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Dust devils are vertically oriented, columnar vortices that form within the atmospheric convective boundary layer (CBL) of dry regions. They are able to lift a sufficient amount of soil particles including dust to become visible and are considered as a potentially important dust source for the atmosphere. Mineral dust, a key component of atmospheric aerosols, influences the climate by affecting the radiation budget and cloud formation. Current estimates of the contribution of dust devils to the global, regional, and local dust release vary considerably from less than 1% to more than 50%. To address this uncertainty, we perform the highest resolved large‐eddy simulation (LES) study on dust emission in the CBL to date, using the PALM model system and the saltation‐based Air Force Weather Agency (AFWA) dust emission scheme. Our results show that under desert‐like conditions, dust devils are responsible for an average of 5% of regional dust emissions, with temporary maxima of up to 15%. This contrasts with previous measurement‐based (>35%) and LES‐based estimates (∼0.1%). Local emissions of dust devils (up to 10 mg m−2 s−1) are 1–3 orders of magnitude higher than the emission in the surroundings. This makes dust devils important for air quality and visibility. Additionally, our study reveals previously unknown large‐scale convective dust emission patterns. These patterns are tied to the CBL's cellular flow structure and are the main cause of dust release. Contrary to other studies, our findings clarify the important role of saltation‐induced dust emission. Plain Language Summary: Dust devils, vertically oriented convective vortices frequently observed in arid and semi‐arid regions, are potential contributors to the atmospheric dust. This airborne dust has significant implications for climate, as it can alter the radiation budget and influence cloud formation. The exact proportion of atmospheric dust originating from dust devils is currently under debate, with widely varying estimates. To address this uncertainty, we used an advanced turbulence‐resolving large‐eddy simulation model, the PALM model system, combined with the saltation‐based Air Force Weather Agency's dust emission scheme. Our results showed that under desert‐like conditions, dust devils account for an average of 5% of regional dust emissions. Peaks can reach up to 15%. Notably, these figures challenge both previous measurement and simulation‐based assessments. Additionally, our study found that dust devils produce local dust emission fluxes up to 1–3 orders of magnitude higher than ambient values. This suggests a notable effect on air quality and visibility. Moreover, we identified large‐scale patterns of dust emission linked to the flow structure of the convective boundary layer. These patterns emerge as the primary contributors to the regional dust release. Our study underscored the importance of understanding saltation‐induced dust emission and the role of dust devils in the atmosphere. Key Points: Dust devils cause peak dust emission fluxes of 46.7 mg m−2 s−1, which is 1–2 orders of magnitude larger than previous numerical estimatesDust devils contribute an average of 5% to the total dust emission of the simulated domain, with instantaneous contributions of up to 15%Saltation‐induced dust emission is arranged in large‐scale patterns that are related to the polygonal convection cells of the boundary layer [ABSTRACT FROM AUTHOR]

Wind erosion is a physical process predominated by airborne grains rather than the wind itself. The soil deformation is either elastic–plastic or fully plastic during its collisions with solid grains, corresponding to dense and loose soils, respectively. Only the fully plastic deformation was previously taken into account in the physically‐based wind erosion models. The impact erosion of dry and dense soil surface can be well quantified by the contact mechanics and strength theories. In this study, with the help of Owen's uniform saltation model, a simple expression for wind erosion rate is derived based upon the eroded volume per impact when soil deforms in the elastic–plastic manner. The new expression, a simple analytical function of several conventional variables and parameters of wind and soil, describes the effects of saltation flux and soil susceptibility. Its validity is verified by some field and laboratory experiments. [ABSTRACT FROM AUTHOR]

• Saltation bombardment is a main pattern of dust emission for compacted soils. • Wind tunnel was used to simulate the abrasion of compacted soils by blown sand. • Dust emission efficiency was positively correlated with the amount of abrader. • Clay and silt contents of soils had different influences on dust emission efficiency. • An integrated model of dust emission efficiency for compacted soils was established. Abrasion by blown sand is a main wind erosion process for compacted soils, such as dry lake basins and the undisturbed grassland that are widely distributed in arid land. Dust emission efficiency (δ) is defined as the ratio of the dust flux to the sediment transport rate from a soil surface. Previous studies mostly focused on the influence of wind velocity or soil properties on δ and rarely considered the amount of abrader in blown sand; furthermore, most of their experiments used loose soils involving three physical mechanisms of dust emission. In this study, we explored the mechanism of dust emission from compacted soils caused by saltation bombardment of the abrader making use of wind tunnel experiments and using the mass flux of the abrader (q) to represent the abrasion intensity of blown sand. The results showed that dust flux (F) generated from the compacted soil by abrasion and bombardment was linear with q , and δ was always positively correlated with q and with the silt and clay content in soils. Taking into account both the amount of abrader and the texture of the soil being abraded, we proposed and validated a model of dust emission efficiency for compacted soil. [ABSTRACT FROM AUTHOR]