Cryospheric Hazards and Risk Perceptions in the Mt. Everest Region, Nepal
1

Sonam Futi Sherpa *
1

School of Sustainability, Arizona State University Tempe, AZ 85281, USA

Abstract
Multiple studies have reported potential risks posed by a rapid expansion of glacial lakes
in the Mt. Everest region of Nepal. People’s perception of such cryospheric hazards can
influence their actions, beliefs, and responses to those hazards and associated risks. This paper
analyzes local people’s perceptions of cryospheric hazards and risks using a social survey dataset
of 138 households in the Khumbu and Pharak areas of the Mt. Everest region of Nepal. A
statistical logit model of categorical household data showed a significant positive correlation
with the perceptions of cryospheric risks to their livelihood sources, mainly tourism. Local
people’s GLOF risk perceptions are also influenced by their proximity to rapidly expanding
glacial lakes and potential flood zones located in Dudhkoshi River basin. The emergency
remediation work implemented in the Imja glacial lake by the Government of Nepal in 2016 has
served as a cognitive fix, especially in the low lying settlements in Pharak. Uncertainties of
cryosphere that exist in the region can be attributed to a disconnect between how scientific
knowledge on GLOFs risks is communicated to the local communities and how government
policies on climate change adaptation and mitigation have been limited only to awareness
campaigns and emergency remediation works. A sustainable partnership of scientists,
policymakers, and local communities is urgently needed to build a science-driven, communitybased initiative that focuses not just in addressing a single GLOF threat (e.g., Imja) but develops
on a comprehensive cryospheric risk management plan and considers opportunities and
challenges of tourism in the local climate adaptation policies.

Key words: Cryospheric hazards, GLOFs, Risk perception, Adaptation, Mt. Everest region,
Nepal

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1. Introduction
Glacial lake outburst floods (GLOFs) are among the most serious cryospheric hazards for
mountain communities around the world (Huggel et al., 2002; Carey, 2010; Bolch et al., 2012;
Nie and Liu, 2013). GLOF risks have increased significantly in the recent decades with more
rapid melting of glaciers, caused in large part by climate change (Kargel et al., 2011; NRC,
2012). In the Mt. Everest region of Nepal there have been three major GLOFs since the 1970s:
Naare (1977), Dig-Tsho (1985), and Taam Pokhari (1998) along with several smaller englacial
outburst floods that are occurring more frequently in recent years (Rounce et al. 2017). Despite
the heightened sense of vulnerability to these glacial flood events and other cryospheric hazards
among locals, there have been no systematic study to assess local people’s perceptions of risk or
what Grothmann and Pratt (2005) calls “risk appraisal” of GLOFs and other cryospheric hazards
in the region. This research seeks to address two key research questions: 1) how do the local
people perceive the risk of cryospheric hazards in comparison to other natural hazards in the
region? and 2) What are the major factors that directly influence their risk perceptions? Answers
to these questions are sought through an in-depth analysis of people’s risk perceptions of GLOFs
and other natural hazards and risks captured in a socio-economic dataset generated for a large
research project funded by an NSF CNH research grant.
GLOFs pose a significant threat to society and infrastructures. Such hazards can discharge,
with little warning, massive volumes of water in a highly destructive way, catching downstream
communities off-guard and unprepared (Bajracharya et al., 2007; Mool et al., 2011; Carey et al.,
2012). The biggest GLOF in the region, however, was the 1985 outbreak of Dig Tsho in the
Bhotekoshi Valley, which discharged an estimated 6-10 million cubic meters of water and
caused severe damage worth more than three million dollars (Mool et al., 2011). Supraglacial
lakes, such as Imja Tsho or Imja Lake, have formed in the Himalayan region over the last five
decades, and are now rapidly expanding to levels likely to trigger devastating GLOF events
(Thakuri et al., 2016, Bolch et al., 2008; Bajracharya, Shrestha, & Rajbhandari, 2007) drawing
the significant attention of media and the scientific community.
Risk perception research has long been a subject of hazards and risk analysis (Tobin and
Montz 1997). Numerous climate variability studies have repeatedly shown influence of risk
perception on people’s knowledge, action, beliefs and response (Leiserowitz 2006, Etkin & Ho
2007, Patt & Schröter 2008, Fosu-Mensah et al. 2012, Halder et al. 2012). Although scientific
2

