北大西洋の8世紀の大気変動
1Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL 33149, USA. National Oceanic and Atmospheric Administration Paleoclimatology Program and the Institute for Arctic and Alpine Research, University of Colorado, B.
Science (New York, N.Y.)
|November 27, 1999
まとめ
825年にわたる熱帯大西洋の気候の変動は,重要な10年モードを明らかにします. 世紀規模の変化と700年ほど前の北半球の気候変化の可能性も明らかである.
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-大気圏のダイナミクス
- トロピカル気象学 トロピカル気象学
背景:
- 熱帯北大西洋の気候は,貿易風,熱帯間の収束地帯 (ITCZ),および海面温度によって影響を受けます.
- 過去の気候の変動を理解することは,将来の気候の動向を予測する上で極めて重要です.
研究 の 目的:
- カリブ海の高解像度堆積物データを用いて,過去825年の熱帯上流と貿易風の変動を復元する.
- 熱帯大西洋の気候変動の支配的なモードを調査する.
主な方法:
- カリブ海からの高解像度堆積物核の分析.
- サブデケダルのスケールの古気候再構築.
主要な成果:
- 大西洋変動の顕著な10年 (12-13年) のモードが確認され,おそらく海洋-大気結合によって引き起こされた.
- 証拠は,熱帯大西洋の世紀規模の変動が大きいことを示唆しています.
- この地域の特徴として,異なった10年間の変動様式は特定されなかった.
結論:
- 熱帯大西洋は,重要な10年および世紀規模の気候変動の変動を示しています.
- この地域は,およそ700年前に北半球の大規模な気候変化の影響を受けた可能性がある.
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