The interactions between biogenic volatile organic compounds (BVOCs), like isoprene and monoterpenes, and anthropogenic emissions of nitrogen and sulfur oxides lead to high concentrations of secondary organic aerosol (SOA) in the southeastern United States. To improve our understanding of SOA formation, we study the diurnal evolution of SOA in a land-atmosphere coupling context, based on comprehensive surface and upper air observations from a characteristic day during the 2013 Southern Oxidant and Aerosol Study (SOAS) campaign. We use a mixed layer model (MXLCH-SOA) that is updated with new chemical pathways and an interactive land surface scheme that describes both biogeochemical and biogeophysical couplings between the land surface and the atmospheric boundary layer (ABL). MXLCH-SOA reproduces observed BVOC and surface heat fluxes, gas-phase chemistry and ABL dynamics well, with the exception of isoprene and monoterpene mixing ratios measured close to the land surface. This is likely due to the fact that these species do not have uniform profiles throughout the atmospheric surface layer, due to their fast reaction with OH and incomplete mixing near the surface. SOA formation from isoprene through the intermediate species IEPOX and ISOPOOH is in good agreement with the observations, with a mean isoprene SOA yield of 1.8 %, and mean monoterpene yield of 10.7 %. However, SOA from monoterpenes, oxidized by OH and O 3 , dominates the locally produced SOA (69 %). Isoprene SOA is produced primarily through OH oxidation via ISOPOOH and IEPOX (31 %). A sensitivity analysis of the coupled land surface-boundary layer-SOA formation system to changing temperatures reveals that SOA concentrations are buffered under increasing temperatures: a rise in BVOCs emissions is offset by decreases in OH concentrations and the efficiency with which SVOCs partition into the aerosol phase.