knowledgebase on GLOF hazards and risks is fairly comprehensive for Nepal, a systematic study
of risk perception to such hazards are scarce. In such conditions, understanding of risk
perceptions to cryospheric hazards is essential to stimulate adaptive actions. The socio-cognitive
Model of Private Proactive Adaptation to Climate Change (MPPACC), which was based on
decades of research on risk perception, presents perception as a key variable influencing or being
influenced by all the model’s determinants of adaptive behavior (Gorthmann and Patt, 2005).
Perceptions of the risk from hazards and impact are shaped more by direct personal experiences
than by second hand information (Clayton et al., 2015) or information on physical and
morphological changes in physical system (e.g. change in volumes of glacial lakes or retreat of
glaciers) in case of this study. This research follows the socio-cognitive framework of Private
Proactive Adaptation to Climate Change (MPPACC) by Gorthmann and Patt (2005) to
understand how people appraise risks and to examine the factors affecting risk perception, which
has a key role in influencing adaptation action and resilience.

2. Theoretical Foundations and Gaps
2.1. Overview of cryospheric hazards and vulnerability in Nepal
2

In Nepal, among 1466 glacial lakes covering a total of 64.8 km , 21 glacial lakes have been
identified as critical (potentially dangerous) based on criteria related to factors such as, the size
and rate of growth of the lake, and position in relation to moraines and associated glaciers
(Khanal et al., 2015). Among these, Imja glacial lake located in the Mt. Everest region is
considered to be of critical (Mool et al., 2001a & 2001b) to moderate risk (Rounce et al, 2016).
Studies by Somos-Valenzuela and colleagues (2014; and 2012) focused on a bathymetry survey,
a ground-penetrating radar survey, hydrodynamic modeling and remote observations of the Imja
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glacial lake showed a rapid growth in area and volume to 61.7 ± 3.7 milliion m from 35.8 ±0.7
3

million m (Sakai et al., 2007). A flood model study conducted by Somos-Valenzuela (2015)
recommended the lowering the lake at least by 3 m to minimize potential impact in the
downstream communities, but also highlighted that significant reduction of risk could be
achieved by lowering the lake by 20 m. A case study was conducted on Tsho Rolpa located in
Dolakaha-an adjacent district highlighted diversity in people’s perceptions of GLOF risks from
the lake and their response to potential hazards. In another study, Khanal et al., (2015)
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highlighted the importance of conducting a comprehensive risk assessment of socioeconomic
vulnerability to GLOFs, particularly to design appropriate risk reduction strategies in Nepal.
However, none has used a system approach to understand both the social and natural systems
associated with GLOF and other cryospheric hazards.
While studies on vulnerability and risk perception to cryospheric hazards are relatively new
and scarce for the Himalaya, the literature on the Andes is comparatively more comprehensive.
For instance, in Peru—particularly avalanches, glacial lake outburst floods and glacier
recession—has been thoroughly examined through multi-disciplinary research (Haeberli and
Whitman, 2015; Bury, 2010; Carey, 2005). An integrated assessment of the vulnerability of
cryospheric hazards conducted by Hegglin and Huggel (2008) in the Cordillera Blanca, Peru,
including both the physical-technical and the socio-economic approaches, showed a strong need
for vulnerability research integrating physical and social sciences and related theoretical
frameworks to be readily applied in practice. Similarly, study conducted in Peru, focused mainly
on Carhuaz’s Lake 513, used an integrated socio-environmental framework for glacier hazard
management. It concluded that there was an increased need for scientific communication among
locals and policymakers (Carey et al., 2012) for better adaptive capacity and resilient society.
In this study, a schematic diagram of vulnerability of social system to cryospheric hazards
and risk and response of communities is developed to show cryospheric hazards are part of the
region’s complex natural-social systems (see Fig. 1). Understanding of risk by the communities
and enhancement of preparedness to vulnerability and risk in the system can help increase the
resilience of this complex natural and social system to eliminate vulnerability (Fig. 1).

