Abstract. We calculate the global change in the production of tropospheric ozone (O3) and loss of methane (CH4) caused by 45 d of summertime South Korean anthropogenic emissions during the Korea-US Air Quality (KORUS-AQ) mission. Our modelling system consists of three stages: the boundary layer-residual layer (BL-RL) stage processes the emissions, photochemistry, deposition, aerosol reactivity, and transport over terrestrial South Korea at 0.1° × 0.1° with hourly resolution. The plume (PL) stage