北太平洋の底水の温暖化
Masao Fukasawa1, Howard Freeland, Ron Perkin
1Ocean Observation and Research Department, Japan Marine Science and Technology Centre, Yokosuka, 237-0061, Japan. fksw@jamstec.go.jp
Nature
|February 27, 2004
まとめ
北太平洋の最も深い海の水域は著しく温暖化しており,隔離された水質でも検出可能な変化を示しています. この発見は,海洋循環と気候変動を理解するための意味を持つ.
科学分野:
- 海洋学 海洋学 海洋学
- 気候科学 気候科学
- 地質物理学 地質物理学とは地質物理学です.
背景:
- 深海の海水における変化を観測することは,信号の大きさが小さいため,困難です.
- 深水の性質の時間的な変化は,海洋輸送と熱ハリン循環を理解するために不可欠です.
研究 の 目的:
- 1985年と1999年の深海北太平洋海洋学データを比較する.
- 北太平洋盆地における深海水の性質の変化を検知・分析する.
主な方法:
- 1985年に実施された太平洋横断海洋調査のデータを活用した.
- これらの過去のデータと1999年の再調査を比較した.
- 深水の質量の温度と性質の変化を分析した.
主要な成果:
- 北太平洋の最も深い海域で顕著な温暖化が検出された.
- 海洋盆地の全幅で観測された温暖化.
- 深水の性質の変化は,孤立した水域でも測定できるようになった.
結論:
- 北太平洋では深海の温暖化が発生しており,保温に関する以前の仮定に異議を唱えている.
- これらの発見は,以前は大気の影響から隔離されていると考えられていた水質に対する検出可能な影響を示唆しています.
- 観測された変化は,海洋水輸送と地球規模の熱ハリン循環パターンに新たな制約を与える.
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