To What Extent Biomass Burning Aerosols Impact South America Seasonal Climate Predictions?

We applied the Goddard Earth Observing System for subseasonal to seasonal climate prediction to assess the impact of inclusion biomass burning (BB) aerosols over South America (SA) during the austral winter. We also evaluated the model sensitivity to the BB emissions prescription using no emissions, monthly climatological, and daily emissions. Each hindcast consisted of four members running from June to November of each year between 2000 and 2015. Our results indicated that interactive BB aerosols improve the seasonal climate prediction performance over SA. More realistic daily based emissions significantly further improve the performance in comparison with the climatological ones. Therefore, improvements in the BB emissions representation are urged to represent the aerosol impacts on seasonal climate prediction performance adequately. Plain Language Summary Vegetation fires severely affect tropical forest and savannah-type biomes in South America (SA) during winter in Southern Hemisphere. Biomass burning (BB) aerosols are important agents changing energy budget and clouds. This study focused on assessing whether including aerosol-radiation-cloud interaction in a climate model, particularly the contribution of BB aerosols, can provide additional information for improving seasonal climate predictions. This study has two primary outcomes. First, that including BB aerosols does improve the model's ability to predicted precipitation and near-surface temperature in SA. Second, it proved it is indeed essential to improve BB emissions representation to further elevate seasonal climate prediction performance.