エルニーニョ/南方振動と,過去千年における熱帯太平洋の気候
Kim M Cobb1, Christopher D Charles, Hai Cheng
1Scripps Institution of Oceanography, University of California-San Diego, La Jolla, California 92093, USA. kcobb@gps.caltech.edu
Nature
|July 18, 2003
まとめ
過去のエルニーニョ/南方振動 (ENSO) の変動性を理解することは,気候変動の評価に不可欠です. サンゴの記録は,ENSOの活動が17世紀半ばにピークを迎えたことを明らかにし,内部システムのダイナミクスがその変化の多くを駆動することを示唆しています.
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:
- 将来の気候変動の評価は,自然の気候変動の変動性を理解することに依存しています.
- エルニーニョ/南部振動 (ENSO) は,熱帯太平洋の気候変動の主要な要因である.
研究 の 目的:
- 過去1,100年の熱帯太平洋の気候変動を再構築する.
- エルニーニョ/南方振動 (ENSO) の行動とその平均気候条件との関係を分析する.
主な方法:
- パルミラ島からの化石・サンゴの酸素同位体記録を組み合わせる.
- 熱帯太平洋の気候変動の30年から150年の窓を分析する.
主要な成果:
- 中部熱帯太平洋の気候は,冷たい/乾燥 (10世紀) から暖かい/湿った (20世紀) に変化した.
- ENSOの行動の幅広い範囲が観察され,平均気候と相関が薄い.
- ENSOの最も活発な活動は,17世紀半ばに発生した.
結論:
- 過去1千年におけるエルニーニョ/南方振動 (ENSO) 変動の大部分は,ENSOの内部システム動力学から生じる可能性がある.
- サンゴの同位体記録は,過去の気候の変動性とENSOの行動に関する貴重な洞察を提供します.
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