de Carvalho G. T. auteur aut IRD Pezzi L. P. auteur aut IRD Lefèvre Nathalie auteur aut IRD Rodrigues C. C. F. auteur aut IRD Santini M. F. auteur aut IRD Mejia C. auteur aut IRD text journalArticle eng text/pdf reformatted digital access The Southern Ocean (SO) plays a fundamental role in the planet's climate system, due to its ability to absorb and redistribute heat and CO2 (an important greenhouse gas). In addition, the SO connects three large oceanic basins the Pacific, the Atlantic, and the Indian Oceans, and it has an important role in the nutrient distribution in these oceans. However, the SO is poorly sampled, with most measurements made in austral spring and summer. The variability in the air-sea CO2 flux is estimated, as well as the role of atmospheric and oceanic variables in this variability. The CO2 fluxes are calculated using the bulk parameterization method, in the Atlantic sector of the Southern Ocean, from 2003 to 2022, using in situ measurements, satellites, and a reanalysis data set. A neural network model is built to produce maps of the partial pressure of CO2 in seawater (pCO(2sea)). The CO2 flux varies from -0.05 to 0.05 gC m(-2) month(-1). The Atlantic sector of the SO is a sink of CO2 in summer and spring and becomes a source in austral winter and autumn. The CO2 absorption intensifies from 2003 to 2022 by 7.6 mmol m(-2) month(-1), due to stronger westerly winds, related to the trend in the positive phase of the Antarctic Oscillation and the extreme El Niño Southern Ocean (ENSO) events (e.g., El Niño and La Ni ña). specialized air-sea interaction CO2 flux variability of CO2 fluxes Atlantic Ocean Southern Ocean ATLANTIQUE OCEAN AUSTRAL 021 16 3 319 [19 p.] 2025 https://www.documentation.ird.fr/hor/fdi:010092956 10.3390/atmos16030319 [F B010092956] https://www.documentation.ird.fr/hor/fdi:010092956 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2025-05/010092956.pdf IRD - Base Horizon / Pleins textes 2025-05-14 2025-11-04 fdi:010092956 fre