暗くなるから明るくなるまで:地球の表面における太陽放射線の10年にわたる変化
Martin Wild1, Hans Gilgen, Andreas Roesch
1Institute for Atmospheric and Climate Science, Swiss Federal Institute of Technology (ETH), Winter-thurerstrasse 190, CH-8057 Zurich, Switzerland. martin.wild@env.ethz.ch
Science (New York, N.Y.)
|May 10, 2005
まとめ
グローバルダミング,つまり太陽放射線の減少は,1990年代に逆転した. 最近の観測では,広範囲に広がる表面の明るくなり,気候と生態系に影響を及ぼしていることが示されています.
科学分野:
- 環境科学 環境科学
- 大気科学 大気科学
- 気候科学 気候科学
背景:
- 太陽放射線の変動は,地球の環境に大きな影響を与えます.
- 1990年まで表面太陽放射線の減少が記録されていたグローバル・ディミング (Global dimming) は,世界中で観察されました.
- 最近のデータは,この傾向が逆転していることを示している.
研究 の 目的:
- 1990年以降の最近の地表太陽放射線の動向を分析する.
- 1980年代後半から観察された広範囲にわたる表面の明るさの現象を調査する.
- これらの変化が気候と生態系に及ぼす影響を理解する.
主な方法:
- 主に北半球からの,新たに利用可能な表面太陽放射線観測の分析.
- 1990年後のデータと1990年以前のグローバルディミング記録の比較.
- 観測された明るさの調整と大気パラメータの変化.
主要な成果:
- グローバル・ディミング・トレンドは1990年代まで続かなかった.
- 1980年代後半から,広範囲にわたる表面の明るくする傾向が観察されています.
- 観測された明るさは,曇りの変化と大気の伝播と一致しています.
結論:
- グローバルダミングから明るくなる方向への逆転は,大気条件の大きな変化を示唆しています.
- 太陽放射線の変化は,地表の気候,水文循環,氷河,生態系に重大な影響を及ぼします.
- 継続的なモニタリングは,長期的な環境影響を理解するために不可欠です.
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