A super dust storm enhanced by radiative feedback

Abstract

As the main dust source area in East Asia, the Gobi Desert (GD) exerts critical impacts on the radiation budget in downstream regions. Dust radiative feedback in the GD on the Mongolian cyclone, however, remains poorly understood. Herein, the dynamic dust source is coupled with the Weather Research and Forecasting model with Chemistry (WRF-Chem) for better dust simulations. Results show that the Mongolian cyclone dominates the dust event in May 2019. Dust radiative feedback results in downward momentum transport and cools northeast of Mongolia by affecting zonal winds and temperature advection. Lower-troposphere cooling and upper-atmosphere warming change the atmospheric vertical structure and enhance baroclinicity. Further, cold air deeply descends into the bottom of the warm air in a wedge shape and promotes the ascension of warm air to enhance the Mongolian cyclone. The strong dust is maintained and continues to cause high dust concentrations in northern China via westerlies. This study explores how dust radiative feedback over the GD can intensify the Mongolian cyclone and provides a scientific reference for related studies.