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Increased crevassing across accelerating Greenland Ice Sheet margins
Thomas R Chudley1,2, Ian M Howat2,3, Michalea D King4
1Department of Geography, Durham University, Durham, UK.
Nature Geoscience
|February 14, 2025
Summary
Surface crevassing on the Greenland Ice Sheet significantly increased in some areas between 2016 and 2021, linked to accelerating ice flow. This finding is crucial for understanding ice sheet mass loss and its impacts.
Area of Science:
- Glaciology
- Climate Science
- Earth Observation
Background:
- Surface crevassing is a major unknown in Greenland Ice Sheet mass loss.
- Existing data lacks comprehensive observations of crevasse location and evolution.
Purpose of the Study:
- To quantify changes in crevasse volume across the Greenland Ice Sheet between 2016 and 2021.
- To understand the relationship between ice flow dynamics and crevasse development.
Main Methods:
- Utilized high-resolution digital elevation models (DEMs) to map crevasse fields.
- Analyzed 3D crevasse volumes for the years 2016 and 2021.
- Correlated crevasse volume changes with ice discharge data.
Main Results:
- Significant increases in crevasse volume observed in marine-terminating sectors with accelerating flow (e.g., +25.3% in the southeast).
- Crevasse volume reduction noted in the central west sector (-14.2%), notably at Jakobshavn Isbræ.
- Overall ice sheet-wide change in crevasse volume was within measurement error (+4.3%).
Conclusions:
- Accelerating ice flow in Greenland drives substantial crevasse increases within five years.
- Crevasse evolution provides a mechanism for sub-decadal mass loss feedbacks.
- Findings improve understanding of calving, ice flow, and basal water transfer.
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