Downwind dispersion of CO ₂ from a major subsea blowout in shallow offshore waters

Growing interest in offshore geologic carbon sequestration (GCS) motivates risk assessment of large-scale subsea CO2 well blowouts or pipeline ruptures. For major leaks from wells pipelines, significant fluxes may occur the sea surface depending on water depth. In context human health and safety, we have used previously simulated coupled well-reservoir column model results as a source term for dense gas dispersion above surface. The models are linked together by one-way coupling, that is, output one is input to next model. These first-of-their-kind flow applicable assessing hazard people at downwind location emission. Hazard quantified plotting length (DDL), which define study distances emission point emitted has been diluted 5% 1.5% air volume. Results suggest shallow (10 m) cause hazardous plumes extending order several hundred meters downwind. Details modeling show DDL maximum windspeed (at an elevation 10 approximately 5 m/s, with smaller both weaker stronger winds. This explained fact wind favors transport but also causes dispersion; therefore there certain speed maximizes DDL. © 2022 Society Chemical Industry John Wiley & Sons, Ltd.