Global clustering of recent glacier surges from radar backscatter data, 2017–2022

Abstract Using global Sentinel-1 radar backscatter data, we systematically map the locations of glaciers with surge-type activity during 2017–22. Patterns of pronounced increases or decreases in the strongest backscatter between two winter seasons often indicate large changes in glacier crevassing,...

Full description

Bibliographic Details
Published in:Journal of Glaciology
Main Authors: Kääb, Andreas, Bazilova, Varvara, Leclercq, Paul Willem, Mannerfelt, Erik Schytt, Strozzi, Tazio
Other Authors: Norges Forskningsråd, European Space Agency
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2023
Subjects:
Online Access:http://dx.doi.org/10.1017/jog.2023.35
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143023000357
Description
Summary:Abstract Using global Sentinel-1 radar backscatter data, we systematically map the locations of glaciers with surge-type activity during 2017–22. Patterns of pronounced increases or decreases in the strongest backscatter between two winter seasons often indicate large changes in glacier crevassing, which we treat here as a sign of surge-type activity. Validations against velocity time series, terminus advances and crevassing found in optical satellite images confirm the robustness of this approach. We find 115 surge-type events globally between 2017 and 2022, around 100 of which on glaciers already know as surge-type. Our data reveal a pronounced spatial clustering in three regions, (i) Karakoram, Pamirs and Western Kunlun Shan (~50 surges), (ii) Svalbard (~25) and (iii) Yukon/Alaska (~9), with only a few other scattered surges elsewhere. This spatial clustering is significantly more pronounced than the overall global clustering of known surge-type glaciers. The 2017–22 clustering may point to climatic forcing of surge initiation.