最後の氷河期と氷河期間の移行期における南米熱帯の初期の温暖化
G O Seltzer1, D T Rodbell, P A Baker
1Department of Earth Sciences, Syracuse University, 204 Heroy Geology Laboratory, Syracuse, NY 13244, USA. goseltze@syr.edu
まとめ
熱帯アンデス地方の氷河は2万2000万19,500年前に後退し,北半球の大幅な温暖化を示しています. 温度によって引き起こされるこの脱氷は,北米とヨーロッパの温暖化現象が起こる前に起こった.
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
- 氷河学 氷河学とは
- アンデス山脈の気候史 アンデス山脈の気候史
背景:
- 熱帯アンデス氷河は,過去の気温変化の重要な代理です.
- 脱氷のタイミングを理解することは,気候の再構築に不可欠です.
研究 の 目的:
- 熱帯アンデスにおける脱氷のタイミングを決定する.
- 熱帯アンデス山脈の脱氷と北半球の気候現象との関係を調査する.
主な方法:
- 熱帯アンデスから採取した湖内部の堆積物分析.
- 氷河堆積物の放射性炭素年代測定. 氷河堆積物の放射性炭素年代測定. 氷河堆積物の放射性炭素年代測定.
主要な成果:
- ティティカカ湖とジュニン湖の脱氷は,現在から2万2000年から1万9500カレンダー年前の間に起こった.
- この脱氷は,ボリング・アレルード温暖化と北米の脱氷より数千年前まで遡ります.
- 熱帯アンデスでは,継続的に湿った条件下で脱氷を経験しました.
結論:
- 年間平均気温は,熱帯アンデスにおける氷河形成の主な要因である.
- 熱帯アンデスの脱氷は北半球の温暖化に先行し,複雑な半球間気候動態を示唆しています.
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