Quantifying Remote Source Contributions and Radiative Forcing of Airborne Dust Over East Asia With CALIPSO Observations

Abstract A thorough understanding of the sources, contributions, and transport pathways of airborne dust over East Asia is essential for evaluating its regional climatic and environmental impacts. Although widely used, numerical models yield uncertain dust loading estimates in receptor regions due to uncertainties in emission and deposition parameterizations. This study combines Cloud‐Aerosol LiDAR and Infrared Pathfinder Satellite Observations data with a dust activity‐constrained source‐tracing algorithm to investigate dust sources over East Asia, and assesses associated radiative forcing using a radiative transfer model. Airborne dust over East Asia originates from multiple Northern Hemisphere sources. Based on dust occurrence frequency, the dominant contributor is the Gobi Desert (GD, ∼30%), followed by the Taklimakan Desert (TD, 8%–16%), Western Central Asia (WCA, ∼10%), and West Asia‐South Asia/Middle East‐North Africa sources (WA‐SA/ME‐NA, 5%–8% in southern East Asia). Contributions from remote sources exhibit marked vertical heterogeneity: GD dust accounts for over 50% of dust extinction below 5 km in northern East Asia and below 2.5 km in southern East Asia, whereas other sources contribute 5%–37% above these respective altitudes. Transport heights increase with source distance, ranging from 2–4 km for GD to 5–7 km for WA‐SA and ME‐NA clusters. Mean annual cumulative net radiative forcing transitions from cooling below 5 km to warming above, with GD contributing a peak cooling of −5,775 W m −2 near 1.5 km over North China and distant sources contributing 13–36 W m −2 of upper‐tropospheric warming over southeastern China. These results provide a foundation for evaluating source‐specific dust impacts on East Asian climate and air quality.

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