The availability of nutrients in the surface ocean often limits primary productivity, with implications for marine food webs and the biological carbon pump. Nitrogen availability tends to limit phytoplankton productivity throughout most of the low-latitude ocean, whereas dissolved iron availability limits productivity in high-nutrient, low- chlorophyll regions, such as in the main upwelling region of the Southern Ocean and the Eastern Equatorial Pacific  . Phosphorus, silicon, other micronutrients such as zinc, and vitamins can also co-limit marine phytoplankton productivity in some ocean regions . Whereas some studies have shown coupling between climate variability and nutrient trends in specific regions, such as in the North Atlantic , North Pacific  and tropical  Oceans, very few studies have been able to detect long-term changes in ocean nutrient concentrations .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report