ニュージーランドのホロセンの高頻度の氷河の変動は,北部のシグネチャーと異なる
Joerg M Schaefer1, George H Denton, Michael Kaplan
1Geochemistry, Lamont-Doherty Earth Observatory (LDEO), Palisades, NY 10964, USA. schaefer@ldeo.columbia.edu
まとめ
ニュージーランドにおけるホロセンの氷河の変動.
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
- 気候科学 気候科学
背景:
- ホロセーン期の半球間気候変化のタイミングと原因はよくわかっていない.
- 過去の気候ダイナミクスを再構築するには,高解像度の古気候記録が必要です.
研究 の 目的:
- ニュージーランドの南アルプスのホロセンの氷河の変動を調査するために.
- これらの出来事の高解像度の時系列を確立するために.
- これらの気候変動の原動力を理解するために.
主な方法:
- 高解像度ベリリウム-10 (10Be) 年代表.
- 過去7000年の氷河の変動を分析した.
- 北半球の気候パターンとの比較.
主要な成果:
- 過去千年に少なくとも5つの氷河の進出イベントが起こった.
- 氷河の広さは,ホロセンの半ばから後半まで減少した.
- ニュージーランドの氷河の進歩は北半球の暖かい時期と一致しました.
結論:
- ニュージーランドのホロセンの氷河の動態は,北半球のパターンと対照的です.
- 地域的なメカニズムは,ニュージーランドの気候に影響を与えた可能性が高い.
- 太平洋南西部の大気循環の変化がこれらの変動を誘発したのかもしれない.
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