Description
Summary:11 pages, 4 figures, 1 table, supplementary information https://doi.org/10.1038/s41467-024-46744-4.-- Data availability: All the data from the ACE campaign can be found in the ACE Zenodo online repository39 at https://zenodo.org/communities/spi-ace/ (last accessed: 15 August 2023). Ambient isoprene mixing ratios are available from Bolas et al.68 https://zenodo.org/records/5674685. The URLs for other datasets used in this work are provided within the text and references for the Methods section. All model data are freely available at the Zenodo repository https://doi.org/10.5281/zenodo.8184979 and https://zenodo.org/records/8184980.-- Code availability: Due to intellectual property right restrictions, we cannot provide either the source code or documentation papers for the UM. The Met Office United Model is available for use under licence. A number of research organisations and national meteorological services use the UM in collaboration with the UK Met Office to undertake atmospheric process research, produce forecasts, develop the UM code, and build and evaluate Earth system models. For further information on how to apply for a licence, see https://www.metoffice.gov.uk/research/approach/modeling-systems/unified-model (last accessed: 20 Dec 2023) Isoprene is a key trace component of the atmosphere emitted by vegetation and other organisms. It is highly reactive and can impact atmospheric composition and climate by affecting the greenhouse gases ozone and methane and secondary organic aerosol formation. Marine fluxes are poorly constrained due to the paucity of long-term measurements; this in turn limits our understanding of isoprene cycling in the ocean. Here we present the analysis of isoprene concentrations in the atmosphere measured across the Southern Ocean over 4 months in the summertime. Some of the highest concentrations ( >500 ppt) originated from the marginal ice zone in the Ross and Amundsen seas, indicating the marginal ice zone is a significant source of isoprene at high latitudes. Using the ...