The response of Martian photoelectron boundary to the 2018 global dust storm  

作　　者：Yuqi WANG Jun CUI Yong WEI Zhaopeng WU Kai FAN Zhaojin RONG Fei HE Yutian CAO Jiawei GAO 

机构地区：[1]Key Laboratory of Earth and Planetary Physics,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China [2]College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China [3]Planetary Environmental and Astrobiological Research Laboratory(PEARL),School of Atmospheric Sciences,Sun Yat-sen University,Zhuhai 519082,China [4]Center for Excellence in Comparative Planetology,Chinese Academy of Sciences,Hefei 230026,China

出　　处：《Science China Earth Sciences》2024年第9期2772-2782,共11页中国科学（地球科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.42241106)。

摘　　要：Extensive research efforts have revealed that the Martian dust storms can perturb the upper atmospheric condition and as a consequence,enhance plasma density and photoelectron flux in the ionosphere.However,previous observational studies of the Martian dust storm impacts have been restricted to regions below 400 km,which limits our understanding of the Martian dust storm effects in the upper ionosphere and magnetosphere.Here,based on the suprathermal electron measurements made by the Solar Wind Electron Analyzer onboard the Mars Atmosphere and Volatile Evolution,we identify with an automatic procedure the occurrences of all photoelectron boundary(PEB)crossings at solar zenith angle below 120°(with a dust-free median altitude of about 600 km).Using the dayside PEB as a proxy of the upper ionospheric and magnetospheric condition,we analyze the variations of the PEB altitude during the 2018 global dust storm(GDS)of Mars Year 34(MY34)and compare them with the period in MY33 when there was no global dust storm.We conclude that the column dust optical depth(CDOD)emerges as one of the main driving factors for PEB altitude variations during the GDS.Our analysis implies that the GDS can affect the Martian upper atmosphere and ionosphere over considerable distances and extended time scales.

关 键 词：Martian global dust storm Martian photoelectron boundary Upper ionosphere 

分 类 号：P185.3[天文地球—天文学] P425.55