起源有機物の起源・輸送過程の詳細を明らかにするためには, 従来の起源域指標に代わる新たな指標が必要不可欠である. 近年, 筆者らによる有機エアロゾルの同位体地球化学的研究により, 各有機分子の安定水素同位体比にその起源・輸送に関する情報が記録されていることがわかってきた. 本稿では, 最近の分子レベル安定同位体比の測定例について解説し, 都市エアロゾルへの応用例を紹介する.
The Asian continent is the major source region of terrigenous organic matter transported to the northwestern Pacific. However, biomarker proxies, such as molecular composition and compound-specific carbon isotopic ratios of leaf wax n-alkanes, do not have enough resolution for the recognition of their source vegetation in mid-high latitudes. Hence, development of a novel biomarker proxy is required to reveal their detailed source area and transport pathways. Our recent studies show that the compound-specific hydrogen isotopic compositions (δD) of atmospheric n-alkanes could provide the key to better understanding the long-range transport in the East Asia-northwestern Pacific regions.三酸素同位体組成を指標に用いた大気沈着窒素 : 森林生態系間相互作用の定量的評価法
http://hdl.handle.net/2115/45170
Title: 三酸素同位体組成を指標に用いた大気沈着窒素 : 森林生態系間相互作用の定量的評価法
Authors: 角皆, 潤; 小松, 大祐; 代田, 里子; Kazemi, Gholam Abbas; 中川, 書子; 野口, 泉; 張, 勁
Abstract: 近年東アジア域を中心に大気中への人為的固定態窒素(NOxなど)の放出量が増大しつつあり, これがもたらすNO^[-]_[3]沈着量の増大が, 森林などの陸上生態系に与える影響について関心が集まっている. 森林生態系は, 大気から沈着するNO^[-]_[3](NO_[3]^[-]_[atm])の多くを光合成(同化)過程において吸収していると一般に考えられているが, 森林生態系は多要素からなる複雑系で不均質性が高い. さらに, 有機体窒素から再生したNO^[-]_[3](NO_[3]^[-]_[re])に関しては放出源として挙動するため, ある森林生態系の局所的観測から, 全体の吸収量を定量化したり, 森林生態系毎の吸収量の差異を評価したりすることは難しい. そこで近年, NO_[3]^[-]_[atm]だけが自然発生源で唯一0以外の値を示し, かつ一般の反応過程おいて値が変化しない, NO^[-]_[3]の三酸素同位体組成(Δ17O値)を利用する方法が提案されている[Michalski et al., 2004b; Tsunogai et al., 2010]. これは森林生態系を経由して流出した地下水中に含まれるNO^[-]_[3]のΔ17O組成が, 大気から沈着したNO^[-]_[3]と森林生態系内で生成したNO^[-]_[3]の混合比を反映していることを利用している. この新手法を用いることで, 森林生態系環境に変化・擾乱を与えず, また手間やコストを大幅に削減しながら, より信頼度の高い見積値の算出を実現出来る可能性がある. 本論文では東アジア域で初めてNO^[-]_[3]のΔ17O組成を指標に用いて, 大気から沈着した窒素と森林生態系の相互作用を評価した研究[Tsunogai et al.,2010]についてレビューし, その有用性を検証する.; This paper reviews recent advances in using the 17O anomalies (Δ17O) to trace the fate of atmospheric nitrate that had deposited onto a forest ecosystem, especially for the recent studies by Tsunogai et al.[2010]in which the fate of atmospheric nitrate deposited onto a forest ecosystem have been successfully traced by Δ17O for the first time in East Asia. In the study, the stable isotopic compositions of nitrate in precipitation (wet deposition) and groundwater (spring, lake, and stream water) were determined for the island of Rishiri, Japan, which is a representative background forest ecosystem for East Asia. The deposited nitrate had large 17O anomalies with Δ17O values ranging from +20.8 ‰ to +34.5 ‰ (n=32) with +26.2 ‰ being the annual average. On the other hand, nitrate in groundwater had small Δ17O values ranging from +0.9 ‰ to 3.2 ‰ (n=19), which corresponds to an mixing ratio of atmospheric nitrate to total nitrate of 7.4±2.6 %. Comparing the inflow and outflow of atmospheric nitrate in groundwater within the island, Tsunogai et al.