Precipitation Climatology on Titan-like Exomoons
Precipitation Climatology on Titan-like Exomoons
复制标题
类泰坦系外卫星的降水气候学
DOI：
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发表时间：
2015
影响因子：
2
通讯作者：
T. Tokano
中科院分区：
文献类型：
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作者：
T. Tokano
地球大陆表面液态水的可用性部分依赖于水的降水。这意味着系外卫星的可居住性不仅要考虑液态水存在的表面温度和大气压力，还要考虑全球降水气候学。本研究利用全球气候模型探讨了类泰坦系外卫星的降水气候学对这些卫星轨道配置的敏感性。降水率主要取决于纬度，对行星的倾角和月球的自转速度很敏感。在缓慢旋转的卫星上，随着倾角的增加，降水向高纬度移动，而在快速旋转的卫星上，纬度分布不强烈地依赖于倾角。如果行星的倾角和月球的轨道距离很小，那么星蚀会导致亚行星和反行星之间的平均表面温度和表面压力的纵向变化。在这种特殊情况下，反行星面通常比亚行星面接收到更多的降水。然而，与潮汐锁定的系外行星相比，具有致密大气的系外卫星上的降水通常发生在任何经度。
The availability of liquid water on the surface on Earth’s continents in part relies on the precipitation of water. This implies that the habitability of exomoons has to consider not only the surface temperature and atmospheric pressure for the presence of liquid water, but also the global precipitation climatology. This study explores the sensitivity of the precipitation climatology of Titan-like exomoons to these moons’ orbital configuration using a global climate model. The precipitation rate primarily depends on latitude and is sensitive to the planet’s obliquity and the moon’s rotation rate. On slowly rotating moons the precipitation shifts to higher latitudes as obliquity is increased, whereas on quickly rotating moons the latitudinal distribution does not strongly depend on obliquity. Stellar eclipse can cause a longitudinal variation in the mean surface temperature and surface pressure between the subplanetary and antiplanetary side if the planet’s obliquity and the moon’s orbital distance are small. In this particular condition the antiplanetary side generally receives more precipitation than the subplanetary side. However, precipitation on exomoons with dense atmospheres generally occurs at any longitude in contrast to tidally locked exoplanets.