火星の南極のアルベドは,大気動態の地形的な強制によって決定される
Anthony Colaprete1, Jeffrey R Barnes, Robert M Haberle
1NASA Ames Research Center, Space Science Division, Moffett Field, Mountain View, California 94035, USA. Anthony.Colaprete-1@nasa.gov
Nature
|May 13, 2005
まとめ
火星の南極帽には,衝突盆地によって引き起こされる2つの異なる地域気候があります. これらの気候は,凍結堆積に影響を与え,スラップの氷と非対称な後退のようなキャップの謎の特徴を説明します.
科学分野:
- 惑星科学は惑星科学である.
- 気候モデリング
- 火星の地質物理学について
背景:
- 火星の南極帽の恒久的な二酸化炭素の氷,クリプティック領域のスラブ氷,そして非対称的な後退は説明がつかないままです.
- 以前の研究では,火星の南極点のこれらの謎めいた特徴について,包括的な説明がありませんでした.
研究 の 目的:
- 火星の南極の独特の地域気候を調査するために.
- これらの気候に影響を与えるダイナミックな強制メカニズムを理解するために.
- 観測された表面の凍結堆積のスタイルとキャップのアルベドを説明するために.
主な方法:
- 火星の南極点の観測を宇宙船で利用した.
- 地域気候の動態をシミュレートするために気候モデリングを使用しました.
- 表面の凍結堆積パターンと気候との関係を分析した.
主要な成果:
- 火星の南極で2つの異なる地域気候が特定され,ArgyreとHellasの衝撃盆地によって駆動されています.
- 地域的な気候が表面の凍結堆積のスタイルを制御することを示した.
- 降水が冷たい,嵐の多い地域でのの蓄積を支配し,直接の蒸気堆積がより暖かく,より澄んだ地域を支配することを示した.
結論:
- 非対称的な後退とクリプティック地域のような特徴は,2つの異なる地域気候によって説明されます.
- 大規模衝突盆地によるダイナミックフォッシングは,これらの地域的な気候の違いの主な原動力である.
- 氷の沈殿様式 (降水と蒸気沈殿) の違いが南極帽のアルベドを決定する.
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