Impacts of sea ice change on the Southern Ocean ecosystem in a warming climate

Marine ecosystems and biogeochemical cycles of the Southern Ocean play an extremely important role in the climate system. Phytoplankton growth in this area is often limited by the availability of iron and light. Recent studies have found that sea ice, as one of the most important iron sources, could significantly affect biological production and carbon export in the Southern Ocean. Sea ice also plays an important role in the Southern Ocean ecosystem by modulating photosynthetically available radiation and providing ‘seeding’ biomass in spring. Seasonality and coverage of sea ice may change significantly due to global warming. Loss of sea ice would affect phytoplankton competition, total biological production, and nutrient consumption in the area, and eventually alter the global biogeochemical cycles. The importance of sea ice on phytoplankton growth and phytoplankton composition will be investigated using coupled simulations under various climate scenarios. Potential impacts of sea ice loss on marine ecosystems and the carbon cycle in the Southern Ocean will be examined.