The state of rock debris covering Earth’s glaciers

Sam Herreid*, Francesca Pellicciotti

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)
2 Downloads (Pure)

Abstract

Rock debris can accumulate on glacier surfaces and dramatically reduce glacier melt. The structure of a debris cover is unique to each glacier and sensitive to climate. Despite this, debris cover has been omitted from global glacier models and forecasts of their response to a changing climate. Fundamental to resolving these omissions is a global map of debris cover and an estimate of its future spatial evolution. Here we use Landsat imagery and a detailed correction to the Randolph Glacier Inventory to show that 7.3% of mountain glacier area is debris covered and over half of Earth’s debris is concentrated in three regions: Alaska (38.6% of total debris-covered area), Southwest Asia (12.6%) and Greenland (12.0%). We use a set of new metrics, which include stage, the current position of a glacier on its trajectory towards reaching its spatial carrying capacity of debris cover, to quantify the state of glaciers. Debris cover is present on 44% of Earth’s glaciers and prominent (>1.0 km2) on 15%. Of Earth’s glaciers, 20% have a substantial percentage of debris cover for which the net stage is 36% and the bulk of individual glaciers have evolved beyond an optimal moraine configuration favourable for debris-cover expansion. Use of this dataset in global-scale models will enable improved estimates of melt over 10.6% of the global glacier domain.

Original languageEnglish
Pages (from-to)621-627
Number of pages7
JournalNature Geoscience
Volume13
Issue number9
Early online date3 Aug 2020
DOIs
Publication statusPublished - 1 Sep 2020

Fingerprint Dive into the research topics of 'The state of rock debris covering Earth’s glaciers'. Together they form a unique fingerprint.

Cite this