Our specific equations to calculate air-sea fluxes are laid out in detail in Wohl et al. . Here we provide a brief recap and additional details specific to benzene and toluene. Air-sea fluxes are calculated using the Liss and Slater (61) twolayer framework. Benzene and toluene fluxes are computed using the waterside transfer velocity from Nightingale et al. and the airside transfer velocity from Yang et al. . Freshwater solubilities (dimensionless water over air) for benzene and toluene listed in Wohl et al. were converted to seawater solubilities at the temperature of ambient seawater as described in Johnson . The Schmidt number for toluene was calculated using the supplementary R code from Johnson . The Schmidt number for benzene was calculated from the diffusivity of benzene and assuming the same temperature dependence as toluene. Saturations (see equation 1 in Wohl et al. ) were not computed if the hourly air mole fraction is near or below zero (defined as less than one measurement noise) to avoid unrealistic values. Calculated fluxes were scaled linearly to the open water fraction as recommended by Prytherch et al. . To do this, the underway SIC was used as derived from AMSR2 satellite. DMS and isoprene concentrations and fluxes were also measured during both deployments. Their concentrations are shown elsewhere and used here to test for correlations with benzene and toluene.