Three-decade Dust trend (1988-2021) over the Continental United States

Aeolian dust exerts myriad effects on regional and global climate, public health and many socioeconomic sectors. This study examines the long-term trend of dust activity in the continental US., using a satellite-aided dust detection algorithm to reconstruct dust records from continuous aerosol observations collected by the Interagency Monitoring of Protected Visual Environments (IMPROVE) network. To identify dust storm events, we employ multiple cluster analysis methods, coupled with dust composition analysis during satellite observed dust events. These events exhibit the following characteristics: (1) high PM10 concentrations; (2) low PM2.5/PM10 ratio; (3) higher concentrations and percentage of crustal elements; (4) lower percentage of anthropogenic elements. From 1989 to 2022, there are 24 sites in the western US that meet the data completeness criteria. Frequency and intensity of dust events are then analyzed to explore whether the dust has experienced an increasing or decreasing trend. We also examine the spatial and temporal shifts of dust seasons in the western United States. Finally, climate drivers affecting the dust trend are investigated to understand the long-term variations of dust activity in this region and its connection with large scale Earth system changes.