Gravity Waves in Different Atmospheric Layers During Martian Dust Storms
Gravity Waves in Different Atmospheric Layers During Martian Dust Storms
复制标题
DOI：
10.1029/2021je007170
复制
发表时间：
2022-04
期刊：
影响因子：
--
通讯作者：
Zhaopeng Wu;Jing Li;Tao Li;J. Cui
中科院分区：
文献类型：
--
作者：
Zhaopeng Wu;Jing Li;Tao Li;J. Cui
重力波普遍存在于火星大气中，对整个大气系统的耦合至关重要。最近的观测显示，在全球沙尘暴条件下，热层GW活动显著增强，这可能会增加氢的逃逸。然而，这些高海拔GW的来源及其与低层大气的联系仍不清楚。基于火星气候探测仪的多年观测，我们研究了火星大气低过渡层、中层和中上层(LP、MP和HP)三个高度范围内GW的详细分布和演化。区域沙尘暴高峰期后，热带北部地区夜间MP层GWS显著增加，势能比前或其他纬度增加4倍。这些GW与风暴期间纬向分布的分离沙尘层有很好的相关性，两者都可能是由热带急流系统产生的。除火星第28年全球沙尘暴外，全球沙尘暴期间观测到的高层大气GW主要激发在主沙尘层以上的HP层(∼50-70公里)，而北纬MP层(∼30-50公里)的极地急流可能是激发的主要来源。
Gravity waves (GWs) are ubiquitous in the Martian atmosphere and critical for coupling the entire atmospheric system. Recent observations reveal a significant enhancement of thermospheric GW activity in global dust storm conditions, which could increase hydrogen escape. However, the source of these high‐altitude GWs and their link to the lower atmosphere are still unknown. We investigate detailed GW distributions and evolutions in three altitude ranges covering the lower, middle, and middle‐to‐upper transition layers (Lp, Mp, and Hp) of the Martian atmosphere based on multiyear observations from Mars Climate Sounder. The nighttime Mp‐layer GWs in the northern tropical region increase significantly after the peak time of regional dust storms, with potential energy 4 times larger than before or at other latitudes. These GWs correlate well with a zonally distributed detached dust layer during storm time, both of which may be generated by a tropical jet system. The upper atmospheric GWs observed during global dust storms are mainly excited in the Hp‐layer (∼50–70 km) above the main dust layer, except for Mars year 28 global dust storm, when the polar jet in the Mp‐layer (∼30–50 km) at high northern latitudes may be a major excitation source.