炭酸塩の堆積,気候の安定性,そしてネオプロテロゾーイク氷河期
Andy J Ridgwell1, Martin J Kennedy, Ken Caldeira
1Department of Earth Sciences, University of California-Riverside, Riverside, CA 92521, USA. andyr@citrus.ucr.edu
Science (New York, N.Y.)
|November 1, 2003
まとめ
プランクトンのカルシファーはファネロゾーイク時代に進化し,海洋炭酸をバッファリングすることで気候を安定させました. これは,プレキャンブリアの炭素循環とは異なり,海洋化学を保存しています.
科学分野:
- 地質化学 地質化学
- 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,古代気候学 (paleoclimatology) とは
- 海洋学 海洋学とは
背景:
- プレカンブリア期の炭素循環は,浅水環境とCO2気候フィードバックに敏感であり,ネオプロテロゾイク氷河期に至った.
- プレカンブリア気候バッファリングは,大陸の気象インプットをバランスする浅瀬の炭酸塩堆積に依存していました.
- プランクトンのカルシファーの進化は,地球の気候の調節に重大な変化をもたらした.
研究 の 目的:
- ファネロゾイク期の気候システムの安定化を説明するために.
- 海洋の炭酸イオン濃度をバッファリングするプランクトカルシファーの役割を明らかにする.
- ネオプロテロゾーイク氷河期とキャップ炭酸塩の形成の原因を理解するために.
主な方法:
- 海底の堆積物における炭酸塩保存の分析.
- 海洋炭酸イオン濃度ダイナミクスのモデリング.
- プレカンブリアとファネロゾーイクにおける炭素循環過程の再構築.
主要な成果:
- プランクトンの化器は,飽和度に依存した炭酸塩の保存を導入し,海洋化学をバッファリングしました.
- この新しいメカニズムは,ファネロゾーイク期の気候システムを安定させました.
- プレカンブリア時代の気候の不安定さは,このバッファリングメカニズムの欠如と関連しています.
結論:
- プランクトンのカルシファーの進化は,気候の安定化にとって重要な出来事でした.
- 飽和度に依存する炭酸塩の保存は,長期的な気候規制の重要な要素である.
- 過去の炭素循環のダイナミクスを理解することは,地球システムの感受性に関する私たちの知識を伝える.
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