The contribution of the world's main source regions to the global cycle of desert dust

Even though desert dust is the most abundant aerosol by mass in Earth's atmosphere, the relative contributions of the world's major dust source regions to the global dust cycle remain poorly understood. This problem limits both the interpretation of geological records of dust deposition, as well as the ability of models to account for regional differences in dust mineralogy for calculating dust impacts on clouds, radiation, and biogeochemistry. Here, we constrain the contribution of each of the world's major dust source regions to the global dust cycle. We do so by combining an ensemble of global model simulations with joint observational, modeling, and experimental constraints on the dust size distribution, extinction efficiency, and regional dust aerosol optical depth. Our results facilitate improved constraints on dust direct radiative forcing since pre-industrial times, as well as on dust impacts on clouds and biogeochemistry.