Long-term variations in spatiotemporal clustering characteristics of dust events in potential dust sources in East Asia

Abstract

Dust storms, originating in desert areas of China and Mongolia, have long been a primary environmental concern in East Asia and beyond. Even though the frequency of dust storms has been steadily decreasing since the 1980s, the spatiotemporal clustering and variability of dust events, including floating dust (FD) and dust outbreak (DO), remain poorly quantified and studied in the context of climate change. Therefore, in this study, we analyzed the spatiotemporal clustering characteristics of dust events and explored the possible correlation between long-term variations in surface vegetation and dust events in potential dust source (PDS) regions in East Asia, mainly China and Mongolia. As a result, the interannual, intermonth, and peak season variability in China is lower than that in Mongolia. In China, the peak seasons of FD are longer than that of DO. In Mongolia, however, a contrary scenario is observed, where the peak seasons of FD has been gradually prolonged. Significant increasing trend mainly distributed in the Taklimakan Desert, along the north of the Yellow River, and in the north Gobi Desert. By examining the transfer trajectory of gravity center of dust events, it indicates that the gravity centers of FD and DO in China have been transferring from the east to the west of the Taklimakan Desert and the Badain Jaran Desert, respectively; and in Mongolia, the gravity center of FD has been shifting from the south to the northwest in the Gobi Desert, while the gravity center of DO has been gradually moving eastward near Ulaanbaatar. Furthermore, higher vegetation coverage is positively correlated with suppressed dust activity. These findings would provide a reliable scientific foundation for measures to prevent dust disaster and to mitigate the negative effects of dust events, and practical guidelines for safeguarding and strengthening human settlements.