ユーラシアの氷床の増加は,隣接する氷のダム湖によるものです
G Krinner1, J Mangerud, M Jakobsson
1LGGE, CNRS-UJF Grenoble, BP 96, F-38402 Saint Martin d'Hères, France. krinner@ujf-grenoble.fr
Nature
|January 30, 2004
まとめ
大規模なユーラシア原氷河湖は,氷床の融解を減らし,地域の夏の気候を大幅に冷却しました. この冷却は氷床の成長を加速し,崩壊を遅らせ,過去の気候動態に影響を与えた.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 氷河学 氷河学とは
- 大気科学 大気科学
背景:
- 大規模な前氷期湖は,熱容量と大気フィードバックを通じて地域の気候に影響を与えます.
- ユーラシアの氷のダム湖は,約9万年前に形成され,最後の氷河期中にロシアの川を遮断しました.
研究 の 目的:
- ユーラシアの氷河前期湖がバレンツ・カラ氷床に与える影響を調査する.
- これらの湖が氷床の融解と地域の気候に及ぼす影響を定量化するために.
主な方法:
- 大気一般循環モデルを用いた高解像度シミュレーション.
- 氷床表面質量バランスの明示的なシミュレーション.
主要な成果:
- ユーラシア原氷河湖は,ロシアにおける地域的な夏の冷却を大きく引き起こした.
- この冷却は,南の縁で氷床の融解を大幅に減少させた.
- 夏の冷却効果は,湿度低下による降雪量の減少を上回った.
結論:
- 氷河期湖による冷却は,ユーラシアの氷床の成長を加速し,崩壊を遅らせた.
- このメカニズムは,北米の氷床にも影響した可能性がある.
- 氷河前期湖は,氷河の動態と古気候の再構築の重要な要因である.
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