Journal cover Journal topic
Hydrology and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 4.936 IF 4.936
  • IF 5-year value: 5.615 IF 5-year
  • CiteScore value: 4.94 CiteScore
  • SNIP value: 1.612 SNIP 1.612
  • IPP value: 4.70 IPP 4.70
  • SJR value: 2.134 SJR 2.134
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 107 Scimago H
    index 107
  • h5-index value: 63 h5-index 63
Discussion papers
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Submitted as: research article 19 Aug 2019

Submitted as: research article | 19 Aug 2019

Review status
This discussion paper is a preprint. A revision of the manuscript is under review for the journal Hydrology and Earth System Sciences (HESS).

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

Martin Mergili1,2, Shiva P. Pudasaini3, Adam Emmer4, Jan-Thomas Fischer5, Alejo Cochachin6, and Holger Frey7 Martin Mergili et al.
  • 1Institute of Applied Geology, University of Natural Resources and Life Sciences (BOKU), Peter-Jordan-Straße 82, 1190 Vienna, Austria
  • 2Geomorphological Systems and Risk Research, Department of Geography and Regional Research, University of Vienna, Universitätsstraße 7, 1010 Vienna, Austria
  • 3Geophysics Section, Institute of Geosciences and Meteorology, University of Bonn, Meckenheimer Allee 176, 53115 Bonn, Germany
  • 4Department of the Human Dimensions of Global Change, Global Change Research Institute, The Czech Academy of Sciences, Bělidla 986/4a, 603 00, Brno, Czech Republic
  • 5Department of Natural Hazards, Austrian Research Centre for Forests (BFW), Rennweg 1, 6020 Innsbruck, Austria
  • 6Unidad de Glaciología y Recursos Hídricos, Autoridad Nacional del Agua, Confraternidad Internacional 167, Huaráz, Perú
  • 7Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland

Abstract. The Cordillera Blanca in Perú 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 Huaráz at a distance of 23 km. Lake Palcacocha has dramatically regrown through further glacial retreat since then and nowadays is again considered a threat to the downstream communities. Previously, various types of computer simulations were carried out in order to quantify the possible impact of future GLOFs from Lake Palcacocha, but no attempts are made yet to back-calculate the 1941 event. Here, 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. 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 onto 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. 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.

Martin Mergili et al.
Interactive discussion
Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Martin Mergili et al.
Martin Mergili et al.
Total article views: 474 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
373 96 5 474 8 4
  • HTML: 373
  • PDF: 96
  • XML: 5
  • Total: 474
  • BibTeX: 8
  • EndNote: 4
Views and downloads (calculated since 19 Aug 2019)
Cumulative views and downloads (calculated since 19 Aug 2019)
Viewed (geographical distribution)  
Total article views: 323 (including HTML, PDF, and XML) Thereof 314 with geography defined and 9 with unknown origin.
Country # Views %
  • 1
No saved metrics found.
No discussed metrics found.
Latest update: 13 Nov 2019
Publications Copernicus