Unchanged frequency of moraine-dammed glacial lake outburst floods in the Himalaya
- Shrinking glaciers in the Hindu Kush-Karakoram-Himalaya-Nyainqentanglha (HKKHN) region have formed several thousand moraine-dammed glacial lakes(1-3), some of these having grown rapidly in past decades(3,4). This growth may promote more frequent and potentially destructive glacial lake outburst floods (GLOFs)(5-7). Testing this hypothesis, however, is confounded by incomplete databases of the few reliable, though selective, case studies. Here we present a consistent Himalayan GLOF inventory derived automatically from all available Landsat imagery since the late 1980s. We more than double the known GLOF count and identify the southern Himalayas as a hotspot region, compared to the more rarely affected Hindu Kush-Karakoram ranges. Nevertheless, the average annual frequency of 1.3 GLOFs has no credible posterior trend despite reported increases in glacial lake areas in most of the HKKHN3,8, so that GLOF activity per unit lake area has decreased since the late 1980s. We conclude that learning more about the frequency and magnitude ofShrinking glaciers in the Hindu Kush-Karakoram-Himalaya-Nyainqentanglha (HKKHN) region have formed several thousand moraine-dammed glacial lakes(1-3), some of these having grown rapidly in past decades(3,4). This growth may promote more frequent and potentially destructive glacial lake outburst floods (GLOFs)(5-7). Testing this hypothesis, however, is confounded by incomplete databases of the few reliable, though selective, case studies. Here we present a consistent Himalayan GLOF inventory derived automatically from all available Landsat imagery since the late 1980s. We more than double the known GLOF count and identify the southern Himalayas as a hotspot region, compared to the more rarely affected Hindu Kush-Karakoram ranges. Nevertheless, the average annual frequency of 1.3 GLOFs has no credible posterior trend despite reported increases in glacial lake areas in most of the HKKHN3,8, so that GLOF activity per unit lake area has decreased since the late 1980s. We conclude that learning more about the frequency and magnitude of outburst triggers, rather than focusing solely on rapidly growing glacial lakes, might improve the appraisal of GLOF hazards.…
Author details: | Georg VehORCiDGND, Oliver KorupORCiDGND, Sebastian von SpechtORCiDGND, Sigrid RößnerGND, Ariane WalzORCiDGND |
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DOI: | https://doi.org/10.1038/s41558-019-0437-5 |
ISSN: | 1758-678X |
ISSN: | 1758-6798 |
Title of parent work (English): | Nature climate change |
Publisher: | Nature Publ. Group |
Place of publishing: | London |
Publication type: | Article |
Language: | English |
Date of first publication: | 2019/03/18 |
Publication year: | 2019 |
Release date: | 2021/02/25 |
Tag: | Climate change; Cryospheric science; Environmental impact; Geomorphology |
Volume: | 9 |
Issue: | 5 |
Number of pages: | 7 |
First page: | 379 |
Last Page: | 383 |
Funding institution: | Deutsche Forschungsgemeinschaft within the graduate research training group NatRiskChange at the University of Potsdam [GRK 2043/1]; United States Department of EnergyUnited States Department of Energy (DOE) [DE-AC05-00OR22725] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
DDC classification: | 5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften |
Peer review: | Referiert |