2020年に地球全体の酸化が減少した証拠の収束
Wei Chen1,2,3, Yuzhong Zhang2,3, Ruosi Liang1,2,3
1College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
National science review
|August 21, 2025
まとめ
全世界のヒドロキシルラジカル (OH) の濃度は2020年に減少し,メタン予算に影響を与えました. 減少は北半球におけるCOVID-19のロックダウンと南半球におけるオーストラリアの火災に関連していた.
科学分野:
- 大気化学
- 気候科学
- 環境科学
背景:
- 水酸化基 (OH) は,メタンや他のガスの大気中酸化の鍵です.
- 年間OH濃度の変化はよくわかっていないため,メタン予算の分析が困難である.
研究 の 目的:
- 全世界のヒドロキシルラジカル (OH) 濃度における2020年の異常を調査する.
- 2020年のイベントがOHレベルと大気中の酸化に与える影響を決定する.
主な方法:
- 衛星による一酸化炭素 (CO) 観測を用いて,ゾナルのOH分布を推論する新しい方法を開発した.
- メタン,メチルクロフォーム,そして大気圏オゾンの観測を分析した.
- OH異常を説明するために大気化学のシミュレーションを利用した.
主要な成果:
- 全世界のOH濃度は2018年から2019年に比べて2020年に4.0%±0.9%減少した.
- 北半球 (2.4% ± 1.2%) と南半球 (5.7% ± 1.2%) の両方でOH減少が観察されました.
- 北半球の窒素排出量減少と南半球の火災排出量増加が関連している.
結論:
- 2020年の大気酸化は,人為的および自然現象によって大きく影響された.
- 異なる化学メカニズムは 各半球でOHの減少を促しました
- 発見は,変化する排出シナリオの下で,将来の大気組成に影響を及ぼします.
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