Exploring the Impact of Dynamic Dust Source on the East Asian Dust Cycle Using WRF-Chem

Abstract

Dust emission is a prerequisite to accurately describe the physical processes of dust and is closely associated with dust sources; however, the spatial and temporal variation of East Asian dust sources has not been accurately quantified. Herein, we show the effects of the dominant factors associated with the dynamic dust source on dust modeling with multiple aspects. We found that the dynamic dust source in East Asia in 2001–2020 demonstrates a pronounced monthly and annual variability, showing wider spatial distribution in March than that in July and lower probability of dust uplifting in summer than that in spring. The dust source functions of the Gobi Desert and Taklimakan Desert decrease at rates of 5.8 × 10⁻³ and 4.7 × 10⁻³ decade⁻¹, respectively. Using the Weather Research and Forecasting model coupled with Chemistry, we further assess the joint control of surface bareness and topographical depression feature on the spatial distribution and value of the dynamic dust source. The East Asian dust source function generally increases with increasing surface bareness threshold, whereas that in the western Taklimakan Desert and central Gobi Desert decreases with coarse topography calculation resolution. These study findings show the importance of the dynamic dust source on dust simulation and deeply dive into exploring the effect of surface bareness and topographical depression feature on dust cycle simulation, which provide more options for better dust simulations in the future.