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Absorbing aerosols, including black carbon (BC) and dust, play an important role in regional and global climate by heating the air column and modifying the horizontal and vertical temperature gradient, atmospheric stability, and convection strength.Dust is an important aerosol source, which cover the sky over Africa, the equatorial Atlantic Ocean, Middle East, South Asia, northern China, and the northwestern Pacific Ocean.The source and distribution of dust particles are closely regulated by topography.In the mountainous region (e.g., the Tibetan Plateau), important dust sources are often found in the surrounding intermountain basin (e.g., the Taklamakan desert).Using MODIS aerosol optical depth (AOD) and TOMS/OMI aerosol index (AI), we show that the main dust source in China is locally generated over its northwestern regions and north of the Tibetan Plateau, especially in spring.The Tibetan Plateau plays an important role in blocking the dust transported from North Africa, where a large amount of dust particles are carried by the general circulations to Europe and Middle East and across the Atlantic to the southeastern United States, leading to the formation of a major dust belt.The high AI values in other areas of China are mostly due to BC associated with coal production.