Characterization of Mineral Dust Absorption, Height and Composition from DSCOVR EPIC Using MAIAC Algorithm (Invited Presentation)

Located in unique L1 point, the DSCOVR EPIC instrument makes high-cadence observations of the illuminated disk of Earth in the UV, visible and near-IR range of wavelengths. EPIC’s UV-Vis and atmospheric oxygen A- and B-bands allow us to derive aerosol absorption and height information for mineral dust and smoke aerosols. The novel version 3 MAIAC algorithm for processing DSCOVR EPIC data includes joint retrievals of the aerosol optical depth, spectral absorption, and aerosol height (H^a). The reported parameters include H^a, AOD₅₅₀, imaginary refractive index k₆₈₀ and spectral absorption exponent (SAE) showing spectral change of k, along with single scattering albedo (SSA) at 340, 388, 443, 550, and 680nm. Evaluation of SSA shows good agreement with AERONET data, generally within the uncertainty of AERONET SSA of ± 0.03. Using derived optical properties, we further retrieve volume and mass fractions of main dust absorbers – hematite and goethite – assuming spectral refractive indices. Based on the EPIC data record from 2015, we will present an initial assessment of multi-year climatology of global mineral dust optical properties and hematite/goethite distribution.