最後の氷河期間の南極の気候変化の局所軌道強制
1Department of Oceanography, Texas A&M University, College Station, TX 77843, USA.
Science (New York, N.Y.)
|May 13, 1998
まとめ
南極の気候の変化は,最後の氷河期間の北半球の変化に先立ちました. 海氷と海のモデルでは,局所的なプレセッション・フォッシングと海氷の反応が,半球の気候動態を理解するために極めて重要なこの相相オフを説明することを確認しました.
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
- 気候モデリング
- 海洋学 海洋学とは
背景:
- 最後の氷河間期は,半球間の非同期的な気候変化を示した.
- この間隔の間,南極の気候の変動は北半球のそれより先行した.
- 半球間気象相相相相補の理解は,過去の気候の動態を再構築するための鍵です.
研究 の 目的:
- 南極の気候変動を誘発するプレセッションフォースの役割を調査する.
- 海氷被覆の補正が半球間気候相遅れを説明するという仮説を検証する.
- 最後の氷河期間の気候動態を,カップリングされた海氷-海洋モデルを使用して分析する.
主な方法:
- 結合された海氷・海洋一般循環モデルを利用した.
- 最後の氷河期間の3つの異なる間隔のシミュレーションされた気候条件.
- 南極の海氷の範囲と気候に局所的なプレセーションフォッシングの影響を評価した.
主要な成果:
- モデルシミュレーションは,プレセッションフォースを南極の気候変化と結びつける仮説を裏付けました.
- 重要なメカニズムとして,海氷の覆いに対する修正反応が特定されました.
- このモデルは,南極の気候変動の観測された段階のリードを成功裏に再現した.
結論:
- 海氷の反応によって媒介されるプレセッション・フォッシングの局所的な変化は,南極の気候が北半球の変化を導いていることを説明できる.
- このメカニズムは,半球間気候の動態における相相オフセットを理解するために極めて重要です.
- この発見は,異なる地質的時間尺度における過去の気候変動の解釈に意味を持つ.
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