Runaway greenhouse effect and habitability of planets : revisited

失控的温室效应和行星的宜居性：重新审视

• 批准号: 16540395
• 负责人: ABE Yutaka
• 金额: $ 2.24万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16540395/
• 关键词: runaway greenhouse; water vapor feedback; aqua planet; land planet; habitability; water; climatology; planetary science; 多重平衡状態; 太陽放射の増大

Most of the previous studies on the habitable zone implicitly assume an ocean-covered 'aqua' planet that has a large amount of liquid water like the present Earth. However, there is a possibility of a habitable 'land' planet that is covered by vast dry desert but has locally abundant water. The conditions for the existence of liquid water can be different for a less water land planet from that of an aqua planet, because, both the ice-albedo feedback, which causes the complete freezing, and the runaway greenhouse, which causes the complete evaporation, are caused by the phase change of water. 1. We performed experiments using a general circulation model CCSR/NIES AGCM5.4g and determined the minimum solar flux that cause the complete evaporation of water from the surface. 2. If the distribution of the ground water is completely controlled by the atmospheric circulation, the ground water is localized in high latitude area. Then, the liquid water exists on the surface beyond the critical flux of the runaway greenhouse. 3. We found multiple equilibrium states. 4. Vapor abundance in the stratosphere is kept very low while water exists on the surface. Thus, this state is very stable against the atmospheric escape. 5. Water abundance which is too large will not allow the atmospheric control of water distribution. Then, the stability of liquid water is limited by that of an aqua planet. This suggests, against the intuition, that the stable range of liquid water is wider for less water "land" planets than water abundant "aqua" planets.

先前关于宜居区的大多数研究都隐式地假设了一个覆盖的“水上”行星，该星球具有大量的液态水，如当下地球。但是，有可能居住的“土地”行星被广阔的干燥沙漠覆盖，但有局部丰富的水。对于较少的水地行星而言，液态水存在的条件与Aqua星球的条件可能不同，因为，引起完全冰冻的冰 - 艾尔底反馈，而导致完全蒸发的失控的温室都是由水的相变引起的。 1。我们使用一般循环模型CCSR/NIES AGCM5.4G进行了实验，并确定了导致水从表面完全蒸发的最小太阳通量。 2。如果地下水的分布完全由大气循环控制，则将地下水定位在高纬度地区。然后，液态水存在于失控温室的临界通量之外的表面上。 3。我们发现了多个平衡状态。 4。平流层中的蒸气丰度保持非常低，而水则存在。因此，这种状态在大气中逃脱非常稳定。 5。太大的水丰度将不允许对水分布的大气控制。然后，液态水的稳定性受到水上行星的限制。这表明，反对直觉，稳定的液态水范围比水的“陆地”行星要少于水。

项目成果

Stability of Liquid Water on a Land Planet : Liquid Water at Larger Insolation than the Runaway Greenhouse Limit.

陆地行星上液态水的稳定性：日照量大于失控温室极限的液态水。

• 发表时间: 2005
• 期刊: Proceedings of the 38th ISAS Lunar and Planetary Symposium (Kato, M. and S.Tanaka) (Japan Aerospace Exploration Agency, Sagamihara) 56-59
• 作者: Abe;Y.;Y.Uehara;A.Abe-Ouchi
• 通讯作者: A.Abe-Ouchi

Stability of Liquid Water on a Land Planet : Liquid Water at Larger Insolation than the Runaway Greenhouse Limit

陆地行星上液态水的稳定性：日照量大于失控温室极限的液态水

• 发表时间: 2006
• 期刊: Proceedings of ISAS Lunar and Planetary Symposium 38(in press)
• 作者: Abe;Y.;Y.Uehara;A.Abe-Ouchi
• 通讯作者: A.Abe-Ouchi