Reconstruction of the 1941 GLOF process chain at Lake Palcacocha (Cordillera Blanca, Peru)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F86652079%3A_____%2F20%3A00523907" target="_blank" >RIV/86652079:_____/20:00523907 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.hydrol-earth-syst-sci.net/24/93/2020/" target="_blank" >https://www.hydrol-earth-syst-sci.net/24/93/2020/</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5194/hess-24-93-2020" target="_blank" >10.5194/hess-24-93-2020</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Reconstruction of the 1941 GLOF process chain at Lake Palcacocha (Cordillera Blanca, Peru)

Popis výsledku v původním jazyce

The Cordillera Blanca in Peru has been the scene of rapid deglaciation for many decades. One of numerous lakes formed in the front of the retreating glaciers is the moraine-dammed Lake Palcacocha, which drained suddenly due to an unknown cause in 1941. The resulting Glacial Lake Outburst Flood (GLOF) led to dam failure and complete drainage of Lake Jircacocha downstream, and to major destruction and thousands of fatalities in the city of Huaraz at a distance of 23 km. We chose an integrated approach to revisit the 1941 event in terms of topographic reconstruction and numerical back-calculation with the GIS-based open-source mass flow/process chain simulation framework r.avaflow, which builds on an enhanced version of the Pudasaini (2012) two-phase flow model. Thereby we consider four scenarios: (A) and (AX) breach of the moraine dam of Lake Palcacocha due to retrogressive erosion, assuming two different fluid characteristics, (B) failure of the moraine dam caused by the impact of a landslide on the lake, and (C) geomechanical failure and collapse of the moraine dam. The simulations largely yield empirically adequate results with physically plausible parameters, taking the documentation of the 1941 event and previous calculations of future scenarios as reference. Most simulation scenarios indicate travel times between 36 and 70 min to reach Huaraz, accompanied with peak discharges above 10 000 m(3)s(-1). The results of the scenarios indicate that the most likely initiation mechanism would be retrogressive erosion, possibly triggered by a minor impact wave and/or facilitated by a weak stability condition of the moraine dam. However, the involvement of Lake Jircacocha disguises part of the signal of process initiation farther downstream. Predictive simulations of possible future events have to be based on a larger set of back-calculated GLOF process chains, taking into account the expected parameter uncertainties and appropriate strategies to deal with critical threshold effects.

Název v anglickém jazyce

Reconstruction of the 1941 GLOF process chain at Lake Palcacocha (Cordillera Blanca, Peru)

Popis výsledku anglicky

The Cordillera Blanca in Peru has been the scene of rapid deglaciation for many decades. One of numerous lakes formed in the front of the retreating glaciers is the moraine-dammed Lake Palcacocha, which drained suddenly due to an unknown cause in 1941. The resulting Glacial Lake Outburst Flood (GLOF) led to dam failure and complete drainage of Lake Jircacocha downstream, and to major destruction and thousands of fatalities in the city of Huaraz at a distance of 23 km. We chose an integrated approach to revisit the 1941 event in terms of topographic reconstruction and numerical back-calculation with the GIS-based open-source mass flow/process chain simulation framework r.avaflow, which builds on an enhanced version of the Pudasaini (2012) two-phase flow model. Thereby we consider four scenarios: (A) and (AX) breach of the moraine dam of Lake Palcacocha due to retrogressive erosion, assuming two different fluid characteristics, (B) failure of the moraine dam caused by the impact of a landslide on the lake, and (C) geomechanical failure and collapse of the moraine dam. The simulations largely yield empirically adequate results with physically plausible parameters, taking the documentation of the 1941 event and previous calculations of future scenarios as reference. Most simulation scenarios indicate travel times between 36 and 70 min to reach Huaraz, accompanied with peak discharges above 10 000 m(3)s(-1). The results of the scenarios indicate that the most likely initiation mechanism would be retrogressive erosion, possibly triggered by a minor impact wave and/or facilitated by a weak stability condition of the moraine dam. However, the involvement of Lake Jircacocha disguises part of the signal of process initiation farther downstream. Predictive simulations of possible future events have to be based on a larger set of back-calculated GLOF process chains, taking into account the expected parameter uncertainties and appropriate strategies to deal with critical threshold effects.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10503 - Water resources

Projekt

<a href="/cs/project/LO1415" target="_blank" >LO1415: CzechGlobe 2020 - Rozvoj Centra pro studium dopadů globální změny klimatu</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Hydrology and Earth System Sciences

ISSN

1027-5606

e-ISSN

—

Svazek periodika

24

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

22

Strana od-do

93-114

Kód UT WoS článku

000506835900001

EID výsledku v databázi Scopus

2-s2.0-85077822472