HUMAN-INFLUENCED DUST EMISSIONS IN UTAH’S GREAT BASIN FROM 2004 - 2024

Anthropogenic activities play an important role in dust emission potential and understanding how these activities contribute to dust emissions will aid in predicting dust events and in choosing mitigation strategies while contributing to the global dust emission models. The Great Basin of Utah is a known source of dust production, but limited research exists on the impact of human influence contributing to the emission of dust in the region. This study investigates anthropogenic dust sources (disturbance of the soil due to vehicles, cattle trampling, agricultural practices, and other activities) over the past 2 decades (2004 - 2024) in the eastern Great Basin using Moderate Resolution Imaging Spectroradiometer (MODIS) data, land cover data, and meteorological data. In the basin, spring months are notable for increased dust events, which correspond to higher winds and the trajectory for some of these storms are towns and urban centers, including Delta and Salt Lake City. Dust point sources occur as single, broad, or zonal sources, and these sources were tied to specific land uses. Analysis of land use reveals that over two decades, the area covered by water, primarily the Great Salt Lake, declined by 3.3% and barren land increased by 1.1%. The area of cropland decreased by 10.1%, shrub/scrub decreased by 0.4% and grassland increased by 14.0%. The changes were primarily driven by increases in water use and urban expansion and multidecadal drought. Consequently, preliminary analysis of dust source mapping reveals that barren land produced most dust plumes. With 172 visible dust plumes, barren land is a primary source of dust in this region due to the lack of vegetative cover combined with human disturbance due to off-highway vehicles and military activities. Barren lands close to cultivated lands were likely disturbed or reactivated during farming. 102 plumes were observed on shrub/scrub, while cropland had three plumes. This study will further elucidate human versus natural dust production within the Great Basin, where proper monitoring and sustainable management of land use practices in this region is needed.