In the Southern Ocean, calcifying organisms are also most vulnerable to ocean acidification  , as evidenced by rates of calcification declining by 3.9% between 1998 and 2014 . Calcifying species with low- magnesium calcite or mechanisms to protect their skeletons are less vulnerable to the corrosive effects of acidification than those using aragonite or high-magnesium calcite  . In diatom-dominated communities, silicification diminishes with reduced pH levels, albeit with rates differing among taxa  . Species-specific responses exist regarding growth and primary production, which are further strongly modulated by iron and light availability  .A meta-analysis yielded different CO2 thresholds for Antarctic organismal groups; for example, negative impacts emerged at >1000 patm CO2 in phytoplankton and at >1500 patm CO2 in invertebrates, whereas bacterial abundance was positively affected by ocean acidification . Species sensitivity can also differ strongly between life-cycle stages . For instance, eggs and embryos of Antarctic krill are negatively impacted at >1250 patm CO2 whereas adults can thrive even at 1000-2000 patm CO2 over one year .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report