Use of multi-criteria decision analysis to identify potentially dangerous glacial lakes

Abstract

Glacial Lake Outburst Floods (GLOFs) represent a significant threat in deglaciating environments, necessitating the development of GLOF hazard and risk assessment procedures. Here, we outline a Multi-Criteria Decision Analysis (MCDA) approach that can be used to rapidly identify potentially dangerous lakes in regions without existing tailored GLOF risk assessments, where a range of glacial lake types exist, and where field data are sparse or non-existent. Our MCDA model (1) is desk-based and uses freely and widely available data inputs and software, and (2) allows the relative risk posed by a range of glacial lake types to be assessed simultaneously within any region. A review of the factors that influence GLOF risk, combined with the strict rules of criteria selection inherent to MCDA, has allowed us to identify 13 exhaustive, non-redundant, and consistent risk criteria. We use our MCDA model to assess the risk of 16 extant glacial lakes and 6 lakes that have already generated GLOFs, and found that our results agree well with previous studies. For the first time in GLOF risk assessment, we employed sensitivity analyses to test the strength of our model results and assumptions, and to identify lakes that are sensitive to the criteria and risk thresholds used. A key benefit of the MCDA method is that sensitivity analyses are readily undertaken. Overall, these sensitivity analyses lend support to our model, although we suggest that further work is required to determine the relative importance of assessment criteria, and the thresholds that determine the level of risk for each criterion. As a case study, the tested method was then applied to 25 potentially dangerous lakes in the Bolivian Andes, where GLOF risk is poorly understood; 3 lakes are found to pose 'medium' or 'high' risk, and require further detailed investigation.

GLOFs in the WOS: bibliometrics, geographies and global trends of research on glacial lake outburst floods (Web of Science, 1979–2016)

“…Individual reviews of these selected aspects of GLOF research have been elaborated, e.g. by Huggel et al (2002) and Quincey et al (2005), focusing on the application of remotely sensed data, and by Kougkoulos et al (2018), focusing on GLOF susceptibility assessment (see also Sect. 4.3).…”

“…3.3). While hazard (susceptibility) assessment is traditionally dominant in GLOF risk studies (see the overview of methods by Kougkoulos et al, 2018), vulnerability assessment and adaptation in the broader context of retreating glaciers and water resources still remain brand new topics, which need to be further addressed in most regions and especially those located in developing countries (e.g. Vuille et al, 2018).…”

Modelling glacial lake outburst flood impacts in the Bolivian Andes

“…1). The three lakes identified by Kougkoulos et al (2018) as having the highest risk include Laguna Arkhata, Pelechuco Lake, and Laguna Glaciar (Fig. 1).…”

“…They undertook a rudimentary assessment of GLOF risk in the region, suggesting that 25 lakes could pose a risk to downstream communities. Subsequent work by Kougkoulos et al (2018) developed a GLOF risk assessment technique based on the use of multicriteria decision analysis (MCDA), which was applied to the lake inventory of Cook et al (2016). Kougkoulos et al (2018) found that two lakes represented 'medium' risk and one lake represented 'high' risk.…”

“…Subsequent work by Kougkoulos et al (2018) developed a GLOF risk assessment technique based on the use of multicriteria decision analysis (MCDA), which was applied to the lake inventory of Cook et al (2016). Kougkoulos et al (2018) found that two lakes represented 'medium' risk and one lake represented 'high' risk. In this study, we aim to model potential GLOF inundation downstream from these three lakes and assess the possible impacts on downstream communities and infrastructure.…”