大量の原子塩素源は,大陸中部の反応性窒素化学から推測された
Joel A Thornton1, James P Kercher, Theran P Riedel
1Department of Atmospheric Sciences, University of Washington, Seattle, Washington 98195, USA. thornton@atmos.washington.edu
Nature
|March 12, 2010
まとめ
中央大陸での観測は,塩素原子の前駆体であるニトリル塩化物が,海岸から遠くで生成されていることを明らかにしています. これは,大気中の塩素の有意な源を示唆しており,これは,潜在的に人為的な汚染によるものである.
科学分野:
- 大気化学 大気化学
- 環境科学 環境科学
背景:
- ハロゲン原子と酸化物は,大気の組成と化学に影響を及ぼします.
- 塩素原子は,水銀とメタンの寿命に影響を与え,オゾン循環に影響を与えます.
- ガスの塩素前駆体は,通常,海洋環境と関連しています.
研究 の 目的:
- 塩素原子の前駆体であるニトリル塩化物の大陸中部の観測を報告する.
- 沿岸地域から離れた内陸のニトリル塩化物の生産を調査する.
- トロポスフィアの塩素に対する人為的な汚染物質の寄与を評価する.
主な方法:
- 中央大陸の場所でのニトリル塩化物およびその前駆物のインサイト測定.
- 観測データとモデル予測を比較する.
- エアロゾールと降水成分に関する長期モニタリングデータの分析.
主要な成果:
- 海岸から1,400km離れた場所で,持続的で有意なニトリル塩化物産生が観察されました.
- 隣接する米国で観察されたニトリル塩化物の生産は,世界の沿岸の推定値と比較できます.
- トロポスフィアの塩素原子の大部分は,人為的な汚染物質から発生している可能性があります.
結論:
- ニトリル塩化物の生産は,沿岸部や海域に限定されていません.
- 内陸のニトリル塩化物の生産は,以前過小評価されていた大気中の塩素の重要な源である.
- 人為的な汚染物質は,トロポスフィアの塩素循環において重要な役割を果たす可能性がある.
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