In:
The Cryosphere, Copernicus GmbH, Vol. 15, No. 1 ( 2021-01-14), p. 199-214
Kurzfassung:
Abstract. The lower parts of two glaciers in the Aru range on the
western Tibetan Plateau (TP) collapsed on 17 July and 21 September 2016,
respectively, causing fatal damage to local people and their livestock. The
giant ice avalanches, with a total volume of 150 × 106 m3,
had almost melted by September 2019 (about 30 % of the second ice
avalanche remained). The impact of these extreme disasters on downstream
lakes has not been investigated yet. Based on in situ observation,
bathymetry survey and satellite data, we explore the impact of the ice
avalanches on the two downstream lakes (i.e., Aru Co and Memar Co) in terms
of lake morphology, water level and water temperature in the subsequent 4 years (2016–2019). After the first glacier collapse, the ice avalanche slid
into Aru Co along with a large amount of debris, which generated great
impact waves in Aru Co and significantly modified the lake's shoreline and
underwater topography. An ice volume of at least 7.1 × 106 m3 was discharged into Aru Co, spread over the lake surface and
considerably lowered its surface temperature by 2–4 ∘C in the first 2 weeks after the first glacier collapse. Due to the large amount of meltwater
input, Memar Co exhibited more rapid expansion after the glacier collapses
(2016–2019) than before (2003–2014), in particular during the warm season.
The melting of ice avalanches was found to contribute to about 23 % of the
increase in lake storage between 2016 and 2019. Our results indicate that
the Aru glacier collapses had both short-term and long-term impacts on the
downstream lakes and provide a baseline in understanding the future lake
response to glacier melting on the TP under a warming climate.
Materialart:
Online-Ressource
ISSN:
1994-0424
DOI:
10.5194/tc-15-199-2021
DOI:
10.5194/tc-15-199-2021-supplement
Sprache:
Englisch
Verlag:
Copernicus GmbH
Publikationsdatum:
2021
ZDB Id:
2393169-3
