Preprints
https://doi.org/10.5194/esd-2021-100
https://doi.org/10.5194/esd-2021-100
 
17 Dec 2021
17 Dec 2021
Status: a revised version of this preprint is currently under review for the journal ESD.

Dynamic regimes of the Greenland Ice Sheet emerging from interacting melt-elevation and glacial isostatic adjustment feedbacks

Maria Zeitz1,2, Jan M. Haacker1,2,3, Jonathan F. Donges1,4, Torsten Albrecht1, and Ricarda Winkelmann1,2 Maria Zeitz et al.
  • 1Earth System Analysis, Potsdam Institute for Climate Impact Research, Member of the Leibniz Association, Telegrafenberg A31, 14473 Potsdam, Germany
  • 2Institute for Physics and Astronomy, University of Potsdam, Potsdam, Germany
  • 3Delft University of Technology, Faculty of Civil Engineering and Geosciences, Department of Geoscience and Remote Sensing, Delft, The Netherlands
  • 4Stockholm Resilience Centre, Stockholm University, Kräftriket 2B, 11419 Stockholm, Sweden

Abstract. The stability of the Greenland Ice Sheet under global warming is governed by a number of dynamic processes and interacting feedback mechanisms in the ice sheet, atmosphere and solid Earth. Here we study the long-term effects due to the interplay of the competing melt-elevation and glacial isostatic adjustment (GIA) feedbacks for different temperature step forcing experiments with a coupled ice-sheet and solid-Earth model. Our model results show that for warming levels above 2 °C, Greenland could become essentially ice-free on the long-term, mainly as a result of surface melting and acceleration of ice flow. These ice losses can be mitigated, however, in some cases with strong GIA feedback even promoting the partial recovery of the Greenland ice volume. We further explore the full-factorial parameter space determining the relative strengths of the two feedbacks: Our findings suggest distinct dynamic regimes of the Greenland Ice Sheets on the route to destabilization under global warming – from recovery, via quasi-periodic oscillations in ice volume to ice-sheet collapse. In the recovery regime, the initial ice loss due to warming is essentially reversed within 50,000 years and the ice volume stabilizes at 61–93 % of the present-day volume. For certain combinations of temperature increase, atmospheric lapse rate and mantle viscosity, the interaction of the GIA feedback and the melt-elevation feedback leads to self-sustained, long-term oscillations in ice-sheet volume with oscillation periods of tens to hundreds of thousands of years and oscillation amplitudes between 15–70 % of present-day ice volume. This oscillatory regime reveals a possible mode of internal climatic variability in the Earth system on time scales on the order of 100,000 years that may be excited by or synchronized with orbital forcing or interact with glacial cycles and other slow modes of variability. Our findings are not meant as scenario-based near-term projections of ice losses but rather providing insight into of the feedback loops governing the "deep future" and, thus, long-term resilience of the Greenland Ice Sheet.

Maria Zeitz et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on esd-2021-100', Kristin Poinar, 23 Feb 2022
    • AC2: 'Reply on RC1, RC2 and EC1&EC2', Maria Zeitz, 04 May 2022
  • RC2: 'Comment on esd-2021-100', Anonymous Referee #2, 06 Apr 2022
    • AC2: 'Reply on RC1, RC2 and EC1&EC2', Maria Zeitz, 04 May 2022
  • EC1: 'Comment on esd-2021-100', Michel Crucifix, 21 Apr 2022
    • AC2: 'Reply on RC1, RC2 and EC1&EC2', Maria Zeitz, 04 May 2022
  • EC2: 'Comment on esd-2021-100', Michel Crucifix, 21 Apr 2022
    • AC2: 'Reply on RC1, RC2 and EC1&EC2', Maria Zeitz, 04 May 2022

Maria Zeitz et al.

Model code and software

Parallel Ice Sheet Model (PISM) the PISM authors https://github.com/pism/pism

Maria Zeitz et al.

Viewed

Total article views: 945 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
779 146 20 945 44 10 4
  • HTML: 779
  • PDF: 146
  • XML: 20
  • Total: 945
  • Supplement: 44
  • BibTeX: 10
  • EndNote: 4
Views and downloads (calculated since 17 Dec 2021)
Cumulative views and downloads (calculated since 17 Dec 2021)

Viewed (geographical distribution)

Total article views: 886 (including HTML, PDF, and XML) Thereof 886 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 27 May 2022
Download
Short summary
The stability of the Greenland Ice Sheet under global warming is crucial. Here, using the Parallel Ice Sheet Model, we study how to the interplay of feedbacks between the ice sheet and the atmosphere and solid Earth affect the long-term response of the Greenland Ice Sheet. Our findings suggest four distinct dynamic regimes of the Greenland Ice Sheets on the route to destabilization under global warming – from recovery, via quasi-periodic oscillations in ice volume to ice-sheet collapse.
Altmetrics