- K. Gui, Wenrui Yao, H. Che, Linchang An, Yu Zheng, Lei Li, Hujia Zhao, Lei Zhang, J. Zhong, Yaqiang Wang, Xiaoye Zhang. 2022. Two mega sand and dust storm events over northern China in March 2021: transport processes, historical ranking and meteorological drivers Record-breaking dust loading during two mega dust storm events over northern China in March 2021: aerosol optical/radiative. Abstract: Although a remarkable reduction in the frequency of sand and dust storms (SDSs) in the past several decades has been reported over northern China (NC), two unexpected mega SDSs occurred on March 15–20, 2021 and March 27–29, 2021 (abbreviated as the “3.15” and “3.27” SDS events), which has reawakened widespread concern. This study characterizes the origins, transport processes, magnitudes of impact, and meteorological causes of these two SDS events using a long-term 20 (2000–2021) dust optical depth (DOD) dataset retrieved from MODIS measurements and a comprehensive set of multiple satellite and ground-based observations combined with atmospheric reanalysis data. During the 3.15/3.27 event, the invasion of dust plumes greatly degraded the air quality over large areas of NC, reaching extremely hazardous levels, with the maximum daily mean PM10 concentration of 7058 μg m (2670 μg m) recorded on March 15 (28). This study characterizes the optical, microphysical, and radiative properties of aerosols and their meteorological drivers during these two SDS events using the sun 25 photometer observations in Beijing and a comprehensive set of multiple satellite (including MODIS, VIIRS, CALIOP, and Himawari-8) and ground-based observations (including the CMA visibility network and AD-Net) combined with atmospheric reanalysis data. Moreover, a long-term (2000–2021) dust optical depth (DOD) dataset retrieved from MODIS measurements was also utilized to evaluate the historical ranking of the dust loading in NC during dust events. During the 3.15/3.27 event, the invasion of dust plumes greatly degraded the visibility over large areas of NC, with extreme low visibility 30 of 50m and 500m recorded at most sites on March 15 and 28, respectively. Despite the shorter duration of the 3.27 event relative
