Numerical Analysis of an Early-Arriving East Asian Dust Storm in 2026: Evaluation, Size-Resolved Dust Contribution, and Source Attribution

Mineral dust aerosols profoundly influence regional climate and air quality, yet large uncertainties persist in numerical dust modeling, particularly in the dust emission process, dust mass distribution analysis, and the quantification of source-specific contributions. This study focuses on an early-arriving East Asian dust storm that occurred during 18–23 February 2026 and extended to the Yangtze River Basin. Using a modified WRF-Chem model coupled with three dust emission schemes (GOCART, Shao2001, and KOK), GOT_EF0.5 performs best in capturing the spatial pattern and intensity of the observed AOD, attaining the highest R of 0.74 and the lowest RMSE of 0.16. Size-resolved analysis based on GOT_EF0.5 reveals that the event was heavily dominated by coarse dust particles. Dust size bins 5–8 contribute over 90% of the total dust mass to surface PM10, with bins 6 and 7 dominating long-range transport and bin 8 contributing mainly near source regions. Dust mass distribution analysis shows that regional dust emissions peaked on 20 February at over 4.0 Tg, whereas the area-averaged dust loading peaked 24 h later on 21 February at approximately 90 mg/m2, highlighting a distinct temporal hysteresis during downstream transport. Source attribution further demonstrates that the Gobi Desert is the predominant contributor, accounting for approximately two-thirds of the total dust loading during the event, whereas the Taklimakan Desert and other peripheral sources play only secondary, localized roles. These findings highlight the importance of the dust emission scheme in dust simulation, the quantitative basis for improving dust size-resolved forecasting, and the identification of the different desert contributions to a specific dust storm.