In the value chain for CCS pipeline transport of CO2 and storage of CO2 underneath the ocean floor are key aspects. Failures in these can cause a subsea release of CO2 which will result in a bubble plume of CO2 rising to the surface. This affects the pH levels in the ocean and potentially poses a safety concern if released into the atmosphere. A mathematical model assessing the bubble plume will be presented. It accounts for mass transfer into the ocean since CO2 is very soluble. It also accounts for evaporation of CO2 droplets since the phase diagram dictates that for most scenarios the release will be a mixture of gas and liquid.