Argoが観測したマッデン-ジュリアン振動の深海の衝撃は,Argoの浮遊物によって観測されました
Adrian J Matthews1, Patama Singhruck, Karen J Heywood
1School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK. a.j.matthews@uea.ac.uk
Science (New York, N.Y.)
|December 15, 2007
まとめ
マッデン-ジュリアン振動 (MJO) は,熱帯深海に大きく影響を及ぼし,大規模なケルビン波を引き起こします. この発見は,大気パターンと深海のダイナミクスとの間の重要なつながりを明らかにしています.
科学分野:
- 海洋学 海洋学とは
- 大気科学 大気科学
- 気候のダイナミクス
背景:
- マッデン-ジュリアン振動 (MJO) は,熱帯天候の変動の主な要因である.
- MJOが深海に及ぼす影響を理解することは,気候モデリングに不可欠です.
- 以前の研究は,主にMJOの大気成分に焦点を当てていた.
研究 の 目的:
- MJOの深い熱帯海の構成要素の決定的な証拠を提供するために.
- MJOに関連する風のストレス異常によって引き起こされる海洋ケルビン波を調査するために.
- MJOに関連した深海の異常の振幅を定量化する.
主な方法:
- Argoのプロファイリングの配列のデータを活用して浮動する.
- グローバル海洋の上部2000メートルの前例のない時空のカバーを分析する.
- 表面風のストレス異常とその影響が海洋ケルビン波に及ぼす影響を調査する.
主要な成果:
- MJOの深い熱帯海洋成分が確認されました.
- 1500メートルまで広がる東へ広がる海洋赤道ケルビン波を特定した.
- 観測された深海の異常振幅は,年間サイクル振幅の最大6倍である.
結論:
- MJOは,ケルヴィン波を通して,海底の大幅な変動を引き起こします.
- この深海のエネルギーシンクは,エルニニョ-南方振動 (ENSO) を理解するために不可欠です.
- 発見は,深海の測定を解釈し,気候予測を改善するのに役立ちます.
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