Feedbacks between the Greenland and Antarctic ICE sheets via the Meridional Overturning Circulation and relative sea-level (ICE-MOC)

• Applicant: Dr. Torsten Albrecht
• Subject Area: Oceanography
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 522416770

Sea-level rise poses a future challenge for coastal regions worldwide. Uncertainties in projecting future sea-level rise are strongly dominated by the potential contribution of the ice sheets covering Greenland and Antarctica. Both ice sheets display critical threshold behavior, which means accelerated and irreversible ice loss when associated feedback mechanisms (e.g. the melt-elevation feedback and the marine ice sheet instability) become self-amplifying after crossing certain temperature regimes. Also, the thermohaline meridional ocean circulation, connecting the ice sheets, has shown abrupt changes between multistable modes in the past. They are therefore considered as tipping elements of the climate system, which may interact across the globe in terms of tipping cascades. In our project, we want to gain a better understanding of the involved feedbacks and potential teleconnections between the Greenland and the Antarctic Ice Sheet via changes in relative sea level and changes in water and energy transport of the ocean. Therefore, we will use a coupled ice sheet - ocean - sea-level model to run simulations for a warmer future climate over 1000 years, to investigate critical threshold and implied rates of change, but also the potential global consequences by rising sea-level and changing ocean currents. The main focus of our project is on an improved process and system understanding between ice, ocean and solid Earth components, which we will consider for individual interfaces, regions and time scales.

• DFG Programme: Infrastructure Priority Programmes
• Subproject of: SPP 1158: Infrastructure area - Antarctic Research with Comparative Investigations in Arctic Sea Ice Areas
• Co-Investigator: Professorin Dr. Ricarda Winkelmann