海洋エアロゾールへの生物学的要因による有機的貢献
Colin D O'Dowd1, Maria Cristina Facchini, Fabrizia Cavalli
1Department of Experimental Physics and Environmental Change Institute, National University of Ireland, Galway, Ireland.
Nature
|October 8, 2004
まとめ
海洋有機物質は,プランクトンの開花中に亜マイクロメートルのエアロゾール質量を支配することによって,気候に大きく影響します. この有機エアロゾールは,雲の性質に影響を与え,エアロゾール-雲-気候フィードバックシステムの重要な要因です.
科学分野:
- 大気化学 大気化学
- 海洋学 海洋学とは
- 気候科学 気候科学
背景:
- 海洋エアロゾールは地球のアルベドと気候に大きな影響を与えます.
- 既存の研究は主に海塩と海塩以外の硫酸塩に焦点を当てており,有機的貢献は不明である.
- サブマイクロメートルの海洋エアロゾール質量は,しばしば,無機種だけで説明できる量を上回ります.
研究 の 目的:
- サブマイクロメートルの海洋エアロゾールの物理的,化学的特性を調査する.
- オーガニックマターの海洋エアロゾール質量への貢献を,さまざまなサイズで定量化するために.
- 海洋有機アエロソルの水性または水害性の性質を決定する.
主な方法:
- 北大西洋上空で行われたフィールド実験.
- 春から秋までのプランクトンの開花期に採られた測定値.
- 有機分数と水溶性を含むエアロゾールの物理的,化学的性質の分析.
主要な成果:
- オーガニック物質は,花期中に亜マイクロメートルの海洋エアロゾール質量 (63%) を支配しました.
- 有機分子の約45%は水に溶けず,18%は水に溶けました.
- 生物学的活動が低かった冬の間,有機分子は15%まで減少した.
結論:
- 海洋有機エアロゾールは,エアロゾール-雲-気候フィードバックにおいて重要な役割を果たします.
- 有機物質は,雲の水滴の濃度 (15%から100%以上) を大幅に高めることができます.
- 海洋有機エアロゾールの組成と性質を理解することは,正確な気候モデリングに不可欠です.
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