最後の氷河期の終結期中に北太平洋の深水形成
Y Okazaki1, A Timmermann, L Menviel
1Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushima-cho, Yokosuka 237-0061, Japan.
まとめ
最後の氷河期の終焉の間,北大西洋の循環が弱まり,深層水形成が北太平洋に移動した. この海洋循環の変化は,地球規模の熱伝送を調節した.
科学分野:
- パレオセアノグラフィー
- 気候科学 気候科学
- 海洋学 海洋学とは
背景:
- 大西洋南極転覆循環 (AMOC) は,北半球の氷床の融水により17,500〜15,000年前に著しく弱まった.
- このAMOCの弱まりは,南極と北太平洋に影響を及ぼし,世界的な影響を及ぼしました.
研究 の 目的:
- "最後の氷河期の終結"の間に北太平洋が深水形成に果たした役割を調査する.
- 海洋熱伝送の変化が地球全体に与える影響を理解するため.
主な方法:
- 北太平洋のパレオ表面プロキシデータの分析.
- 海洋放射性炭素年代換気記録のまとめ.
- グローバル気候モデルシミュレーション.
主要な成果:
- 証拠によると,最後の氷河期の初期に北太平洋で2500〜3000メートルの深さで深い水の形成が起こったことが示唆されています.
- 北大西洋と北太平洋の間には,深い水の形成位置の顕著な切り替えが起こった.
結論:
- 北太平洋は,この期間に深い水の形成に重要な役割を果たしました.
- 観測された深水形成のスイッチは,最後の氷河期終結の間,極に向かっての海洋熱輸送を調節する鍵でした.
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