北極の表面,雲,宇宙からの放射線の特性に関する最近の動向
1Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin-Madison, 1225 West Dayton Street, Madison, WI 53706, USA. xuanjiw@ssec.wisc.edu
Science (New York, N.Y.)
|March 15, 2003
まとめ
北極の温暖化傾向は,春と夏の曇り空が増加し,冬は曇り空が少なく冷却していることを示しています. 季節的な雲の変化は,大規模な大気循環パターンに関連して,表面温度に影響します.
科学分野:
- 気候科学 気候科学
- 大気物理学 大気物理学
- リモートセンシング (リモートセンサー)
背景:
- 北極地域は,気温,アルベド,雲の覆いによって影響される複雑な気候ダイナミクスを示しています.
- 北極の雲の性質の季節的変動を理解することは,気候モデリングに不可欠です.
研究 の 目的:
- 1982年から1999年までの衛星による北極の雲と地表の特性の動向を分析する.
- 観測された北極の気候変化に対する放射線バランスと大気循環の影響を調査する.
主な方法:
- 衛星データを活用して北極上の雲と表面の特性を導き出しました.
- 1982年から1999年にかけてのタイムトレンドを分析した.
- 観測された変化が,北極振動指数と相関している.
主要な成果:
- 観測された北極の温暖化は,春/夏に曇りが増加し,寒冷化は,冬に曇りが減少した.
- 春の雲の上昇は,放射的にバランスのとれた表面温度とアルベドの変化です.
- 夏,秋,冬の雲の強制は,冷却の傾向を示し,これらの変化なしに増幅された温暖化を示唆しました.
結論:
- 季節的な雲の変動は,北極の表面温度変化を調節する上で重要な役割を果たしています.
- 観測された北極の気候の傾向は,局所的なプロセスではなく,大規模な大気循環 (北極振動) と強く関連しています.
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