Arid Shrubland: A growing dust source?

• The dust from the arid west coast of South Africa mainly originates from shrubland, bare lands, and mining areas • An increase in dust source points has been detected since 2017, which can be linked to a drought that affected shrublands. • Climate change could play an important role in the future development of dust emissions from arid regions. The west coast of South Africa is an arid region that has been shown to be emissive, but its dust sources have never been studied in detail. In this study, we present a dataset of the Moderate Resolution Imaging Spectroradiometer (MODIS)-detected dust source points in this region from 2000 to 2021 and the surface characteristics of these points. The results elucidate that most dust source points are located on Succulent Karoo shrublands, mining areas, or bare areas. Furthermore, the data show a significant increase in dust source points, which could mainly be attributed to shrublands becoming more emissive as a response to a prolonged drought from 2017 onwards. The Normalised Difference Vegetation Index (NDVI), Modified Soil Adjusted Vegetation Index (MSAVI), and albedo-based roughness indication (ωns) of the study area confirmed a decrease in vegetation during this five-year drought. Understanding such tipping points for dust emissions as a result of drought and anthropogenic land use is relevant to understanding the future dust load.