Biogeosciences 7, 979–1005 (2010)

As the planet continues to warm, biological productivity in the world's oceans — the generation of organic compounds, mainly through photosynthesis, that supports life and influences Earth's climate system — looks set to fall. Researchers estimate that, by 2100, it could have decreased by as much as 20% relative to pre-industrial times.

Marco Steinacher at the University of Bern and his colleagues used four global coupled carbon-cycle–climate models to project twenty-first-century changes in net marine primary productivity in response to anthropogenic climate change. Assuming a high greenhouse-gas emissions scenario, they found that reduced ocean mixing and circulation led to decreased nutrient availability in the low- and mid-latitude oceans and in the North Atlantic. For parts of the Southern Ocean, where increased sunlight and temperatures could enhance productivity, the study projected a slight increase.