Modelling the mechanisms and drivers of the spatiotemporal variability of pCO2 and air–sea CO2 fluxes in the Northern Humboldt Current System

•Air–sea CO2 fluxes follow the upwelling intensity throughout the year.•Circulation is the dominant mechanism driving variability in the nearshore area.•Biology and solubility effects partially damp upwelling-driven pCO2 variability.•High coastal pCO2 values are due to a spatiotemporal decoupling between circulation and biology.•pCO2 is more sensitive to changes in dissolved inorganic carbon and temperature.