初期のプレイストセンの氷河周期と,統合された夏の太陽照射を強制する
1Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA. phuybers@fas.harvard.edu
まとめ
氷河周期は,地球の傾きによって制御されるが,プレセーションによって制御されない. これは,氷河が夏の太陽光総量に反応するのであり,夏の長さが影響するのであり,その強さが影響するだけではないからです.
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
- 地球科学 地球科学 地球科学
- 気候のダイナミクス
背景:
- 北半球の夏の太陽照射の長期的変動は,伝統的に氷河期と関連しています.
- 初期のプレイストセンの氷河周期は4万年周期を示しており,これはプレセッショナル・インソレーションの2万年周期と対照的です.
研究 の 目的:
- 観測された氷河周期と太陽照射強制の間の不一致を解決するために.
- プレイストセンの初期の氷河期におけるプレセシオン (20,000年サイクル) よりも傾斜 (40,000年サイクル) の優位性を説明する.
主な方法:
- 長期にわたる太陽照射変動の分析.
- 氷河周期周期と天文周期の比較 (斜率と前退).
- ケプラーの第二法則の適用は,季節の期間を理解するために.
主要な成果:
- 初期のプレイストセンの氷河周期は,地球の傾斜周期と一致するが,プレセシオン周期ではない.
- 氷河は,ピークの強度だけでなく,夏の太陽光に敏感です.
- 地球の軌道距離の影響を受ける夏の期間は,総日照の重要な要因です.
結論:
- 地球の傾きは,夏の期間をコントロールしているため,プレイストセンの初期の氷河化の主要な原動力です.
- 氷河が集積された太陽光への感受性は,古気候学における4万年の問題を解決している.
- ケプラーの第二法則は,季節の期間に影響を及ぼす傾斜が,氷河期におけるプレセッションよりも影響力がある理由を説明しています.
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