アマゾンの境界層のエアロゾール濃度は,降雨中の垂直輸送によって持続する.
Jian Wang1, Radovan Krejci2, Scott Giangrande1
1Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
Nature
|November 4, 2016
まとめ
大気中の蒸気は 新しいエアロゾール粒子を 核化する アマゾンでは 降水によって これらの粒子が 自由な熱帯圏から 境界層に移動し 雲の性質に影響を与えます
科学分野:
- 大気科学
- エアロゾール科学
- 雲の物理
背景:
- 大気蒸気の核化は,雲の凝縮核 (CCN) に不可欠な新しいエアロゾール粒子を形成します.
- 大陸のエアロゾール研究はしばしば人為的な影響を受け,原始的な環境は研究されていない.
- アマゾンの熱帯雨林は 自然に近いエアロゾール処理を 研究するためのユニークな環境です
研究 の 目的:
- アマゾンの境界層の小粒子の起源を調査する
- 原始的な環境で 雲の形成に影響を与える 粒子の集団を維持する過程を理解する
主な方法:
- 雨季中にアマゾンの中央部で実施された航空機と地上での測定.
- エアロゾール粒子の濃度と 清潔な大気条件下での垂直輸送メカニズムに焦点を当てます
主要な成果:
- 小型のエアロゾール粒子の高濃度 (直径 < 50 nm) は,下部フリートロポスフィアで観察されました.
- コンベクティブ・ダウンドラフトとストラティフォーム・リージョン・ダウンドラフトを含む降雨現象は,主要な輸送メカニズムとして特定されました.
- この過程で 粒子は 自由気流から アマゾンの境界層へと移動します
結論:
- 降水中のエアロゾール粒子の急速な垂直輸送は,アマゾンの境界層の粒子の集団を維持します.
- このメカニズムは,エアロゾールと雲の相互作用と,自然の地上の環境における気候の調節を理解するために不可欠です.
- この発見は 根本的な大気過程を研究するために 原始的な環境の重要性を強調しています
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