ヤング・ドライアス時代の氷河の広がりと,北極カナダのバフィン島での8.2kaのイベント
Nicolás E Young1, Jason P Briner, Dylan H Rood
1Department of Geology, University at Buffalo, 411 Cooke Hall, Buffalo, NY 14260, USA. nicolasy@ldeo.columbia.edu
Science (New York, N.Y.)
|September 18, 2012
まとめ
この8.2kaの寒冷現象は,カナダ北極のバフィン島で氷河が大きく前進し,山の氷河はヤング・ドライアスの大きさを上回った. これは,若いドライアスと比較して異なる季節的な冷却パターンを示唆しています.
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
- 氷河学 氷河学とは
- 四次科学とは四次科学である.
背景:
- グリーンランドの氷芯は,ヤング・ドライアス (YD) と8.2kaの寒冷イベントが現在より著しく寒かったことを示しています.
- 過去の気候変動に対する氷床と氷河の反応を理解することは,将来の氷床の感受性を予測するために不可欠です.
研究 の 目的:
- ローレンティード氷床とバフィン島の山の氷河が8.2kaの気候イベントにどのように反応したかを再構築する.
- 8.2 ka イベント中の氷河の振る舞いを,若いドライアスのものと比較するために.
主な方法:
- パレオ気候データのための氷芯の分析.
- バフィン島で氷床の出口氷河と山の氷河を復元する.
主要な成果:
- ローレンティード氷床の出口氷河とバフィン島の山の氷河の大規模な前進は,8.2kaのイベントに反応して起こった.
- 8.2 ka イベント中の山の氷河は,若いドリアス期の氷河よりも大きかった.
- 8.2 ka イベント中の冷却は,冬のバイアスの冷却よりも季節的に均一であった可能性が高いです.
結論:
- 8.2 ka イベントは,氷河の大幅な膨張を引き起こし,気候の混乱に対する氷床と氷河の有意な感受性を示しました.
- 観測された氷河の動態と季節的な気温分布は,ホロセンの初期における地域的な気候の変動に関する洞察を提供します.
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