衛星高度計データから推論された深海における潮エネルギーの大幅な分散
1College of Oceanic and Atmospheric Sciences, Oregon State University, Corvallis 97331, USA. egbert@oce.orst.edu
Nature
|June 24, 2000
まとめ
海の潮は,浅い海だけでなく,深い海にもかなりのエネルギーを消耗します. 海底の地形によって引き起こされるこの深海の潮の消去は,海洋の混合と熱ハリン循環に大きく寄与する.
科学分野:
- 海洋学 海洋学 海洋学
- 地質物理学 地質物理学とは地質物理学です.
- 流体力学 流体力学とは
背景:
- 海洋の潮は,月の歴史と海洋の混合に意味を持つエネルギー消耗の主要な源である.
- 歴史的に見ると,潮のエネルギー消耗は,主に浅い海における底摩擦に起因していた.
- 証拠は,海底の地形によって生成された内部波を通じて,オープンオーシャンでの消去を示唆したが,推定は様々であった.
研究 の 目的:
- 海洋における潮エネルギーの消耗を実証的にマッピングし,定量化する.
- 深海の潮の消去が,海洋の混合に与える影響を決定する.
主な方法:
- Topex/Poseidonの衛星高度計データを活用した.
- 経験的にマッピングされた潮エネルギー散布パターンが,地球規模の海洋全体に広がっています.
主要な成果:
- 約1テラワット (TW) の潮エネルギー,つまり総消耗量の25-30%が深海に発生する.
- 深海の消散は,粗な海底地形のある地域の近くに集中しています.
- 潮の消耗は,大規模な海洋熱ハリン循環に必要なエネルギーの半分を提供することができる.
結論:
- 深海の潮の消耗は,浅瀬の消耗に匹敵する,重要なエネルギーシンクです.
- 潮によるエネルギーの消耗は,海洋の混合と熱ハリン循環を推進する上で重要な役割を果たします.
- この発見は,海洋エネルギー予算とダイナミクスの理解を修正するものである.
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