[2010]estimated that the direct drainage accounts for 8.8±4.6% of atmospheric nitrate that has deposited on the island and that the residual portion has undergone biological processing before being exported from the forest ecosystem.2010-03-30T15:00:00Z角皆, 潤小松, 大祐代田, 里子Kazemi, Gholam Abbas中川, 書子野口, 泉張, 勁近年東アジア域を中心に大気中への人為的固定態窒素(NOxなど)の放出量が増大しつつあり, これがもたらすNO^[-]_[3]沈着量の増大が, 森林などの陸上生態系に与える影響について関心が集まっている. 森林生態系は, 大気から沈着するNO^[-]_[3](NO_[3]^[-]_[atm])の多くを光合成(同化)過程において吸収していると一般に考えられているが, 森林生態系は多要素からなる複雑系で不均質性が高い. さらに, 有機体窒素から再生したNO^[-]_[3](NO_[3]^[-]_[re])に関しては放出源として挙動するため, ある森林生態系の局所的観測から, 全体の吸収量を定量化したり, 森林生態系毎の吸収量の差異を評価したりすることは難しい. そこで近年, NO_[3]^[-]_[atm]だけが自然発生源で唯一0以外の値を示し, かつ一般の反応過程おいて値が変化しない, NO^[-]_[3]の三酸素同位体組成(Δ17O値)を利用する方法が提案されている[Michalski et al., 2004b; Tsunogai et al., 2010]. これは森林生態系を経由して流出した地下水中に含まれるNO^[-]_[3]のΔ17O組成が, 大気から沈着したNO^[-]_[3]と森林生態系内で生成したNO^[-]_[3]の混合比を反映していることを利用している. この新手法を用いることで, 森林生態系環境に変化・擾乱を与えず, また手間やコストを大幅に削減しながら, より信頼度の高い見積値の算出を実現出来る可能性がある. 本論文では東アジア域で初めてNO^[-]_[3]のΔ17O組成を指標に用いて, 大気から沈着した窒素と森林生態系の相互作用を評価した研究[Tsunogai et al.,2010]についてレビューし, その有用性を検証する.
This paper reviews recent advances in using the 17O anomalies (Δ17O) to trace the fate of atmospheric nitrate that had deposited onto a forest ecosystem, especially for the recent studies by Tsunogai et al.[2010]in which the fate of atmospheric nitrate deposited onto a forest ecosystem have been successfully traced by Δ17O for the first time in East Asia. In the study, the stable isotopic compositions of nitrate in precipitation (wet deposition) and groundwater (spring, lake, and stream water) were determined for the island of Rishiri, Japan, which is a representative background forest ecosystem for East Asia. The deposited nitrate had large 17O anomalies with Δ17O values ranging from +20.8 ‰ to +34.5 ‰ (n=32) with +26.2 ‰ being the annual average. On the other hand, nitrate in groundwater had small Δ17O values ranging from +0.9 ‰ to 3.2 ‰ (n=19), which corresponds to an mixing ratio of atmospheric nitrate to total nitrate of 7.4±2.6 %. Comparing the inflow and outflow of atmospheric nitrate in groundwater within the island, Tsunogai et al.[2010]estimated that the direct drainage accounts for 8.8±4.6% of atmospheric nitrate that has deposited on the island and that the residual portion has undergone biological processing before being exported from the forest ecosystem.大気エアロゾル中の低分子ジカルボン酸の分布と安定炭素同位体比
http://hdl.handle.net/2115/45169
Title: 大気エアロゾル中の低分子ジカルボン酸の分布と安定炭素同位体比
Authors: 河村, 公隆
Abstract: 低分子ジカルボン酸の安定炭素同位体比(δ13C)の測定法について説明し, 海洋エアロゾル試料中のジカルボン酸のδ13C値の特徴とそれから得られる大気化学情報解読の可能性について解説する. 本研究では赤道域を含む外洋大気中でシュウ酸など低分子ジカルボン酸が生物起源有機物の安定炭素同位体比にくらべ極めて高いδ13C 値を示すことを見つけた. 本稿では, その結果について概説するとともに, 低分子ジカルボン酸の安定炭素同位体比を有機エアロゾルの光化学的変質(エイジング)のトレーサーとして使える可能性についても考察する.; Stable carbon isotopic composition (δ13C) has been studied for C2-C9 diacids in the remote marine aerosols (n=32) collected from the Pacific Ocean including tropics (34°N-14°S, 140°E-150°W). Their isotopic compositions showed a diverse variation with the highest values in oxalic (C2) acid (range: +4.1 to +15.3‰,av.+10.3‰), followed by malonic (C3) acid (-11.2 to -3.1‰, av.