Standard Presentation (15 mins) Australian Marine Sciences Association 2022

Ecological Impacts of Changing Antarctic Sea-Ice-Scapes (#37)

Klaus Meiners 1
  1. Australian Antarctic Division, Department of Climate Change, Energy, the Environment and Water, Kingston, Tasmania, Australia

Sea ice has major, though regionally- and seasonally-varying, effects on the structure and function of Antarctic marine ecosystems and Southern Ocean biogeochemical cycles. Long-term observations from the West Antarctic Peninsula have shown how a decline in sea-ice extent and duration has impacted food webs across multiple levels and affected biogeochemical processes in intricate ways, including through cascading effects and changes in community structures. Models consistently predict a significant decrease in overall Antarctic sea-ice extent, duration and volume for the end of this century. These physical changes are expected to have major ramifications across the entire Southern Ocean, including effects on ice-associated and pelagic primary production, food-web structures and carbon export. Focussing on predicted sea-ice-scape changes in the marginal ice zone, the interior pack ice zone and in fast-ice regimes, this talk will provide a first assessment of how predicted changes in Antarctic sea ice will affect Southern Ocean ecosystems at the end of the 21st century. The talk will also highlight uncertainties in these assessments, thereby identifying key knowledge gaps in Southern Ocean ice-covered ecosystem research.