Hurricanes trigger ocean CO2 uptake and phytoplankton bloom in a high-resolution Earth system model simulation

North Atlantic tropical cyclones (i.e. hurricanes) are observed to drive intense air-sea CO₂ exchange and trigger primary production by phytoplankton. However, Earth system models (ESMs) with coarse spatial resolution are not able to capture such effects. Here, we address this limitation and resolve the impacts of hurricanes on the ocean carbon cycle in an ESM for the first time. We present the first 1-year global, coupled, high-resolution (5 km ocean, 5 km atmosphere) ESM simulation including ocean biogeochemistry with the ICON (ICOsahedral Non-hydrostatic) model framework. Our simulation realistically reproduces the effects of hurricanes at: 1) instantaneously increasing air-sea CO2 fluxes by a factor of 10-30 due to strong surface winds (>58 m/s, hurricane category 4); 2) promoting longer-lasting surface ocean cooling by 2-4°C, and thus decreasing surface ocean partial pressure of CO₂ (pCO₂); and 3) triggering large-scale phytoplankton blooms, spatially modulated by mesoscale ocean eddies. We show that the hurricane-driven sea-surface cooling is mainly caused by extreme latent heat loss (>1200 W/m²), whose impact on decreasing pCO₂ outweighs the mixing and upwelling of dissolved inorganic carbon. Our simulated hurricanes contribute to inverting the direction of the local air-sea pCO₂ imbalance, thus promoting ocean CO₂ uptake. Intense wind speeds also trigger vertical diffusion of nutrients, as well as near-inertial oscillations, which become the dominant mode of subsurface ocean variability in the wake of the cyclones. While the proportion of intense tropical cyclones is projected to increase with climate change, their future role in the ocean carbon cycle remains unclear. Resolving tropical cyclones in ESMs will allow us to better understand their response and impact to ongoing climate change at regional and global scales.