-7.3‰) and succinic (C4) acid (-29.9 to -11.2‰, av.-17.6‰). The isotope ratios generally decrease with an increase in their carbon chain length, showing the lowest value of azelaic (C9) acid (av. -22.4‰). Although a significant enrichment of 13C in oxalic acid was found in all the remote marine aerosol samples, highest δ13C values were observed in the samples collected in the equatorial Pacific. We found that the δ13C values sharply increased as a function of ambient temperature and relative abundance of diacid-carbon in TC at a latitudinal transect in the western (0-35°N) and central equatorial Pacific (18°S to 20°N). This study suggests that photochemically induced degradation may be responsible to the enrichment of 13C in the C2-C4 diacids in the remote marine atmosphere. We propose that δ13C values of small diacids can be used as potential tracer of photochemical aging of organic aerosols.2010-03-30T15:00:00Z河村, 公隆低分子ジカルボン酸の安定炭素同位体比(δ13C)の測定法について説明し, 海洋エアロゾル試料中のジカルボン酸のδ13C値の特徴とそれから得られる大気化学情報解読の可能性について解説する. 本研究では赤道域を含む外洋大気中でシュウ酸など低分子ジカルボン酸が生物起源有機物の安定炭素同位体比にくらべ極めて高いδ13C 値を示すことを見つけた. 本稿では, その結果について概説するとともに, 低分子ジカルボン酸の安定炭素同位体比を有機エアロゾルの光化学的変質(エイジング)のトレーサーとして使える可能性についても考察する.
Stable carbon isotopic composition (δ13C) has been studied for C2-C9 diacids in the remote marine aerosols (n=32) collected from the Pacific Ocean including tropics (34°N-14°S, 140°E-150°W). Their isotopic compositions showed a diverse variation with the highest values in oxalic (C2) acid (range: +4.1 to +15.3‰,av.+10.3‰), followed by malonic (C3) acid (-11.2 to -3.1‰, av.-7.3‰) and succinic (C4) acid (-29.9 to -11.2‰, av.-17.6‰). The isotope ratios generally decrease with an increase in their carbon chain length, showing the lowest value of azelaic (C9) acid (av. -22.4‰). Although a significant enrichment of 13C in oxalic acid was found in all the remote marine aerosol samples, highest δ13C values were observed in the samples collected in the equatorial Pacific. We found that the δ13C values sharply increased as a function of ambient temperature and relative abundance of diacid-carbon in TC at a latitudinal transect in the western (0-35°N) and central equatorial Pacific (18°S to 20°N). This study suggests that photochemically induced degradation may be responsible to the enrichment of 13C in the C2-C4 diacids in the remote marine atmosphere. We propose that δ13C values of small diacids can be used as potential tracer of photochemical aging of organic aerosols.Comparison of Amazonian biomass burning and East Asian marine aerosols : Bulk organics, diacids and related compounds, water-soluble inorganic ions, stable carbon and nitrogen isotope ratios
http://hdl.handle.net/2115/45168
Title: Comparison of Amazonian biomass burning and East Asian marine aerosols : Bulk organics, diacids and related compounds, water-soluble inorganic ions, stable carbon and nitrogen isotope ratios
Authors: Kundu, Shuvashish; Kawamura, Kimitaka; Lee, Meehye; Andreae, Tracey W.; Hoffer, András; Andreae, Meinrat O.
