南半球の気候振動の34万年の百年規模の海洋記録
Katharina Pahnke1, Rainer Zahn, Henry Elderfield
1School of Earth, Ocean and Planetary Sciences, Cardiff University, Park Place, Cardiff CF10 3YE, UK. pahnkek@cf.ac.uk
Science (New York, N.Y.)
|August 16, 2003
まとめ
古代海洋学記録は,南緯度の中央部が温暖な期間の南極の気候を密接に追跡することを明らかにしますが,氷河期間の明確な変動を示し,循環パターンの変化を示唆しています.
科学分野:
- パレオセアノグラフィーとは
- 気候科学 気候科学
- 南半球の気候動態 南半球の気候動態
背景:
- 南中緯度の急速な気候変化を理解することは,世界の気候モデルにとって極めて重要です.
- 以前の研究は,多くの場合,限られた古気候のプロキシに依存しており,より詳細な記録が必要である.
研究 の 目的:
- 太平洋南西部の百年規模の古海洋学記録を開発する.
- 気候関連分析のために,南極の氷核記録との詳細な比較を可能にするために.
- 南部の高緯度と中緯度間の気候の結合と分離を調査する.
主な方法:
- 太平洋南西部の百年規模の古海洋学記録の開発.
- 既存の南極とグリーンランドの氷芯記録との比較分析.
主要な成果:
- 古代海洋学記録は,氷河解凍期と氷河間期の間に南極の気候と密接な結びつきを示しています.
- 氷河断層は,南極の氷芯と比較して,より高い変動性を示しており,気候の分離を示しています.
- グリーンランドの氷芯との構造的および時間的な類似性は,氷河期間の半球間気候の同期性を示唆しています.
結論:
- 中南緯度の気候は,氷河期間の氷河期と脱氷期の間,南極の気候と密接に結びついています.
- 氷河期における南極周回循環の強化は,南部の中高緯度と高緯度間の気候の分離につながります.
- 証拠は,半球間気候の同期性を示唆し,既存の二極の気候モデルに挑戦しています.
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