Modeling dust mineralogical composition: sensitivity to soil mineralogy atlases and their expected climate impacts

Abstract. Soil dust aerosols are a key component of the climate system, as they interact with short- and long-wave radiation, alter cloud formation processes, affect atmospheric chemistry play role in biogeochemical cycles by providing nutrient inputs such iron phosphorus. The influence on these processes depends its physicochemical properties, which, far from being homogeneous, shaped regionally varying mineral composition. relative amount minerals source region shows large geographical variability. However, many state-of-the-art Earth system models (ESMs), upon which analyses projections rely, still consider mineralogy to be invariant. explicit representation ESMs is more hindered our limited knowledge global soil composition along resulting size-resolved airborne than computational constraints. In this work we introduce an within Multiscale Online Nonhydrostatic AtmospheRe CHemistry (MONARCH) model. We review compare two existing datasets, remain uncertainty for modeling provide evaluation multiannual simulations against available observations. datasets based measurements performed after wet sieving, breaks aggregates found parent soil. Our model predicts emitted particle size distribution (PSD) terms constituent brittle fragmentation theory (BFT), reconstructs destroyed sieving. broadly reproduce most abundant fractions independently data used. Feldspars calcite highly sensitive map, mainly due different assumptions made each dataset extrapolate handful arid semi-arid regions worldwide. For least or difficult-to-determine minerals, oxides, uncertainties yield differences annual mean aerosol mass up ∼ 100 %. Although BFT restores coarse including phyllosilicates that usually break during analysis, identify overestimation quartz (above 2 µm diameter). dedicated experiment, estimate fraction undetermined given makes 10 % at scale can larger. Changes underlying impact estimates climate-relevant variables, particularly affecting regional variability single-scattering albedo solar wavelengths total deposited over oceans. All all, assessment represents baseline future experiments new mineralogical maps constrained high-quality spaceborne hyperspectral measurements, those arising NASA Surface Mineral Dust Source Investigation (EMIT) mission.