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The state and dynamics of the oceans and seas that surround Africa are changing at an increasing pace due to anthropogenic pressures. The livelihoods of many Africans depend on fishing and ocean-​driven monsoon rains, and some African coastlines are eroding rapidly, potentially with catastrophic results to populations and infrastructure. Yet few African scientists are prepared to engage in ocean-related research. To address this deficit, the Master’s program in Oceanography and Applications1 was launched in 2008 in Benin, targeting the West African region. This program is designed to build capacity in support of regional research programs in oceanography such as PIRATA (Prediction and Research Moored Array in the Tropical Atlantic; Bourlès et al., 2019), AMMA-EGEE (African Monsoon Multidisciplinary Analyses - Oceanic Circulation and Ocean-​Atmosphere Exchanges in the Gulf of Guinea; Redelsperger et al., 2006; Bourlès et al., 2007), and PROPAO (Regional Program of Physical Oceanography in West Africa; Sohou et al., 2020). 

Surface ocean biogeochemistry and photochemistry regulate ocean–atmosphere fluxes of trace gases critical for Earth's atmospheric chemistry and climate. The oceanic processes governing these fluxes are often sensitive to the changes in ocean pH (or p CO 2 ) accompanying ocean acidification (OA), with potential for future climate feedbacks. Here, we review current understanding (from observational, experimental and model studies) on the impact of OA on marine sources of key climate-active trace gases, including dimethyl sulfide (DMS), nitrous oxide (N 2 O), ammonia and halocarbons. We focus on DMS, for which available information is considerably greater than for other trace gases. We highlight OA-sensitive regions such as polar oceans and upwelling systems, and discuss the combined effect of multiple climate stressors (ocean warming and deoxygenation) on trace gas fluxes. To unravel the biological mechanisms responsible for trace gas production, and to detect adaptation, we propose combining process rate measurements of trace gases with longer term experiments using both model organisms in the laboratory and natural planktonic communities in the field. Future ocean observations of trace gases should be routinely accompanied by measurements of two components of the carbonate system to improve our understanding of how in situ carbonate chemistry influences trace gas production. Together, this will lead to improvements in current process model capabilities and more reliable predictions of future global marine trace gas fluxes.