Positive Feedback of Dust Direct Radiative Effect on Dust Emission in Taklimakan Desert

Abstract

Abstract Dust direct radiative effect (DDRE) can modify the near‐surface air temperature, which can in turn influence dust emission. However, the feedback mechanism of DDRE on dust emission is poorly understood. In this study, the influence of DDRE on dust emission in Taklimakan Desert (TD) was investigated using comprehensive ground‐based observations. The results show that the near‐surface air temperature significantly decreased as a result of DDRE, corresponding to dust emission enhanced. Statistically, the contributions of DDRE to dust emission during light, moderate, and heavy dusty episodes were 5.0% (3.6%), 5.2% (2.8%), and 6.1% (3.3%) in spring (summer), respectively. From the perspective of mechanism, DDRE can induce an increase in air density by cooling the near‐surface, causing an enhancement of aerodynamic drag, promoting dust emission in TD. Such positive feedback of DDRE on dust emission may be a potential contributor to improving the dust emission scheme of numerical modeling in the future.

Keywords

• dust direct radiative effect
• air temperature difference
• dust emission
• Taklimakan Desert