Remote sensing of mineral dust from space: Inferring single scatter albedo and optical depth from a simulation of dust transport during the ACE-2 experiment

Assessing the climatic importance of mineral dust aerosols relies in part on deriving the aerosols' optical properties from satellite imagery. In order to investigate the spatial and temporal evolution of the dust particle size distribution we have incorporated an aerosol microphysical model into the NCAR Model for Atmospheric Transport and Chemistry (MATCH). With the inclusion of a detailed source scheme to calculate dust emissions, this combined model is used to simulate dust transport from the Sahara Desert during the ACE-2 experiment (June and July, 1997). The calculated dust fields are in good agreement with the in-situ data and ground-based extinction measurements collected during ACE-2. Radiative transfer calculations applied to the modeled dust fields are used to quantitatively compare the simulation to remotely sensed data. In particular, we consider the TOMS UV-absorbing aerosol index product, investigating the relationship between the dust layer height and the aerosol index as a means of determining the aerosol optical depth and single scatter albedo from observations.