Linear response of east Greenland’s tidewater glaciers to ocean/atmosphere warming

This work was funded by NERC grants NE/K015249/1 and NE/K014609/1 to PN and AS respectively and a NERC studentship to DS. Predicting the retreat of tidewater outlet glaciers forms a major obstacle to forecasting the rate of mass loss from the Greenland Ice Sheet. This reflects the challenges of mode...

Full description

Bibliographic Details
Published in:Proceedings of the National Academy of Sciences
Main Authors: Cowton, Tom, Sole, Andrew, Nienow, Peter, Slater, Donald Alexander, Christoffersen, Poul
Other Authors: University of St Andrews. School of Geography & Sustainable Development, University of St Andrews. Bell-Edwards Geographic Data Institute
Format: Article in Journal/Newspaper
Language:English
Published: 2019
Subjects:
Ice sheets
Glaciers
Climate change
Greenland
Sea-level rise
G Geography (General)
GC Oceanography
NDAS
BDC
R2C
SDG 13 - Climate Action
G1
GC
glacier
Greenland Sea
Ice Sheet
Tidewater
Online Access:http://hdl.handle.net/10023/16870
https://doi.org/10.1073/pnas.1801769115
Description
Summary:This work was funded by NERC grants NE/K015249/1 and NE/K014609/1 to PN and AS respectively and a NERC studentship to DS. Predicting the retreat of tidewater outlet glaciers forms a major obstacle to forecasting the rate of mass loss from the Greenland Ice Sheet. This reflects the challenges of modeling the highly dynamic, topographically complex, and data-poor environment of the glacier–fjord systems that link the ice sheet to the ocean. To avoid these difficulties, we investigate the extent to which tidewater glacier retreat can be explained by simple variables: air temperature, meltwater runoff, ocean temperature, and two simple parameterizations of “ocean/atmosphere” forcing based on the combined influence of runoff and ocean temperature. Over a 20-y period at 10 large tidewater outlet glaciers along the east coast of Greenland, we find that ocean/atmosphere forcing can explain up to 76% of the variability in terminus position at individual glaciers and 54% of variation in terminus position across all 10 glaciers. Our findings indicate that (i) the retreat of east Greenland’s tidewater glaciers is best explained as a product of both oceanic and atmospheric warming and (ii) despite the complexity of tidewater glacier behavior, over multiyear timescales a significant proportion of terminus position change can be explained as a simple function of this forcing. These findings thus demonstrate that simple parameterizations can play an important role in predicting the response of the ice sheet to future climate warming. Postprint Peer reviewed

Similar Items