短命の天然ハロゲンは,気候に間接的な冷却効果を発揮する
Alfonso Saiz-Lopez1, Rafael P Fernandez2,3, Qinyi Li2,4
1Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Madrid, Spain. a.saiz@csic.es.
Nature
|June 28, 2023
まとめ
海から放出される短命のハロゲンは 大気の大幅な冷却を引き起こします 人間の活動によって増幅された この冷却効果は 工業化以前の時代から増加し 地球の放射能バランスに影響を与えています
科学分野:
- 大気化学
- 気候科学
- 放射性フォッシング
背景:
- 海から放出される短命のハロゲンは 大気中に存在します
- 自然のハロゲン排出量は 工業化以前の時代から 人為的な活動によって増幅されています
- 人為的な短命のハロ炭素も大気中に放出されます.
研究 の 目的:
- 地球の放射能バランスに 短命のハロゲンの影響を 量化するために
- この放射線効果の過去の変化と将来の予測を評価する.
主な方法:
- 観測証拠と大気モデリングを用いて 放射性波動を決定した.
- ハロゲン,オゾン,メタン,エアロゾール,平流水蒸気の間接的な放射線効果を計算した.
主要な成果:
- 短命のハロゲンは,平方メートルあたり -0.13 ± 0.03ワットの実質的な間接的な冷却効果を発揮します.
- この冷却は部分的にメタン,エアロゾール,そして平流層の水蒸気による温暖化によって相殺されます.
- 1750年以来,自然ハロゲン放出量の人為的な増幅により,冷却効果は61%増加しました.
結論:
- 短命のハロゲンの間接的な放射性効果は重要で,歴史的に増加しています.
- この影響の将来の変化は,気候予測と社会経済発展に依存しています.
- この効果を気候モデルに組み込むことは,地球の気候システムの現実的なベースラインに不可欠です.
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