Effects of Local Dust Storms on the Upper Atmosphere of Mars: Observations and Simulations
Effects of Local Dust Storms on the Upper Atmosphere of Mars: Observations and Simulations
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DOI：
10.1029/2018je005864
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发表时间：
2019-02
期刊：
影响因子：
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通讯作者：
J. Qin;H. Zou;Y. Ye;Z. Yin;Jing Song Wang;E. Nielsen
中科院分区：
文献类型：
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作者：
J. Qin;H. Zou;Y. Ye;Z. Yin;Jing Song Wang;E. Nielsen
通过MGS（火星全球探测者）射电掩星实验对火星上层大气和下层大气的观测，研究了局部沙尘暴对火星上层大气的影响。在火星年（MY） 27 l135 - 150°期间，北半球高纬度地区的电离层剖面被认为受到低纬度地区局部沙尘暴的影响。提出了一种利用电离层主峰高度估算火星上中性密度的方法。通过该方法，计算了沙尘暴期间该地区130公里大气中性密度（或CO2密度）。MCD V4.3（火星气候数据库，版本4.3）用于导出同一地区和时期的正常（或无沙尘暴）中性密度。通过分析计算密度与MCD （V4.3）模拟密度的差异，可以定量推导局地沙尘暴对高层大气密度的影响。基于高层大气密度的变化，利用光化学平衡模式可以模拟沙尘暴下区域电离层主峰的行为。将模拟的电离层参数与MGS观测的电离层参数进行了比较，发现两组剖面数据相互吻合，从而表明所采用的方法估计上中性密度是准确的。
The effects of a local dust storm on the upper atmosphere of Mars are researched through the observations of the lower and upper Martian atmosphere in the MGS (Mars Global Surveyor) radio occultation experiments. The ionosphere profiles in the high‐latitude region of northern hemisphere are thought to be under the influence of a local dust storm occurring in the low‐latitude areas during Ls 135–150°, Mars Year (MY) 27. A method to estimate the Martian upper neutral densities via the heights of ionospheric main peak is presented. Through the method, the 130‐km atmospheric neutral densities (or CO2 densities) of the area during the dust storm were calculated. MCD V4.3 (Mars Climate Database, Version 4.3) is used to derive the normal (or dust‐storm‐free) neutral densities of the same region and period. By analyzing the differences between the calculated densities and MCD (V4.3) simulated ones, the influence of the local dust storm on the upper atmosphere densities can be quantitatively derived. Based on the variation of the upper atmosphere densities, the behavior of regional ionospheric main peak under the dust storm can be simulated by a photochemical equilibrium model. The simulated ionosphere parameters are compared with the MGS‐observed ones, and it is found that two profile data sets are consistent with one another, thus indicating that the method employed to estimate the upper neutral densities is accurate.