中大西洋山脊の頂上では,下部熱線線水の激しい混合が起こっています
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Updated: May 5, 2026
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Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
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Louis C St Laurent1, Andreas M Thurnherr
1Department of Oceanography, Florida State University, Tallahassee, Florida 32306, USA. stlaurent@ocean.fsu.edu
Nature
|August 10, 2007
まとめ
地球の循環に不可欠な海洋の乱れは,中大西洋のの狭い通路で発生します. これらの場所は,重要な浮力フックスを生み出し,地球規模で海洋の混合に影響を与えます.
科学分野:
- 海洋学 海洋学 海洋学
- 流体力学 流体力学とは
- 地質物理学 地質物理学とは地質物理学です.
背景:
- 深層と上層の海洋層の浮力交換は,地球規模の海洋循環に不可欠です.
- この交換の主なメカニズムは乱流混合であるが,その分布は十分に理解されていない.
- 内部波の不安定性と流動の地形的な方向化は,乱流に影響を与える重要なプロセスです.
研究 の 目的:
- 地形学的な特徴,特に大西洋中部の山脊の経路が,海洋の乱流を生成する役割を調査する.
- これらのエネルギーに満ちた海洋地域における乱流と結果として生じる浮力フックスを定量化するために.
- 中洋のの通路で発生する乱流の世界的な重要性を評価する.
主な方法:
- 海洋の乱流と拡散性のインサイト測定.
- 亜熱帯北大西洋のミッド・アトランティック・リッジの頂上で行われた観測.
- 溝渓谷や山脊・横渓谷を通る流れの動態の分析.
主要な成果:
- 中大西洋のリフト渓谷と峡谷の通路は,海洋の乱流のために非常にエネルギッシュな場所として特定されています.
- 0.03 m2 s ((-1) までの拡散性は,スリールの下流で測定され,典型的な熱線と深淵値を大幅に上回りました.
- これらの通路からのオーバーフローは,ロマンシェ断層地帯のような主要な海洋特有の浮力流に相当する浮力流に大きく貢献します.
結論:
- 中洋の山脊の狭い通路で発生する乱れは,世界の海洋循環を推進する上で重要な役割を果たします.
- これらの地形学的な特徴は,海洋浮力フルースの有意で,以前は過小評価されていた源である.
- これらの地域の乱流を理解することは,正確な海洋モデリングと気候予測に不可欠です.
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