Modeling for the source apportionments of PM10 during sand and dust storms over East Asia in 2020

Abstract

Sand and dust storms occur frequently in East Asia, and the dust particles could be transported to most areas of East Asia. To quantify the dust emissions in 18 dust source regions in China and Mongolia and their contributions to PM10 concentrations over East Asia, 10 sand and dust storms (SDSs) episodes in 2020 were simulated using the Comprehensive Air Quality Model with Extensions (CAMx). A dust emission scheme and a tagged method were incorporated. The model well captured the variations of PM10 concentrations during the SDSs episodes. The Gobi deserts in Mongolia were the most important sources of sand and dust in East Asia, with the highest dust emissions, contributing more than 60% to the PM10 concentrations over East-Central China, Japan, and South Korea. The dust emission from Inner Mongolia was about 1/3 of that in Mongolia, and contributed 20–30% to PM10 concentrations over East-Central China, Japan, and South Korea. However, more than 50% of the PM10 concentrations in Inner Mongolia originated from Mongolia in the SDSs events. Few dust aerosols from Taklimakan and Eastern Xinjiang could be transported to the areas further than its surrounding area. Because of the larger contribution of Mongolia to Northern China, the variation of the dust storm frequency in Northern China correlated well with the surface conditions in Mongolia. Anthropogenic emissions contributed less than 5% to the PM10 concentrations over most part of East Asia during the SDSs events.