Transboundary transport of central Asian dust to the Pamirs: measurements and modeling

Tajikistan is located in an arid and semi-arid region, with a dry climate and sparse precipitation and the sandstorms frequently occur in summer. The Shaartuz lidar site (68.0°E, 36.9°N, 274 masl) is located in a basin in southern Tajikistan. It is observed that the dust storms occur in this area are usually lifted to a height of 5-6 km above the ground, which is equivalent to the height of the Pamirs covered with ice and snow. With the effects of complex terrain, there is a possibility of the dust being transported to the Pamirs under the mid-latitude westerly belt. In this work, the two lidar systems located in Shaartuz and Taxian (75.2°E, 37.8°N, 3087 masl) which is in the southeast of the Pamirs are utilized to study the dust event in summer. The significant variations of dust optical properties and vertical distribution can be captured by the two lidar system during June 11th to 15th, 2023. The backward trajectory model and satellite observation are used to verify the transport path of the dust event. WRF-Chem also successfully simulated the transport process of the dust event, and analyzed the spatiotemporal evolution characteristics and the dust effects. These results will help us explore the characteristics of central Asian dust transboundary transport toward Pamirs and its regional climate effects.