Abstract: In this study, biomass burning and marine aerosols collected in the Amazon, Brazil and on an island south of South Korea are compared in terms of chemical characteristics and ageing by the determination of water-soluble organic carbon (WSOC), water-insoluble organic carbon (WIOC), elemental carbon (EC), diacids (C2-C11) and related compounds (ketoacids and α-dicarbonyls), stable carbon isotopic ratios (δ13C) of total carbon (TC), and nitrogen isotopic ratios (δ15N) of total nitrogen (TN). The concentration ratios of WSOC, WIOC, and EC to aerosol mass are 2-12 times higher in biomass burning aerosols than in marine aerosols. In contrast, concentration ratios of water-soluble cations and anions to aerosol mass are lower by a factor of 0.2-0.6 in biomass burning aerosols than in marine aerosols. Among diacids and related compounds, oxalic acid (C2) was found to be the most abundant, followed by succinic acid (C4) in biomass burning aerosols, while malonic acid (C3) dominated in marine aerosols. Lower relative abundances of C2-C4 diacids, unsaturated diacids, and α-dicarbonyls in total diacids and related compounds were observed in biomass burning aerosols than in marine aerosols, whereas those of C5-C11 diacids, branched diacids, multifunctional diacids, and ketoacids were higher in biomass burning aerosols. These results suggest that there are significant differences in the sources and photochemical production pathways of individual diacids and related compounds. While the δ13C values (-26.5 to -20.5‰) of TC and δ15N values (+6.8 to +26.9 ‰) of TN showed a large variation in marine aerosols, the variations were rather small (δ13C:-26.1 to -23.6‰; δ15N: +21.5 to +25.7‰) in biomass-burning aerosols. We propose that these δ13C and δ15N values can be used to characterize biomass-burning aerosols.2010-03-30T15:00:00ZKundu, ShuvashishKawamura, KimitakaLee, MeehyeAndreae, Tracey W.Hoffer, AndrásAndreae, Meinrat O.In this study, biomass burning and marine aerosols collected in the Amazon, Brazil and on an island south of South Korea are compared in terms of chemical characteristics and ageing by the determination of water-soluble organic carbon (WSOC), water-insoluble organic carbon (WIOC), elemental carbon (EC), diacids (C2-C11) and related compounds (ketoacids and α-dicarbonyls), stable carbon isotopic ratios (δ13C) of total carbon (TC), and nitrogen isotopic ratios (δ15N) of total nitrogen (TN). The concentration ratios of WSOC, WIOC, and EC to aerosol mass are 2-12 times higher in biomass burning aerosols than in marine aerosols. In contrast, concentration ratios of water-soluble cations and anions to aerosol mass are lower by a factor of 0.2-0.6 in biomass burning aerosols than in marine aerosols. Among diacids and related compounds, oxalic acid (C2) was found to be the most abundant, followed by succinic acid (C4) in biomass burning aerosols, while malonic acid (C3) dominated in marine aerosols. Lower relative abundances of C2-C4 diacids, unsaturated diacids, and α-dicarbonyls in total diacids and related compounds were observed in biomass burning aerosols than in marine aerosols, whereas those of C5-C11 diacids, branched diacids, multifunctional diacids, and ketoacids were higher in biomass burning aerosols. These results suggest that there are significant differences in the sources and photochemical production pathways of individual diacids and related compounds. While the δ13C values (-26.5 to -20.5‰) of TC and δ15N values (+6.8 to +26.9 ‰) of TN showed a large variation in marine aerosols, the variations were rather small (δ13C:-26.1 to -23.6‰; δ15N: +21.5 to +25.7‰) in biomass-burning aerosols. We propose that these δ13C and δ15N values can be used to characterize biomass-burning aerosols.Contributions of isoprene, α/β-pinene and β-caryophyllene to secondary organic aerosol in tropical India
http://hdl.handle.net/2115/45167
Title: Contributions of isoprene, α/β-pinene and β-caryophyllene to secondary organic aerosol in tropical India
Authors: Fu, Pingqing; Kawamura, Kimitaka; Pavuluri, Chandra M.; Chen, Jing; Swaminathan, T.
