Can we constrain the origin of Mars' recurring slope lineae using atmospheric observations?
Can we constrain the origin of Mars' recurring slope lineae using atmospheric observations?
复制标题
我们可以利用大气观测来限制火星重复斜坡线的起源吗？
DOI：
10.1016/j.icarus.2021.114688
复制
发表时间：
2022
期刊：
影响因子：
3.2
通讯作者：
Nakagawa Hiromu
中科院分区：
文献类型：
--
作者：
Kurokawa Hiroyuki;Kuroda Takeshi;Aoki Shohei;Nakagawa Hiromu
流动的水和盐水被认为是在火星陡峭的温暖斜坡上季节性重现的黑色条纹，称为重现性斜坡线（RSL），沿着其他不涉及水的形成机制。这项研究的目的是检查是否从RSL的水蒸气蒸发，无论是从淡水或盐水，是通过观察水蒸气和/或云检测。在这项研究中，我们总结了可能的速率和持续时间的水汽排放从RSL在不同的情况下，模拟如何排放的水汽在全球气候模式中的行为，并讨论在现有的和未来的探索在最低点观测水汽的可探测性。我们发现，在典型的情况下，快速的水平消散在行星边界层（PBL）的水蒸气释放后，禁止云的形成和多余的水蒸气与现有的观测背景区分。因此，我们得出结论，RSL活动和上覆水汽柱密度之间缺乏相关性并不一定排除RSL的湿起源。尽管如此，我们也发现，水蒸气往往积累在盆地和山谷中，在某些情况下，由于地形和低PBL的综合影响，我们建议这样的配置的位置作为目标，为未来的火星大气研究，致力于量化水蒸气释放（与RSL），以阐明RSL的形成机制（S）在地球上。
Flowing water and brine have been proposed to cause seasonally reappearing dark streaks called recurring slope lineae (RSL) on steep warm slopes on Mars, along with other formation mechanisms that do not involve water. This study aims to examine whether the evaporation of water vapor from the RSL, whether from fresh water or brine, is detectable by observing water vapor and/or clouds. In this study, we summarize the possible rate and duration of water-vapor emission from RSL in different scenarios, simulate how the emitted water vapor behaves in a global climate model, and discuss the detectability of water vapor in nadir observations during existing and future explorations. We found that, in typical cases, rapid horizontal dissipation within the planetary boundary layer (PBL) following the release of water vapor prohibits cloud formation and the excess water vapor from being distinguished from the background with existing observations. Thus, we conclude that the lack of correlation between the RSL activities and the overlying water-vapor column density does not necessarily rule out the wet origin of RSL. Nevertheless, we also found that water vapor tends to accumulate in basins and valleys in some cases due to the combined effects of topography and low PBL; we suggest the locations of such configuration as targets for future atmospheric studies of Mars dedicated to quantifying water-vapor release (associated with RSL) to elucidate the formation mechanism(s) of the RSL on the planet.