Comparison of Dust Storm Events between East Asia and North America

Collaborative Innovation Center for Western Ecological Safety, College of Atmospheric Sciences, Lanzhou University, 730000 Lanzhou, China

^* Corresponding author: hjp@lzu.edu.cn

Abstract

In this study, the decadal variations of global dust storm events (DSEs) are studied based on two typical cases that occurred in East Asia in 2023 and in North America in 1934, respectively. We found that the periods with weak winter monsoon, varied jet stream, weakened Siberian High (SH) and strengthening atmospheric blocking corresponded to the high incidence of DSEs in East Asia. In recent years, activity of the East Asian DSEs is active again because of the mutual effect of these four systems. Due to the ecological engineering projects in China, the frequency of the DSEs is less than that in Mongolia, whereas in Mongolia, the land degradation causes the frequency of DSEs to increase significantly. In the Great Plains of the United States, high incidence of the DSEs mainly corresponded to periods with strong atmospheric blocking in North America. Since the 1860s, the Great Plains had been affected by destruction of vegetation and drought, with bare soil swept into the air by the strong winds, resulting in “Dust Bowl” in the 1930s. Under the warning of long-term strong DSEs, the U.S. government issued a series of policies to respond to the impact of DSEs, which improved the ecosystem of the Great Plains. As a result of the improved ecosystem and weaker blocking activities in the Great Plains in the 1950s, activity of the DSEs was significantly weaker than that in the 1930s.