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Title: Increasing rate of 21st century volume loss of the Patagonian Icefields measured from proglacial river discharge
Abstract

The Northern and Southern Patagonian Icefields are rapidly losing volume, with current volume loss rates greater than 20 km3a−1. However, details of the spatial and temporal distribution of their volume loss remain uncertain. We evaluate the rate of 21st-century glacier volume loss using the hydrological balance of four glacierised Patagonian river basins. We isolate the streamflow contribution from changes in ice volume and evaluate whether the rate of volume loss has decreased, increased, or remained constant. Out of 11 glacierised sub-basins, seven exhibit significant increases in the rate of ice volume loss, with a 2006–2019 time integrated anomaly in the rate of glacier volume loss of 135 ± 50 km3. This anomaly in the rate of glacier-volume-loss is spatially heterogeneous, varying from a 7.06 ± 1.69 m a−1increase in ice loss to a 3.18 ± 1.48 m a−1decrease in ice loss. Greatest increases in the rate of ice loss are found in the early spring and late summer, suggesting a prolonging of the melt season. Our results highlight increasing, and in some cases accelerating, rates of volume loss of Patagonia's lake-terminating glaciers, with a 2006–2019 anomaly in the rate of glacier volume loss contributing an additional 0.027 ± 0.01 mm a−1of global mean sea-level rise.

 
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Award ID(s):
1759071 1714614
PAR ID:
10480388
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Cambridge University Press
Date Published:
Journal Name:
Journal of Glaciology
Volume:
69
Issue:
277
ISSN:
0022-1430
Page Range / eLocation ID:
1187 to 1202
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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