Dust aerosols constitute over half of atmospheric aerosols. They not only influence weather and climate but also play a vital role in marine ecosystems and global material cycles. Dust aerosols directly affect the Earth-atmosphere system’s radiative energy budget by scattering and absorbing solar radiation and surface longwave radiation, producing direct climatic effects. They can also serve as cloud and fog condensation nuclei, altering their optical properties and inducing indirect climatic effects. Furthermore, dust aerosols reduce visibility, harm human health, and cause significant property damage. The Taklimakan Desert, a crucial dust aerosol source region for China and East Asia, has garnered considerable attention. Dust storms driven by dynamic uplift are considered the primary source of dust aerosols. However, current simulations consistently show dust fluxes far below observed values, indicating a substantial missing mass of dust aerosols. Thermal uplift mechanisms, such as dust devils, complement dust storm uplift mechanisms, jointly affecting dust aerosol concentrations over desert regions.  

To address this, Ma Mingjie from Institute of Desert Meteorology, China Meteorological Administration, Urumqi, along with the Desert Boundary Layer Meteorology research team, utilized meteorological and intensive dust devil observation data from the Xiaotang area (a desert transition zone on the northern edge of the Taklimakan Desert) and GPS sounding data from the Tazhong area (in the desert’s hinterland). They conducted observations and improved the parameterization scheme for dust devil emissions, aiming to reassess the contribution of dust devils to dust aerosols based on the enhanced scheme.  

The study reveals that the optimal near-surface temperature difference (between the surface and 2 m height) for dust devil formation is 16°C, with an optimal ambient wind speed range of 3.2–3.6 m/s. The improved parameterization significantly enhances the thermodynamic efficiency of dust devils compared to the original scheme. From 9:00 to 17:00, efficiency increased by 84.7%, 63.9%, 25.6%, 13.3%, 12.5%, 22.7%, 26.6%, 26.9%, and 21.4%, respectively. The number of dust devil occurrences under the improved scheme reached 431, a 55.2% increase over the original. The total duration of dust devil activity was 181.3 hours—95.5% shorter than the original scheme’s daytime duration but 31.8% longer than its sunshine duration. The average vertical dust emission flux per dust devil under the improved scheme was 0.25 g/(m²·s), 68.8% lower than before. The annual average dust emission per square kilometer was 15.3 tons, approximately 1/20th of the original estimate. Using the improved dust devil emission parameterization, the contribution of dust devils to dust aerosols was reassessed at 46.5%. This enhancement improves model simulation accuracy and reduces false alarm rates in current regional dust storm forecasting models.  

These findings were published in “Theoretical and Applied Climatology” under the title "Improvement of dust emission parameterization scheme for dust devils based on intensive observations in the Taklimakan Desert." The first author is Ma Mingjie, Assistant Researcher at the Institute of Desert Meteorology, China Meteorological Administration, Urumqi. The study received support from the Autonomous Region Youth Science Foundation Project and the Xinjiang Tianshan Youth Talent Program.  

Original article information: Ma Mingjie, Yang Xinghua, He Qing, Ali Mamtimin. 2023. Improvement of dust emission parameterization scheme for dust devils based on intensive observations in the Taklimakan Desert.  

Article link: https://doi.org/10.1007/s00704-022-04258-3.