プレイストセンの氷河期における太平洋の深層流入と換気を強めた
I R Hall1, I N McCave, N J Shackleton
1Department of Earth Sciences, Cardiff University, PO Box 914, Cardiff CF10 3YE, UK. Hall@cardiff.ac.uk
Nature
|August 24, 2001
まとめ
南洋の深い水の生産は,地球の熱予算に大きな影響を与えます. 氷河期には太平洋の深層流入が激化し,おそらく南極の底水の形成が増加したためであった.
科学分野:
- * パレオシアノグラフィー
- * 気候科学 気候科学
- * 南洋ダイナミクス
背景:
- *南洋の深水産は,地球温暖化分布に影響を及ぼしている.
- *太平洋への深い水の供給は,主にニュージーランド東の深い西の境界流から来ている.
研究 の 目的:
- * プレイストセーン時代に太平洋の深水特性と流れ速度の変化を再構築する.
- *太平洋の深層流入と南極の地下水の生産との関係を調査する.
主な方法:
- * 深い西部境界流の影響を受けた堆積物核の分析.
- * 過去の深水状態を再構築するために物理的および同位体プロキシの適用.
主要な成果:
- * 過去120万年の氷河期に太平洋の深海への流入と換気が強化された証拠.
- * 観測された深水の流れの変化は,氷河期における南極地底水の生産の増加と相関しています.
- * プレイストセーン中期の気候移行 (0.86〜0.45百万年前) の間に確認された地球熱ハリン循環における重大な乱れ.
結論:
- * 氷河期間の太平洋の深海への強烈な流入は,南洋の風の増加や海氷の形成によって引き起こされる可能性があります.
- *南極の底水の生産は,深海の太平洋循環を調節する重要な要因です.
- * プレイストセンの半ばの気候移行は,世界の海洋循環パターンの大きな変化を象徴しました.
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