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Updated: Jun 24, 2026

08:03
Study of Protein Dynamics via Neutron Spin Echo Spectroscopy
Published on: April 13, 2022
氷河期間の氷河期間のサイクルを通してエルニーニョ-南方振動の変動
A W Tudhope1, C P Chilcott, M T McCulloch
1Department of Geology & Geophysics, Edinburgh University, Edinburgh, EH9 3JW, UK. mail: sandy.tudhope@ed.ac.uk
まとめ
エルニーニョ・サザン・オシレーション (ENSO) は,氷河期にも拘らず,13万年間続いている. しかし,20世紀におけるENSOの活動は,以前の暖かい時期と冷たい時期よりも強かった.
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
- 気候科学 気候科学
- 海洋学 海洋学とは
背景:
- エルニーニョ・サザン・オシレーション (ENSO) は,世界の年間間の気候変動の主な原動力である.
- ENSOの気候変動に対する感受性を理解することは,温室効果温暖化への影響の不確実性のために非常に重要です.
- 過去のENSOの行動は,変動する気候条件への反応の洞察を提供します.
研究 の 目的:
- 過去13万年にわたるENSOの歴史的行動と変動を調査する.
- ENSOが過去の氷河期および氷河間期に稼働していたかどうかを判断する.
- 20世紀におけるENSOの強さを,それ以前の気候状態におけるその行動と比較する.
主な方法:
- パプアニューギニアの毎年帯状のサンゴの骨格の分析.
- 珊瑚の記録から地化学的なプロキシを用いて,過去のENSO活動の再構築.
- 異なる古気候条件 (氷河期,氷河間,20世紀) におけるENSO振幅の比較.
主要な成果:
- 証拠によると,ENSOは少なくとも13万年前から存在しており,低温と変化した太陽力による氷河期を含む.
- 20世紀におけるENSOの活動は,以前の氷河期および氷河間期におけるその幅と比較して著しく強かった.
- ENSOの振幅は,冷たい氷河期に鈍化し,プレセッショナル軌道変動の影響を受けたようです.
結論:
- ENSOは,過去の大規模な気候変動に対する耐性のある,長年の気候現象である.
- 20世紀は,ENSOの長い歴史に比べて,ENSOの活動が強化された時期を経験しました.
- ENSOの振幅の変化は,氷河期気候状態と軌道強制との相互作用に関連している可能性があります.
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