微細なエアロゾール粒子による大幅なコンベクションと降水増強

Jiwen Fan¹, Daniel Rosenfeld², Yuwei Zhang^3,4

¹Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA. jiwen.fan@pnnl.gov.

Science (New York, N.Y.)

|January 27, 2018

まとめ

超微細なエアロゾール粒子 (<50 nm) は,新しい雲滴を形成することによって,深層流動雲 (DCC) を活性化することができます. このプロセスは雲の強さを増し気候予測に影響を与えます

科学分野:

大気科学
気候科学
雲の物理

背景:

エアロゾールと雲の相互作用は気候予測における大きな不確実性の源です
超微細なエアロゾール粒子は (<50 nm) 豊富ですが,伝統的に雲形成には重要とは考えられません.
原始的な環境では,効率的なドロップレット凝結により,高超飽和度で深層流動雲 (DCC) が形成される.

研究の目的:

深層流動雲 (DCC) の形成と増強における超微細なエアロゾール粒子 (<50 nm) の役割を調査する.
人為的な汚染がかつての原始的な地域における雲の動態に与える影響を理解するためです

主な方法:

アマゾン上空の深層流動雲 (DCC) の観測データ分析
数値シミュレーションを使用して,雲の形成とエアロゾール-雲の相互作用をモデル化します.

主要な成果:

DCCは低エアロゾール状態で,有意な蒸気過飽和を発生させる.
これらの雲は,汚染の羽根からの超微細なエアロゾール粒子 (<50 nm) を活性化させることができます.
UAPの活性化により,雲滴の形成が増加し,凝縮が強化され,DCCが活性化され,潜在的加熱が増加します.

結論:

超微細なエアロゾール粒子は,深層コンベクト雲 (DCC) の増強に重要な役割を果たします.
人為的な汚染は,このメカニズムを通して,原始的な地域におけるDCCを活性化することができます.
この発見は,エアロゾールと雲の相互作用の不確実性を減らすことで,気候予測を改善する上で重要な意味を持つ.

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