Effect of dust aerosols on the heat exchange over the Taklimakan Desert

The Taklimakan Desert (TD), an important dust source over the world, has a significant impact on the weather and climate. In this study, the effect of dust aerosols on the heat exchange of Earth-Atmosphere system during a dust event over the TD is investigated by WRF-Chem model. The result shows that, during the dust event from 25–28 July 2019, the dust injected from the TD can be transported up to an altitude more than 6 km in the atmosphere. Over the TD, most portion of the surface net radiation ( R N ) is distributed to the sensible heat flux ( SF ), especially over the areas with dust emission and high dust concentration. The existence of dust aerosols can affect the R N and further influence the other components of the surface-air energy exchange. The R N is enhanced as well as the SF than that without dusts where emits dust strongly. While the dusts make the R N and SF lower than that without dusts during the dust transportation. The effect of dust on R N and SF varies at different stages of the dust event, and it causes consistent changes in R N and SF. Besides, the latent heat flux ( LF) exchange has a similar distribution with the SF over the TD except that the dusts exert less impact on LF . Additionally, the soil heat flux ( GF ) shows an opposite pattern to the SF , and the dust aerosols have less influence on the GF . Vertically, the shortwave radiation heating caused by dust aerosols over TD during the dust event is positive with a maximum of 0.25 K day −1 below an altitude of 6 km. Though some uncertainties may be introduced in the modeling, this study can provide a basis to understand the effects of dusts on the land-atmosphere energy exchange over the TD. • Dust emission and transport over Taklimakan Desert are successfully simulated. • Dusts have the greatest impact on the sensible heat flux during the dust event. • Effects of dusts on the heat exchange are revealed well.