北極の縮小する海氷の覆いの展望
Mark C Serreze1, Marika M Holland, Julienne Stroeve
1Cooperative Institute for Research in Environmental Sciences, National Snow and Ice Data Center, Campus Box 449, University of Colorado, Boulder, CO 80309-0449, USA. serreze@kryos.colorado.edu
Science (New York, N.Y.)
|March 17, 2007
まとめ
北極海氷の面積は,自然変動と温室効果ガスの排出によって引き起こされた1979年から2006年にかけての負の傾向を示しています. この北極の氷の減少は加速し,世界の気候パターンに影響を与える可能性があります.
科学分野:
- 気候科学 気候科学
- 北極研究 アークティック研究
- 海洋学 海洋学 海洋学
背景:
- 北極の海氷の広がりは,1979年から2006年までのすべての月にわたって負の線形傾向を示しています.
- 観測された氷の減少は,氷・海・大気系内の自然な変動と温室効果ガスの放射力強迫の増加に起因する.
- 気候モデルは,観察された傾向との質的一貫性を示し,人為的要因の役割を支持しています.
研究 の 目的:
- 1979年から2006年までの北極海氷の範囲の線形傾向を分析する.
- 北極の氷の減少に自然変動と温室効果ガスの誘発放射力による影響の組み合わせを調査する.
- 季節的に氷のない北極圏への急速な移行の可能性とそのより広範な気候への影響を評価する.
主な方法:
- 1979年から2006年までの月次北極海氷面積データにおける線形動向の分析.
- 観測された傾向を気候モデルからのシミュレーションと比較.
- 結合された氷・海・大気システムの動態の評価.
主要な成果:
- 研究期間中,北極の海氷の広がりの一貫したマイナスの傾向は,毎月観察されました.
- 観測された氷の減少は,自然的な気候の変動と,人類による放射的強制の組み合わせと一致しています.
- 気候モデルは観察された傾向を質的に複製しますが,季節的に氷のない北極のタイミングに関するシミュレーションには大きな分散があります.
結論:
- 北極の海氷は,自然の変動と温室効果ガスの濃度上昇の両方のために減少しています.
- 氷が薄くなるにつれて,季節的に氷のない北極圏への急速な移行は可能であり,潜在的に重大な気候変動につながる可能性があります.
- 北極の氷の減少は,北極の淡水システム,エネルギー予算に影響を及ぼし,中緯度の気象パターンを潜在的に変化させると予想されています.
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