Identification of dust aerosol source areas and transmission paths along the China–Pakistan Economic Corridor

Dust aerosols significantly impact the global climate, ecological environment and human health. Clarifying the distribution changes, sources, and transport routes of dust aerosols along the China–Pakistan Economic Corridor is important for assessing regional atmospheric environments and ensuring sustainable development. This study uses MODIS aerosol data, meteorological reanalysis data from 2003 to 2023, and the HYSPLIT model to reveal the characteristics and trends of aerosols and dust aerosols, quantify the distributions of dust sources, and estimate dust emissions. Results reveal ①Dust aerosols exhibit significant seasonal variations: summer (0.66)> spring (0.58)> autumn (0.37)> winter (0.29), and high-value areas are concentrated in eastern and southern Pakistan. The proportion of areas with increasing dust aerosol optical depth (DAOD) is 2.92%. ②Pakistan’s Balochistan and Sindh Provinces, and China’s Xinjiang Kashgar Region, are the main dust sources. Dust emissions from natural surfaces are high in spring, while those from anthropogenically influenced surfaces are peak in summer. ③In spring, air mass transport pathways are dominated by short-distance southeastward transport (75%), while long-distance northeastward transport occurs across all four seasons.