インソレーションによって引き起こされる10万年の氷河周期と,氷床の体積のヒステレシス
Ayako Abe-Ouchi1, Fuyuki Saito, Kenji Kawamura
1Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa 277-8568, Japan. abeouchi@aori.u-tokyo.ac.jp
Nature
|August 9, 2013
まとめ
北半球の氷床は,日差しと内部フィードバックによって引き起こされる10万年のサイクルを示しています. 氷床のヒステリーゼは,日焼けに対する氷床の反応で,氷河周期の特徴である漸進的な成長と急速な後退を説明します.
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
- 気候モデリング
背景:
- 北半球の氷床は,漸進的な成長と急速な終結の10万年のサイクルを示しています.
- ミランコビッチの理論は,氷河周期と軌道周期を結びつけているが,太陽の照射だけでは10万年の周期性を説明できない.
研究 の 目的:
- 氷河周期の10万年周期の背後にあるメカニズムを調査する.
- 氷床の動態における内部フィードバックの役割を説明する.
主な方法:
- 総合的な気候と氷床モデルを使用した.
- 夏の日焼けに対する氷床のヒステレス反応を分析した.
主要な成果:
- 温暖化と気候,氷床,そして石層-アステノスフィアのフィードバックが合わさって,この10万年のサイクルを説明します.
- 氷床の平衡状態はヒステリーシスを示し,氷河周期周期に影響を与えます.
- 遅延した同静止反発は,氷床の急速な後退に貢献します.
結論:
- 10万年の氷河周期は,日焼けと内部フィードバックの組み合わせによって引き起こされます.
- 氷床の挙動におけるヒステリーゼは,氷河の終結を理解するために極めて重要です.
- CO2は重要な役割を果たしますが,これらの長期サイクルの主な原動力ではありません.
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