Dust source activation frequency across East Asia

Abstract

Plumes of mineral dust in East Asia deleteriously impact the health and livelihoods of hundreds of millions of people in Mongolia, China, Korea, and Japan and perturb Earth’s energy balance and climate. However, the sources of this dust are not well-documented, limiting understanding of dust emissions. Here, we systematically quantify dust source activation frequency (DSAF) across East Asia (80–130° E; 27–52° N) between January 2016 and December 2023. Our data reveal a vast dust-active area extending from the Tibetan Plateau (TP) in the southwest to the Huin Bair Sandy Land in the northeast, but two regions dominate: southern sources centered on the margins of the Taklimakan Desert and northern ones centered on the valleys of the Gobi Desert. East Asia is most dust-active in boreal spring (46% of all recorded events). This seasonal peak is pronounced in northern sources where snow cover, vegetation and orographic/topographic influence on winds are clear controls on DSAF. The main southern sources are active year-round with DSAF hotspots attributable to desiccated lakes and riverbeds. The TP, commonly considered a sink for in-bound windblown dust, is also a dust source, particularly in winter, with emissions controlled by precipitation patterns, snow cover and wind funneling through deep river gorges. Contrary to suggestions, our data show that the Loess Plateau is not a major dust source. We document a marked increase in dust source activation during the 2020 extreme heat wave on the overgrazed Mongolian Plateau grasslands. Our data provide a framework to study past variability in the two-way climate interactions that control dust emissions on historical and geological timescales and a baseline from which to measure future change.