Erosional dam breach modelling for multi-glacial lake outburst process and downstream flood exposure assessment in the Eastern Himalayas

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F25%3A10489270" target="_blank" >RIV/00216208:11310/25:10489270 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=..scbZS49J" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=..scbZS49J</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jhydrol.2024.132417" target="_blank" >10.1016/j.jhydrol.2024.132417</a>

Result language

angličtina

Original language name

Erosional dam breach modelling for multi-glacial lake outburst process and downstream flood exposure assessment in the Eastern Himalayas

Original language description

Accelerating global warming has led to the retreat of glaciers and the concurrent expansion of glacial lakes in the Himalayas, increasing the risk of glacial lake outburst floods (GLOFs) with potential to destroy infrastructure and lives in the downstream river valley. In the Sikkim Himalayas, the potentially hazardous Gurudongmar lake complex (GLC) consists of four lakes containing approximately 148 x 10(6) m3 of water with an enlargement rate of 74 +/- 3 %. Therefore, evaluating possible GLOF hazards from GLC under the current scenario is very important. We have presented in this paper an integrated and robust GLOF model that combines the physical moraine- dam breach using TELEMAC 2D and SISYPHE with 1-D inundation modelling using HEC-RAS for the multi-lake complex to estimate the peak flood (m3/s), flood depth (m), and flow velocity (m/sec) and finally assess the downstream inundation exposure. The present study also incorporates different breaching scenarios calculated based on remote sensing and field survey data of surrounding moraine-dam parameters of the GLC. In the largest- cases of GLOFs, with an 80 % overtopping dam breach, the flood peak would reach 5833.7, 7684.0, and 8882.0 m3/s for scenarios 1C, 4C, and 5C, respectively. These floods would release a total volume of 39.9, 48.5, and 59.4 x 10(6) m3 of water for the three scenarios, respectively. The downstream flood exposure assessment is based on different land use types and flood heights observed across nine scenarios (labelled 1A-5C) for each settlement using a 15 x 15 m fishnet method. The results for all 19 settlement sites along the main Tista River channel show a logical trend of increasing potential exposures. However, when the water volumes from GL-2 and GL-1 or GL-3 and GL-1 are combined, the risk of a potential flood rises. An increase in the potential flood depth directly results in higher exposure to infrastructure. The GLOF exposure levels for each scenario at 19 settlement sites differed. However, the Thangu Valley and Chungthang town have the highest inundation exposure due to their size and potential losses. This research article contributes to developing moraine-dam erosional breach modelling for multi-glacial lake outburst scenarios and downstream flood exposure assessment in the Hindu Kush-Karakoram- Himalayan region.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10508 - Physical geography

Project

<a href="/en/project/EH22_008%2F0004605" target="_blank" >EH22_008/0004605: Natural and anthropogenic georisks</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Hydrology

ISSN

0022-1694

e-ISSN

1879-2707

Volume of the periodical

649

Issue of the periodical within the volume

March

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

21

Pages from-to

132417

UT code for WoS article

001380516100001

EID of the result in the Scopus database

2-s2.0-85211174048