氷床の変化によって制御される急激な氷河期気候の変化.
Xu Zhang1, Gerrit Lohmann2, Gregor Knorr3
1Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bussestrasse 24, D-27570 Bremerhaven, Germany.
Nature
|August 15, 2014
まとめ
北半球の氷床 (NHIS) の漸進的な変化は,ダンズガード-オシュガー (DO) イベントのような急速な氷河期気候の変化を引き起こす可能性があります. このメカニズムは,千年規模の気候変動の変動と氷河期間の急激な変化を説明します.
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
- 気候モデリング
- 四次期の地質学
背景:
- ダンズガード-オシュガー (DO) イベントとして知られるミレニアムスケールの温暖化イベントは,プレイストセンの氷河期の顕著な特徴です.
- 代理データでは,氷河期中に繰り返される急速な気候変化が明らかになり,80万年前まで遡り,その原因に関する広範な研究を促しました.
研究 の 目的:
- 総合的な気候モデルを使用して,ダンズガード-オシュガー (DO) イベントの生成のための一貫したメカニズムを調査する.
- 北半球の氷床 (NHIS) の高さが,急激な氷河期気候変化を引き起こしている役割を調査する.
主な方法:
- 総合的な完全に結合された大気-海洋-海-氷のモデルを使用した.
- 北半球の氷床 (NHIS) の高度におけるシミュレートされた漸進的な変化.
- 北大西洋の気温,熱帯の雨帯のシフト,南半球の冷却を含む,シミュレーションされたグローバルな気候反応を分析した.
主要な成果:
- NHISの高さの漸進的な変化は,DOイベントに似た急速な氷河気候の変化を引き起こす可能性があります.
- 北大西洋の温暖化や双極性波動などのシミュレーション反応は,経験的証拠と一致しています.
- 2つの氷河海循環状態と北大西洋のポジティブなフィードバックループを含むメカニズムを特定しました.
結論:
- 北半球の氷床 (NHIS) の体積変動は,DOイベントと千年スケールの気候変動の一貫したメカニズムを提供します.
- 急激な気候変動は,海洋循環状態によって促進されるNHISの高さとCO2レベルのわずかな変化によって引き起こされます.
- この研究は,氷河の千年スケールの変動性と急激な気候変動を,中間氷床の動態と関連付けています.
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