Abstract: Polar organic tracers of isoprene, α/β-pinene and β-caryophyllene photooxidation in tropical Indian aerosols (PM10) collected at Chennai were measured using gas chromatography/mass spectrometry. All the biogenic secondary organic aerosol (SOA) tracers showed diurnal variations with higher concentrations at daytime, which is in agreement with the fact that they are photochemical oxidation products of biogenic volatile organic compounds (VOCs). Total concentration ranges of the organic tracers were 18.3-107 ng m^[-3] in summer versus 2.69-66.9 ng m^[-3] in winter. Most of the SOA tracers showed higher concentrations in summer than in winter, while β-caryophyllinic acid, a tracer for β-caryophyllene, showed no seasonal differences. A good correlation (R2=0.67) was found between the concentrations of 3-hydroxyglutaric acid and 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA). In addition, both 3-hydroxyglutaric acid and MBTCA were strongly correlated with malic acid, indicating a similar formation pathway of these compounds in the tropical region. This study also suggests that isoprene and α/β-pinene oxidation products contribute almost equally to organic carbon (OC) in tropical India.2010-03-30T15:00:00ZFu, PingqingKawamura, KimitakaPavuluri, Chandra M.Chen, JingSwaminathan, T.Polar organic tracers of isoprene, α/β-pinene and β-caryophyllene photooxidation in tropical Indian aerosols (PM10) collected at Chennai were measured using gas chromatography/mass spectrometry. All the biogenic secondary organic aerosol (SOA) tracers showed diurnal variations with higher concentrations at daytime, which is in agreement with the fact that they are photochemical oxidation products of biogenic volatile organic compounds (VOCs). Total concentration ranges of the organic tracers were 18.3-107 ng m^[-3] in summer versus 2.69-66.9 ng m^[-3] in winter. Most of the SOA tracers showed higher concentrations in summer than in winter, while β-caryophyllinic acid, a tracer for β-caryophyllene, showed no seasonal differences. A good correlation (R2=0.67) was found between the concentrations of 3-hydroxyglutaric acid and 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA). In addition, both 3-hydroxyglutaric acid and MBTCA were strongly correlated with malic acid, indicating a similar formation pathway of these compounds in the tropical region. This study also suggests that isoprene and α/β-pinene oxidation products contribute almost equally to organic carbon (OC) in tropical India.山岳における大気化学観測, その動向と課題 : 小レビュー
http://hdl.handle.net/2115/45166
Title: 山岳における大気化学観測, その動向と課題 : 小レビュー
Authors: 五十嵐, 康人; 直江, 寛明; 高橋, 宙; 猪股, 弥生
Abstract: 大気エアロゾルおよび関連する前駆気体, 微量気体の鉛直構造や, それらの自由対流圏での挙動を知る目的で高所山岳を利用した観測研究に興味がもたれる. 我が国における研究の進展に資するため, 最近の世界の高所山岳における大気化学観測研究の動向についてごく簡単な概観を試みた. 観測ロジスティクスや維持の困難性にもかかわらず, 山岳を利用した研究の数は増えているように思われる. 多くの研究では, 気候変動に関わる大気化学の変動に興味の焦点がおかれ, 長期変動データを取得する上で, どのようにバックグラウンドデータを取得するかという観点から, 山岳に特有な気象現象による変動が扱われている. そこで, 山谷風という局地気象による大気質の変動や,「山岳ポンプ」による境界層汚染空気の自由対流圏への輸送について取り扱った研究を主に紹介した. 