Winter season Southern Ocean distributions of climate-relevant trace gases

• Main Authors: Zhou, Li, Booge, Dennis, Zhang, Miming, Marandino, Christa A.
• Format: Article in Journal/Newspaper
• Language: English; German
• Published: Copernicus Publications (EGU) 2022
• Subjects: Southern Ocean
• Online Access: https://oceanrep.geomar.de/id/eprint/55974/; https://oceanrep.geomar.de/id/eprint/55974/13/bg-19-5021-2022.pdf; https://oceanrep.geomar.de/id/eprint/55974/14/bg-19-5021-2022-supplement.pdf; https://oceanrep.geomar.de/id/eprint/55974/25/invoice_Helmholtz-PUC-2022-101.pdf; https://doi.org/10.5194/bg-2022-106; https://doi.org/10.5194/bg-19-5021-2022

Climate-relevant trace gas air-sea exchange exerts an important control on air quality and climate, especially in remote regions of the planet such as the Southern Ocean. It is clear that polar regions exhibit seasonal trends in productivity and biogeochemical cycling, but almost all of the measurements there are skewed to summer months. If we want to understand how the Southern Ocean effects the balance of climate through trace gas air-sea exchange, it is essential to expand our measurement database over greater temporal and spatial scales, including all seasons. Therefore, in this study, we report measured concentrations of dimethylsulphide (DMS, and related sulphur compounds) and isoprene in the Atlantic sector of the Southern Ocean during the winter to understand the spatial and temporal distribution in comparison to current knowledge and climatological calculations for the Southern Ocean. The observations of isoprene are the first in the winter season in the Southern Ocean. We find that concentrations and fluxes of DMS and isoprene in the investigated area are generally lower than those presented or calculated in currently used climatologies and models. More data is urgently needed to better interpolate climatological values and validate process-oriented models, as well as to explore how finer measurement resolution, both spatially and temporally, can influence air-sea flux calculations.