EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Observed early-warning signals for a Greenland-ice-sheet tipping point

Martin Rypdal1 and Niklas Boers2,3,4
Martin Rypdal and Niklas Boers
  • 1UiT The Arctic University of Norway, Department of Mathematics and Statistics, Tromsø, Norway (
  • 2Free University Berlin, Department of Mathematics, Berlin, Germany (
  • 3Potsdam Institute of Climate Impact Research, Potsdam, Germany
  • 4University of Exeter, Department of Mathematics and Global Systems Institute, Exeter, UK

Nonlinear feedbacks, such as the melt-elevation feedback, may produce a critical temperature threshold beyond which the current state of the Greenland Ice Sheet loses stability. Hence, the ice sheet may exhibit an abrupt transition under ongoing global warming, with substantial impacts on global sea level and the Atlantic Meridional Overturning Circulation. Melting rates across Greenland and solid ice discharge at the ice sheet's margins have recently accelerated. In this work, we analyze ice sheet runoff reconstructions and process-based simulations using new methods. We compare the acceleration in the runoff with the statistical properties of fluctuations around the system's equilibrium. The analysis uncovers significant early-warning signals for an ongoing destabilization and substantial further mass loss in the near future. 


How to cite: Rypdal, M. and Boers, N.: Observed early-warning signals for a Greenland-ice-sheet tipping point , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7369,, 2020