Marine primary production is projected to further decrease by 2100 in most European seas between 0.3% at 1.5°C GWL to 2.7% at 4°℃ GWL  , mainly caused by stratification- driven reductions in nutrient availability, impacting food webs . In the Barents Sea, however, largely stable primary production is projected under all scenarios in response to sea ice decline  and in the eastern Mediterranean due to reduced stratification . These changes in productivity are projected to increase fish and macroinvertebrate biomass between 5 and 22% . Decreasing net primary production will impact higher trophic levels , for example, in TEUS . Marine animal biomass is projected to likely decline in most European waters, with decreases <10% under all scenarios until the 2030s but losses growing to 25% at 2℃ GWL and 50% at 4°C GWL in coastal waters of the northeast Atlantic .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report