初期の地球が二酸化炭素の雲によって引き起こされた不可逆的な氷河化への感受性
1Department of Geosciences, The Pennsylvania State University, University Park 16802, USA.
Nature
|September 17, 1992
まとめ
初期の地球の気候モデルは,太陽光発電量が減少すると,脱走氷河が起こりうることを示唆しています. しかし,シミュレーションでは,初期の地球は,強い温室効果により,不可逆的な凍結を防ぐために,居住可能であり続けていた可能性があることが示されています.
科学分野:
- 気候科学 気候科学
- 惑星科学 惑星科学
- 地質物理学 地質物理学とは地質物理学です.
背景:
- シンプルなエネルギーバランス気候モデルでは,太陽光発電量がわずかに減少した脱走氷河を予測しています.
- 初期の地球は,太陽の光度が著しく低い (25-30%未満) 経験しました.
- 高濃度の大気中の二酸化炭素 (CO2) は,初期の地球温暖化を維持するための好意的な説明である.
研究 の 目的:
- 太陽の明るさが低いにもかかわらず,初期の地球での気候の安定性を調査するために.
- 海洋の急速な凍結による不可逆的な氷河化のリスクを評価する.
- 初期の地球の気候動態におけるCO2雲の役割を調査する.
主な方法:
- ブディコ/セラーズ型のエネルギーバランス気候モデルを使用した.
- 低太陽光輝度を含む初期の地球の条件のシミュレーションを組み込みました.
- 高反射性CO2雲の潜在的形成をモデル化した.
主要な成果:
- 海洋は大気中のCO2が蓄積するよりもはるかに早く凍結し,気候の安定性を脅かします.
- 初期の地球の過去における一時的な地球規模の氷河化は,二酸化炭素の雲による不可逆的であったかもしれない.
- シミュレーションによると,これらのCO2雲は,火星の初期に観測された雲に似ています.
結論:
- 反射する二酸化炭素雲の形成は,初期の地球に不可逆的な氷河化をもたらした可能性がある.
- 初期の地球の歴史において一貫して温暖な気候は,現在の居住可能性にとって極めて重要でした.
- 初期の気候の動態を理解することは,時間の経過とともに惑星の居住性を理解するための鍵です.
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