火星の氷河の形成は,高傾度での大気降水によるものです
F Forget1, R M Haberle, F Montmessin
1Laboratoire de Météorologie Dynamique, Institut Pierre Simon Laplace, Université Paris 6 Boite Postale 99, 75252 Paris cedex 05, France. forget@lmd.jussieu.fr
まとめ
火星 火星 火星 火星
科学分野:
- 惑星科学 惑星科学
- 気候モデリング
- 地質学 地質学 地質学
背景:
- 火星は,冷たく乾燥した表面状態で,主に極地で水氷があります.
- 地質学的に最近の氷河のような地形は,火星の熱帯と中緯度で観察されています.
- この氷の起源は議論されており,地下貯水池や大気源が提案されている.
研究 の 目的:
- 過去の気候条件をシミュレーションすることによって,火星の氷河の起源を調査する.
- 異なる傾斜下での大気氷の蓄積の仮説を検証するために.
- 観測された氷河の地形位置とモデル予測を相関させるため.
主な方法:
- 現在の火星の水循環の高解像度の気候シミュレーション.
- モデルは45度の傾斜に調整され,数百万年前の条件をシミュレートしています.
- シミュレートされた氷の蓄積地帯と,氷河の既知の地形サイトを比較する.
主要な成果:
- 気候モデルは,特定の地域における氷の蓄積を予測した.
- 予測された氷の蓄積地帯は,観測された氷河の地形位置と一致しています.
- 主な蓄積地域には,大きな火山の西側の側面と東ヘラス地域が含まれています.
結論:
- この研究は,火星の氷河氷の大気起源を支持している.
- シミュレーションにより,過去の傾斜下での降水が火星の氷河を形成する可能性があることが示されています.
- この研究は,気候モデルと火星の氷河の地質学的証拠を調和させています.
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