The ocean environment is projected to face increasing stress due to ocean warming, acidification, and deoxygenation in the coming decades and century. Without significant CO2 emission reductions, the goal of limiting global warming within the Paris Agreement targets - and thereby reducing marine ecosystem stress - will become increasingly difficult to attain. There remains a wide knowledge gap regarding the ocean biogeochemical impacts of crossing critical temperature thresholds or the so-called 'safe operating space'. Projected changes in both short-term extreme events and long-term ecosystem stressors (such as warming, acidification, and deoxygenation) and their reversibility could have significant societal impacts, making them highly relevant for policy-making. The long-term response of ocean carbon sources and sinks will also have broader implications for the global carbon budget and future emission pathways. This session aims to enhance our understanding of ocean biogeochemical interactions and feedback with other components of Earth system, particularly in connections to climate variations.. We invite studies utilizing modeling, observational data, historical reconstructions, and other innovative approaches to advance knowledge across a range of spatial and temporal scales. We welcome studies covering past, present, and future variability and changes in ocean biogeochemistry. Contributions addressing ocean biogeochemical responses to extreme events, climatological states, and the long-term legacy of anthropogenic climate change are particularly encouraged.

The ocean environment is projected to face increasing stress due to ocean warming, acidification, and deoxygenation in the coming decades and century. Without significant CO2 emission reductions, the goal of limiting global warming within the Paris Agreement targets - and thereby reducing marine ecosystem stress - will become increasingly difficult to attain. There remains a wide knowledge gap regarding the ocean biogeochemical impacts of crossing critical temperature thresholds or the so-called 'safe operating space'. Projected changes in both short-term extreme events and long-term ecosystem stressors (such as warming, acidification, and deoxygenation) and their reversibility could have significant societal impacts, making them highly relevant for policy-making. The long-term response of ocean carbon sources and sinks will also have broader implications for the global carbon budget and future emission pathways. This session aims to enhance our understanding of ocean biogeochemical interactions and feedback with other components of Earth system, particularly in connections to climate variations.. We invite studies utilizing modeling, observational data, historical reconstructions, and other innovative approaches to advance knowledge across a range of spatial and temporal scales. We welcome studies covering past, present, and future variability and changes in ocean biogeochemistry. Contributions addressing ocean biogeochemical responses to extreme events, climatological states, and the long-term legacy of anthropogenic climate change are particularly encouraged.