外部の力なしのカップリングされた海洋-大気シミュレーションにおける突然の気候イベント
1Lamont-Doherty Earth Observatory, Palisades, New York 10964, USA. alexhall@ldeo.columbia.edu
Nature
|February 24, 2001
まとめ
内部大気の変動は,急激な気候変化を引き起こす可能性があります. 1万5千年の地球循環シミュレーションにより,北大西洋における自発的な冷却現象が明らかになり,それは淡水の強制ではなく,風によって引き起こされた.
科学分野:
- 気候科学 気候科学
- 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
- 海洋学 海洋学 海洋学
背景:
- 北大西洋の気候再構築は,氷河期とホロケーン期の間に頻繁に突然の変動を示しています.
- 以前の気候モデルでは,このような現象をシミュレートするために淡水強制が必要でした.
- これらの急速な気候変動の根本的な原動力は不明である.
研究 の 目的:
- 北大西洋の急激な気候変動を誘発する大気中の内部変動の可能性を調査する.
- 外部の強制なしに急激な冷却イベントをシミュレートするために.
主な方法:
- 現在の気候条件を用いて,1万5千年の地球循環シミュレーションを行った.
- 自発的な気候現象とその要因について,シミュレーション出力を分析した.
主要な成果:
- グリーンランド南部の近くで発生した自発的な深刻な冷却現象は,平均より6〜10標準偏差低い温度で30〜40年間続いた.
- このイベントは,北西風が北大西洋に冷たい淡水を運ぶため引き起こされた.
- 海洋のコンベクションが停止し,上層の海洋層の冷却を局所的にしました.
結論:
- 内部大気変動だけでは,北大西洋で極端な気候の乱れを引き起こす可能性があります.
- シミュレーション結果は,急速な冷却の観測記録と一致しています.
- これは,外部トリガーのない過去の急激な気候変動の潜在的なメカニズムを示唆しています.
関連する概念動画
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