後者は, 人為汚染気塊を風下域へ拡散させる(長距離輸送)実質的な役割を担っている可能性もある.; Atmospheric chemistry and aerosol observations at mountainous platforms are interested as a way to obtain vertical profiles or free tropospheric information of the concerned aerosols and chemical trace species. In order to facilitate such researches in Japan, recent research trends in atmospheric chemistry at high altitude sites over the world are reviewed. In spite of the difficulties in logistics and maintenance, the utilization of mountain platforms in the atmospheric research seems growing. Concerns are mostly placed on the global atmospheric change in relation to the climate study thus the temporal changes of atmospheric species along with those of meteorological dynamics are reported in many studies. Effects by the local wind circulation, which is characteristic meteorology to the mountain range, on the time series of atmospheric chemistry are described. Also, the venting of polluted boundary layer air into the free troposphere by the thermally induced air flow is discussed. Such venting occurring at mountains beside the industrial region may play a substantial role in a large-scale pollution outflow into the far down-wind regions.2010-03-30T15:00:00Z五十嵐, 康人直江, 寛明高橋, 宙猪股, 弥生大気エアロゾルおよび関連する前駆気体, 微量気体の鉛直構造や, それらの自由対流圏での挙動を知る目的で高所山岳を利用した観測研究に興味がもたれる. 我が国における研究の進展に資するため, 最近の世界の高所山岳における大気化学観測研究の動向についてごく簡単な概観を試みた. 観測ロジスティクスや維持の困難性にもかかわらず, 山岳を利用した研究の数は増えているように思われる. 多くの研究では, 気候変動に関わる大気化学の変動に興味の焦点がおかれ, 長期変動データを取得する上で, どのようにバックグラウンドデータを取得するかという観点から, 山岳に特有な気象現象による変動が扱われている. そこで, 山谷風という局地気象による大気質の変動や,「山岳ポンプ」による境界層汚染空気の自由対流圏への輸送について取り扱った研究を主に紹介した. 後者は, 人為汚染気塊を風下域へ拡散させる(長距離輸送)実質的な役割を担っている可能性もある.
Atmospheric chemistry and aerosol observations at mountainous platforms are interested as a way to obtain vertical profiles or free tropospheric information of the concerned aerosols and chemical trace species. In order to facilitate such researches in Japan, recent research trends in atmospheric chemistry at high altitude sites over the world are reviewed. In spite of the difficulties in logistics and maintenance, the utilization of mountain platforms in the atmospheric research seems growing. Concerns are mostly placed on the global atmospheric change in relation to the climate study thus the temporal changes of atmospheric species along with those of meteorological dynamics are reported in many studies. Effects by the local wind circulation, which is characteristic meteorology to the mountain range, on the time series of atmospheric chemistry are described. Also, the venting of polluted boundary layer air into the free troposphere by the thermally induced air flow is discussed. Such venting occurring at mountains beside the industrial region may play a substantial role in a large-scale pollution outflow into the far down-wind regions.大気汚染と森林
http://hdl.handle.net/2115/45165
Title: 大気汚染と森林
Authors: 松本, 潔; 井川, 学
Abstract: 酸性沈着物の森林への沈着とその樹木への影響に関するこれまでの研究成果を概観し, 続いて著者らが行った丹沢大山における大気化学観測と, この結果をもとにこの地域への酸性沈着物の沈着状況について紹介する. あわせて, 大気圏・生物圏相互作用系の研究における, 酸性沈着物の森林への沈着に関する研究の重要性について考察する.; This paper reviews previous researches concerning acid deposition on forests, and then introduces our recent observations of atmospheric chemical species and their deposition on canopies at forested sites in Mt. Oyama. We also suggest the importance of acid deposition on forests in discussing the atmosphere-biosphere interaction system.2010-03-30T15:00:00Z松本, 潔井川, 学酸性沈着物の森林への沈着とその樹木への影響に関するこれまでの研究成果を概観し, 続いて著者らが行った丹沢大山における大気化学観測と, この結果をもとにこの地域への酸性沈着物の沈着状況について紹介する. あわせて, 大気圏・生物圏相互作用系の研究における, 酸性沈着物の森林への沈着に関する研究の重要性について考察する.
