ハインリッヒ事件の際に南極下海の生産性の向上
Julian P Sachs1, Robert F Anderson
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room E34-254, Cambridge, Massachusetts 02139, USA. jsachs@mit.edu
Nature
|April 29, 2005
まとめ
ハインリッヒ現象として知られる北半球からの巨大な氷山の放出は,南洋の藻類の生産性の増加と相関していた. これは,氷河期の気候変化の間に地球規模の海洋循環の変化を示唆しています.
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
- 海洋学 海洋学 海洋学
- 気候科学 気候科学
背景:
- ハインリッヒ現象は,北半球の氷床から大量に氷山が放出され,最後の氷河期の寒冷期を表しています.
- 北大西洋の気候と循環に及ぼす影響は十分に文書化されていますが,この地域を超えた影響は不明です.
研究 の 目的:
- 北半球のハインリッヒ・イベントが亜極南洋に及ぼす影響を調査する.
- 北大西洋の気候の乱れと南洋の生産性の間のテレコネクションを理解する.
主な方法:
- 分子藻の生産性指紋の分析.
- 放射性同位体トレーサーを用いて沈殿パターンを研究する.
- 過去7万年にわたる古海洋学記録の年代測定.
主要な成果:
- 南洋の生産性が上昇した8つの異なる期間が特定されました.
- これらの生産性イベントは,北半球のハインリッヒイベント (1,000〜2,000年以内に) に密接に続いた.
結論:
- 北半球のハインリッヒ事件は,南洋の生産性に大きな変化を引き起こした可能性がある.
- 潜在的なメカニズムは,地球規模の海洋循環の変化,鉄供給,季節的層分化などである.
- 南洋の反応を理解することは,過去と将来の気候変動における海洋の役割を理解するために不可欠です.
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