The Use of Satellite Aerosol Optical Depth Snapshots to Constrain Biomass Burning Aerosol Emissions in the GOCART Model: Method Update

We rely upon aerosol transport models to represent the impacts of biomass burning (BB) particles, such as wildfire smoke, on climate and health. These models depend on external emission inventories to simulate the location and strength of BB sources. However, estimates of aerosol amounts differ considerably among emission inventories globally, and even more so on regional scales. We introduced a method using snapshots of MODIS-measured aerosol optical depth (AOD) to constrain BB emissions in the GOCART model (M. M. Petrenko et al., 2012, JGR). We use the quantitative relationships derived to correct the emission estimates. We build on this approach, addressing some limitations of the method, and applying corrections based on the results to the BB emissions used in the GOCART chemical transport model. For example, we increased the number of smoke cases studied to enhance statistical significance in under sampled regions. We also use MODIS AOD in combination with MISR AOD to improve the over-land satellite AOD constraints. We will present our assessment of the performance of the corrected emissions in the model. This assessment is based on both comparing the satellite and model AOD for the cases used to develop the correction, as well as evaluating the results for a "validation dataset" - a collection of fire cases from a different year, which were not included in deriving the emission-correction coefficients. We expect this method for correcting BB aerosol emissions to be useful to aerosol modelers as well as developers of emission inventories.