Identification

Title

Role of elevation feedbacks and ice sheet-climate interactions on future Greenland ice sheet melt

Abstract

The Greenland ice sheet (GrIS) stores freshwater equal to more than 7â€‰m of potential sea level rise (SLR) and strongly interacts with the Arctic, North Atlantic and global climate. Over the last few decades, the ice sheet has been losing mass at a rate that is projected to increase. Interactions between the GrIS and the climate have the potential to amplify or reduce GrIS mass balance responses to ongoing and projected warming. Here, we investigate the impact of ice sheetâ€“climate interactions on the climate and mass balance of the GrIS using the Community Ice Sheet Model version 2 (CISM2) coupled with the Community Earth System Model version 2 (CESM2). To this end, we compare two idealized multi-century simulations with a non-evolving and evolving ice sheet topography in which we apply an annual 1â€‰% increase in CO2 concentrations, starting from pre-industrial (PI) until stabilization at 4Ã—PI CO2 concentrations (4Ã—CO2). By comparing the one- and two-way coupled simulations, we find significant changes in atmospheric blocking, precipitation and cloud formation over Greenland as the GrIS topography evolves, acting as negative feedbacks on mass loss. We also attribute part of the overestimation of mass loss in the one-way coupled simulation to an overestimation of melt in the ablation area caused by the use of a uniform temperature lapse rate to reflect the elevation differences between the atmospheric and ice sheet grids. Furthermore, we investigate ice sheetâ€“climate interactions in a simulation branched in year 350 from our two-way coupled simulation in which we annually reduce atmospheric CO2 by 5â€‰% until PI concentrations are reached. During the 350-year 4Ã—CO2 forcing period, the ice sheet loses a total mass of 1.1â€‰m sea level equivalent, and part of its margins retreat landward. When the PI CO2 concentration is restored, melt decreases rapidly, leading to a small positive surface mass balance. Combined with the strongly reduced ice discharge resulting from the widespread retreat of the ice sheet margin, this halts GrIS mass loss despite a remaining global warming of 2â€‰K. The GrIS, Arctic and North Atlantic strongly interact, causing a complex transitional phase towards a colder climate during the century following the CO2 reduction. Elevated atmospheric temperatures, larger ocean heat transport and deteriorated state of the snowpack, compared to the initial pre-industrial state, result in limited regrowth of the ice sheet under reintroduced PI CO2 conditions.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.net/ark:/85065/d7cr5ztc

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2025-06-27T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

<span style="font-family:Arial;font-size:10pt;font-style:normal;" data-sheets-root="1">Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.</span>

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact