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Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
北大西洋の内部の経路は,北大西洋のメリディナルの転覆循環である
Amy S Bower1, M Susan Lozier, Stefan F Gary
1Department of Physical Oceanography, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02540, USA. abower@whoi.edu
Nature
|May 16, 2009
まとめ
気候変動のシグナルは,Deep Western Boundary Currentだけでなく,海内経路を通って海中を移動しています. これらの経路を理解することは,将来の気候変動の影響を予測する鍵です.
科学分野:
- 海洋学 海洋学とは
- 気候科学 気候科学
- 物理海洋学 物理海洋学
背景:
- 地球規模の海洋は熱と二酸化炭素の主要な貯蔵庫であり,気候変動に影響を与えています.
- ラブラドール海水 (LSW) は,北大西洋で形成された気候変動の敏感な指標です.
- ディープ・ウエスタン・ボーダー・ストリーム (DWBC) は,LSW輸出の主要な経路であると信じられていた.
研究 の 目的:
- 気候変動の経路と速度を決定するために,地球規模の海洋における信号伝送.
- ラブラドール海水 (LSW) の形成地からの輸出の支配的な経路を調査する.
主な方法:
- 北大西洋の西側の境界に沿った水文観測の分析.
- 地下RAFOS浮遊物を追跡し,2003年から2005年にかけて2年間放出された.
- 模擬モデルでシミュレートされた"e-floats"を使用して,サブポーラーDWBCで放出されます.
主要な成果:
- 最近,サブトロピックスに侵入するLSWは,DWBCではなく,内部の経路に従っています.
- 内部経路への特定の注入ポイントは,グランドバンクの近くで特定されました.
- RAFOSの浮遊軌跡とモデルのシミュレーションにより,以前に過小評価されていたこれらの内陸ルートが明らかになりました.
結論:
- DWBCは,赤道へのLSW輸出の支配的な経路ではありません.
- 内部経路は,深海の換気と熱/炭素輸送において重要な役割を果たしています.
- 内部の亜熱帯回転は,大西洋南極の転覆循環を理解するために不可欠です.
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