Dust observation by a ground-based lidar network along the global dust belt

Abstract

It is proven that there is a macro dust belt over the Northern Hemisphere, extending from northern Africa to East Asia. The dust emissions from the dust belt can reach up to around 2100 Tg/year. The Saharan desert is the largest contributor to the dust belt, accounting for about 50-60% of the total global dust. Our study indicates that Saharan dust can be transported to the upper troposphere in East Asia, contributing a substantial dust 22.88-44.94 Tg/year. It provides a new perspective on the important role of Saharan dust over East Asia. Climate variability has a significant impact on these regions, so that, it is needed to know how the aerosol particles change in the region in the context of global warming. Aiming to obtain the vertical distribution of dust aerosol and clouds, we have initiated a ground-based lidar network along the dust belt since 2018. Dust events were observed by the ground-based lidar at Tazhong station in 2021 and Ruoqiang station in 2020. We characterized the vertical distribution of these dust events. In the future, the lidar network is expected to establish 15 sites before 2024, extending from China to Northern Africa. The ground-based lidar system in the lidar network is a multi-wavelength Mie-Raman polarization lidar developed by Lanzhou University for continuously detecting water vapor, aerosols and clouds. To better assess the climate effect of dust aerosol over the region, other advanced instruments, such as sun-photometer, microwave radiometers, PM10/PM2.5 monitoring device, automatic meteorological station etc., are installed at each lidar site. The lidar network will provide continuous observational data of aerosols and clouds, which helps to better understand climate change in the region.