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白天和夜晚的云层不对称, 阻止了金星的早期海洋,
Martin Turbet1, Emeline Bolmont2, Guillaume Chaverot2
1Observatoire astronomique de l'Université de Genève, Versoix, Switzerland. martin.turbet@unige.ch.
Nature
|October 14, 2021
概括
早期的金星可能从来没有表面海洋, 地球
科学领域:
- 星球科学
- 气候模型
- 天体生物学
背景情况:
- 地球已经有了近40亿年的海洋, 而火星显示了过去表面水的证据.
- 金星目前完全干燥,其早期历史被全球复苏事件所掩盖.
- 之前关于行星水凝结的研究使用了有限的单维气候模型.
研究的目的:
- 在早期的金星和地球上研究水凝结的条件.
- 了解大气循环和云在地球气候稳定中的作用.
- 为了确定金星表面是否有海洋.
主要方法:
- 使用了早期金星和地球的三维全球气候模型模拟.
- 分析了水云的影响,特别是它们的夜间形成和变暖效应.
- 在不同阳光照射水平下的模拟气候条件.
主要成果:
- 在早期的金星上,水云产生了净变暖效应,抑制了表面水的凝结.
- 即使在温和的阳光照射水平 (地球太阳恒定的0.95倍),金星也无法维持表面的水.
- 地球的海洋可能是由于微弱的年轻太阳而在明显较低的阳光条件下形成的.
结论:
- 由于水不能在金星表面凝结而形成海洋.
- 地球的海洋形成是由于早期太阳的衰弱而形成的.
- 一个"蒸汽地球"状态,所有的水蒸发,是当今地球的一个潜在的替代稳定状态.
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