大西洋北東部の波の気候の変化に関する微小地震学的証拠
I Grevemeyer1, R Herber, H H Essen
1Department of Earth Sciences, University of Bremen, Germany. ingo@geophys2.uni-bremen.de
Nature
|December 1, 2000
まとめ
気候変動により,海波の高さが上昇している可能性があります. 海洋波に関連した微小地震,地面の振動に関する40年間の研究は,過去20年間で北東大西洋の波の活動が倍増したことを明らかにしています.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 海洋学 海洋学とは
- 気候科学 気候科学
背景:
- 海面上昇と波長の上昇は,沿岸地域と海洋産業に脅威をもたらしています.
- 長期的な気候変動の検出は,観測データの矛盾によって妨げられています.
- 4〜16秒周期の微小地震,地震の振動は,海波の活動と相関しています.
研究 の 目的:
- 北東大西洋の波の気候を再構成する.
- 過去40年間の波の高さの潜在的な傾向を調査するために.
- マイクロ地震データと気候変動指標の関連性を評価する.
主な方法:
- ハンブルク,ドイツから冬の微小地震の40年間の連続記録を利用した.
- 強い地震活動の期間を特定するために微小地震データを分析しました.
- 小規模地震の傾向は,気温と嵐の強さを含む歴史的な気候データと相関しています.
主要な成果:
- 1954年から1977年にかけて,月平均7日強烈な微小地震活動が検出され,有意な傾向は見られませんでした.
- 記録の後半に強い微小地震活動の有意な増加が観察され,月に約14日に達しました.
- 再構築された波の気候は,過去20年間で北東大西洋における波の活動が2倍になったことを示している.
結論:
- この研究は,過去20年間に北東大西洋の波の高さが著しく増加した証拠を提供する.
- この波動の増加は,地表気温上昇と地域の嵐の増加に並行しています.
- この発見は,波長の上昇と地域温暖化の両方を引き起こしている共通の気候強制メカニズムを示唆しています.
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