北極地域における海氷の厚さの高度の年間変動がある
Seymour Laxon1, Neil Peacock, Doug Smith
1Centre for Polar Observation and Modelling, University College London, Gower Street, London WC1E 6BT, UK. swl@cpom.ucl.ac.uk
Nature
|October 31, 2003
まとめ
北極海の氷の厚さは,主に夏の融解の範囲のために,年々非常に変動します. この変動性は,将来の気温上昇と海氷の変化を予測する気候モデルにとって極めて重要です.
科学分野:
- 気候科学 気候科学
- 結晶圏の研究 結晶圏の研究
- リモートセンシング (リモートセンサー)
背景:
- 北極海氷の変化は,地球温暖化の予測における大きな不確実性です.
- 海氷の厚さの変動を正確に表現することは,気候モデルの検証に不可欠です.
- 以前の研究は数値シミュレーションに頼っており,海氷の厚さに関するシナプティック観測データがなかった.
研究 の 目的:
- 北極海の平均氷の厚さフィールドとその変動性を決定する.
- 数値モデルの結果を観測データで検証する.
- 年間間の海氷の厚さの変化の要因を理解する.
主な方法:
- 北極海氷の厚さの8年間のタイムシリーズを利用した.
- 氷の厚さは,氷のフリーボードの衛星高度計測定から得られた.
- 65°Nから81.5°Nまでの緯度範囲でデータを分析した.
主要な成果:
- 北極海氷の平均厚さの高頻度年間変動が明らかになりました.
- 厚さの変動に影響を与える主要な要因として,夏の融解範囲を特定しました.
- 循環の変化は,融解のダイナミクスと比較して,より小さな役割を果たしていることがわかりました.
結論:
- 北極海の氷の厚さは,夏の融解の範囲によって大きく影響を受けます.
- 融解の季節の長さの増加は,北極海氷のさらなる薄まりを引き起こす可能性が高い.
- 発見は,北極海氷の気候モデル予測を改善するために重要な観測データを提供します.
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