ウェイルの氷河論は,ノルウェー核K11の同位体研究によって裏付けられている
まとめ
最後の氷河期の間,ノルウェー海底の水は暖かく,北大西洋の深い水と似ていた. これは,ノルウェー海が,北大西洋の深い水が侵入できるように,密度の高い地表水槽ではなかった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
- 海洋地質学 海洋地質学
- 気候科学 気候科学
背景:
- 過去の海洋循環を理解することは,将来の気候変動を予測する上で極めて重要です.
- 地球の歴史を通して,世界の海洋循環におけるノルウェー海の役割は様々でした.
研究 の 目的:
- 最後の氷河期におけるノルウェー海底水の物理的パラメータを再構築する.
- 氷河期におけるノルウェー海底水の源を特定するために.
主な方法:
- 酸素-18 (O-18) 分析は,ペラジックおよびベンティック型フォラミニフェラで行われました.
- コアK11のフォラミニフェラを分析して,過去の海洋状態を決定した.
主要な成果:
- 氷河期ノルウェー海底の水は,現在の条件よりも暖かかった.
- 氷河のノルウェー海底水の物理的パラメータ (温度,O-18比,塩分) は北大西洋の深い水と一致しました.
- ノルウェー海は,最後の氷河期の間,密度の高い地表水のシンクとして機能しなかった.
結論:
- 北大西洋の深い水は,氷河期中にノルウェーの深い盆地に侵入しました.
- ノルウェー海の循環パターンは,氷河期と氷河間期の間に大きく異なっていた.
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