氷河期におけるエルニーニョのようなパターン 熱帯太平洋海面温度 海面温度
Athanasios Koutavas1, Jean Lynch-Stieglitz, Thomas M Marchitto
1Lamont-Doherty Earth Observatory and Department of Earth and Environmental Sciences, Columbia University, Palisades, NY 10964, USA. athan@ldeo.columbia.edu
まとめ
太平洋の海面温度は3万年以上にわたり,世界の気候に影響を及ぼした. これらの温度の変化は,特に最後の氷河期最大期の間,大気パターンと海洋条件の変化を明らかにします.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 海洋学 海洋学 海洋学
- 気候科学 気候科学
背景:
- 東赤道太平洋の冷たい舌の海面温度 (SST) は,地球全体の大気循環に大きな影響を与える.
- この地域の過去の気候の変動を理解することは,将来の気候の動態を予測するために不可欠です.
研究 の 目的:
- 最後の氷河期最大 (LGM) から現在まで,東赤道太平洋の冷たい舌の気候の変動を再構築し,分析する.
- SSTの変動と地球規模の大気循環パターンとの関係を調査する.
主な方法:
- ガラパゴス諸島の近くの海底堆積物からフォラミニフェラのマグネシウム/カルシウム比を用いたSST記録の再構築.
- 過去3万年にわたる気候変動の分析,SSTデータとプレセーション誘発の季節性との相関.
主要な成果:
- 冷たい舌のSSTは,過去3万年にわたって,プレセーションによって引き起こされた季節性との一貫した変動を示した.
- ラスト・グラシアル・マキシマムの冷却 (1.2°C) は,熱帯の気温グラデーションの緩和,大気循環の弱まり (ハドリーとウォーカー),熱帯間の収束地帯の南向きのシフト,エルニーニョのようなパターンを示した.
- 中 Holocene の冷却は,強化された SST グラデーションと強化された貿易風のラニーニャのようなパターンを示唆しました.
結論:
- 熱帯太平洋のSSTグラデーションは,世界の気候の変動に重要な役割を果たしています.
- 過去の気候再構築は,熱帯太平洋のSSTの変化に対する大気循環の感受性についての洞察を提供します.
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