氷河の境界における炭素循環と海洋循環の時間的関係
Alexander M Piotrowski1, Steven L Goldstein, Sidney R Hemming
1Lamont-Doherty Earth Observatory and Department of Earth and Environmental Sciences, Columbia University, Palisades, NY 10964, USA. apio04@esc.cam.ac.uk
Science (New York, N.Y.)
|March 26, 2005
まとめ
氷河期における海洋循環の変化に先行した世界的な炭素予算のシフトは,氷床がこれらの移行を牽引した. ミレニアム温暖化現象は一貫したパターンを示せず,海洋循環がいくつかの気候変化を引き起こした可能性があることを示唆しています.
科学分野:
- パレオセアノグラフィー
- 気候科学 気候科学
- 地質化学 地質化学
背景:
- 地球の炭素循環,海洋循環,氷床の動態の相互作用を理解することは,過去の気候変動の再構築に不可欠です.
- 最後の氷河期は,気候の変動が大きいため,これらの相互作用を研究するための重要な期間を提供します.
研究 の 目的:
- 氷河期間の氷河期間のサイクルと急激な温暖化イベントの間の炭素予算のシフト,熱ハリン循環,氷床のダイナミクスの間の時間的関係を調査する.
- 最後の氷河期における気候変動の要因を特定する.
主な方法:
- 南大西洋の高沈着率の深海核の分析.
- 過去の炭素予算と海洋循環パターンの再構築.
主要な成果:
- 地球と南洋の炭素予算の変化は,最後の氷河期の始まりと終わりの間,熱ハリン循環の変化に先行しました.
- 氷床の成長と後退が,それぞれ,これらの炭素と循環の変化を引き起こした.
- 突発的なミレニアム温暖化イベントの間,一貫したリード・ラグ関係が見つかりませんでしたが,海洋循環がミレニアム気候変化を誘発する可能性を示唆しています.
結論:
- 大規模な氷河期と氷河期間の移行は,主に気候変化によって引き起こされ,氷床のダイナミクスを強制し,その後の炭素予算と海洋循環に反応しました.
- ミレニアムスケールのイベントの間の複雑な相互作用は,海洋循環が急激な気候変動に影響を与える可能性を強調しています.
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