This paper reviews previous researches concerning acid deposition on forests, and then introduces our recent observations of atmospheric chemical species and their deposition on canopies at forested sites in Mt. Oyama. We also suggest the importance of acid deposition on forests in discussing the atmosphere-biosphere interaction system.夏季の西部北太平洋上における海洋生物起源有機エアロゾルの粒径分布
http://hdl.handle.net/2115/45164
Title: 夏季の西部北太平洋上における海洋生物起源有機エアロゾルの粒径分布
Authors: 宮﨑, 雄三; 河村, 公隆; 澤野, 真規
Abstract: 海洋生物生産の活発な時期における海洋大気エアロゾル中の有機物組成と生物起源の寄与を明らかにすることを目的として, 外洋域における有機炭素および有機態窒素の質量粒径分布測定を行った. 本稿では, その結果について解説する. 夏季の西部北太平洋での有機エアロゾルの放出源として海洋生物の影響が大きく, その組成は有機態窒素に富むことが明らかになった. 安定炭素同位体比の分析から, 本研究海域でのエアロゾル全炭素に占める海洋生物起源の割合は46-72%と見積もられた.; Size-segregated aerosol samples were collected over the western North Pacific in the summer of 2008 for the measurements of organic nitrogen (ON) and organic carbon (OC). ON and OC showed bimodal size distributions and their concentrations showed positive correlation with those of biogenic tracers, methanesulfonic acid and azelaic acid. We found that average ON and OC concentrations were twice greater in aerosols obtained in the oceanic region with higher biological productivity than with lower biological productivity. The average ON/OC ratios are higher (0.49±0.11) in more biologically influenced aerosols than those (0.35±0.10) in less biologically influenced aerosols. Stable carbon isotopic analysis indicates that marine-derived carbon accounted for ~46-72% of total carbon in more biologically influenced aerosols. These results provide evidence that organic aerosols in this region are enriched in ON that is linked to oceanic biological activity and the subsequent emissions to the atmosphere.2010-03-30T15:00:00Z宮﨑, 雄三河村, 公隆澤野, 真規海洋生物生産の活発な時期における海洋大気エアロゾル中の有機物組成と生物起源の寄与を明らかにすることを目的として, 外洋域における有機炭素および有機態窒素の質量粒径分布測定を行った. 本稿では, その結果について解説する. 夏季の西部北太平洋での有機エアロゾルの放出源として海洋生物の影響が大きく, その組成は有機態窒素に富むことが明らかになった. 安定炭素同位体比の分析から, 本研究海域でのエアロゾル全炭素に占める海洋生物起源の割合は46-72%と見積もられた.
Size-segregated aerosol samples were collected over the western North Pacific in the summer of 2008 for the measurements of organic nitrogen (ON) and organic carbon (OC). ON and OC showed bimodal size distributions and their concentrations showed positive correlation with those of biogenic tracers, methanesulfonic acid and azelaic acid. We found that average ON and OC concentrations were twice greater in aerosols obtained in the oceanic region with higher biological productivity than with lower biological productivity. The average ON/OC ratios are higher (0.49±0.11) in more biologically influenced aerosols than those (0.35±0.10) in less biologically influenced aerosols. Stable carbon isotopic analysis indicates that marine-derived carbon accounted for ~46-72% of total carbon in more biologically influenced aerosols. These results provide evidence that organic aerosols in this region are enriched in ON that is linked to oceanic biological activity and the subsequent emissions to the atmosphere.