Very short lived halocarbons, as bromoform (CHBr3), dibromomethane (CH2Br2) and methyl iodide (CH3I) are naturally produced in the oceans and are involved in ozone depletion in the stratosphere. Their global oceanic emissions, based on the projected input parameters of three different CMIP5 models (MPI-ESM-LR, CESM1-CAM5 and HadGEM2-ES) show an increase from 2006-2100 for the RCP 2.6 and 8.5 scenarios, which is most pronounced at high latitudes due to increasing temperature and wind speed. The predicted emission increases are up to 30 % for the RCP 8.5 scenario. We show that the projected emission increases will lead to enhanced stratospheric bromine and ozone depletion by the combination of increased halocarbon emissions and the increase of vertical transport into the tropical stratosphere.

The future emissions were calculated with fixed oceanic and atmospheric concentrations over a period of 120 years, which imply increasing oceanic halocarbon production. While the influence of future ocean productivity changes on the oceanic halocarbon production rates and concentrations are currently unclear, additionally, other halocarbon sources in the ocean due to anthropogenic influences need to be taken into account, further increasing the sources. The future emission estimates are needed as input for chemistry climate models to better evaluate the future entrainment of oceanic halogens into the stratosphere and their influence on the chemistry and the recovery of the ozone layer.