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Preparedness

Fig.1. Complex natural-social system interaction in the mountain communities

2.2. Risk perception appraisal
Within climate change science, risk perceptions of hazards and disasters are widely
recognized. This draws heavily on the long tradition of environmental perception research in
hazards geography and risk analysis (Tobin & Montz, 1997; Cutter et al., 2003; Wisner et al.,
2004). Several studies have highlighted the importance of people’s perceptions of climate
variability and adaptation, incorporating the way public understand, recognize and respond to
risks brought by changing climate based on various socio-cultural and economic aspects (Crona
et al., 2013).
Studies have shown that understanding of the accurate perception of climatic variability and
change can facilitate individuals to take effective measures to protect their livelihood against
threats from changing the environment, and help policy maker in developing diverse strategies
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(Grorthmann and Patt, 2005, Rodriguez et al., 2017). The Grothmann and Patt model explains
two perpetual processes of risk perception and perceived adaptive capacity, “risk appraisal” and
“adaptation appraisal.” This model was applied in the case of Mexico to examine the risk
perceptions on drought exclusively among farmers, primarily to analyze why individual farmers
adapt differently to risks brought by climate change (Rodriguez et al., 2017). The cognitive
process of risk appraisal affects risk perception and is instrumental in developing climate change
adaptation policy initiatives and policies because of their ability to influence how people respond
to public communication, risk and people’s behavior in face of risk (Frank et al., 2010).
Perceived probability and perceived severity of a hazard are defined as a person’s expectancy of
being exposed to threats and how harmful the consequences of the threat would be if it were to
actually occur, respectively. For example, person’s perceived probability implies individual’s
expectancy of being exposed to a glacial flood and perceived severity indicates the judgement of
harm to property and home. Adaptation appraisal, which comes after a process of risk
perception, includes two factors: i) person’s belief in his/her capacity for adaptive action or
adaptation efficacy, and ii) the person’s perceived ability to perform or carry out adaptive
responses, or perceived self-efficacy (Grothmann and Patt, 2005: 203). This model is useful in
explaining how the local people of the Mt. Everest region of Nepal appraise risk to cryospheric
hazards, which is an essential component influencing adaptive action. This study, therefore,
adapted the Grothmann and Patt (2005) model to explain risk perception of cryospheric hazards
in the Mt. Everest region, Nepal.
A comparison of cryospheric hazards with other natural hazards are made based on the
various personal experience of the environmental changes, which enhances the level of risk one
perceives (Weber, 2010). For example, personal experience with extreme events (e.g., avalanche,
glacial flooding), and whether the respondent suffered from financial and physical damage, in a
personal level as well as community level (e.g. destruction of infrastructure), can profoundly
influence person’s risk perception and affect the subsequent actions. Figure 2 shows that different
variables that influence the people’s perception of risk and how this is essential to develop the
motivation to adapt and adaptation intention. A framework (Fig 2) adapted after the model of
Grothmann and Patt (2005) model focuses only on the perception of risk appraisal in this paper.

6

Fig. 2. Process model showing cryospheric risk appraisal and various influencing factors.

3. Research Site
This research focuses on the Mt. Everest region of Nepal, mostly known as the Khumbu
and Pharak areas as shown in Fig. 3. Situated at the base of the world’s highest peak Mt. Everest
(8848 m a.s.l.) within the Sagarmatha National Park and Buffer Zone (SNPBZ), this region
covers 124,400 hectares (1148 sq. km) (DNPWC, 2006). Geographically, the region is largely
composed of the rugged terrain and gorges of the Himalayas, with steep gradients that define
both the vegetation and the settlement of people. An exceptional area with dramatic mountains,
glaciers, deep valleys and seven peaks over 7,000 m, Mt. Everest (called Chomolungma by the
locals and Sagarmatha in Nepali) is the Khumbu region’s major attraction. The region has a
monsoon-dominated climate, with 70 to 80% of the annual precipitation falling between June
and September (Wagnon et al., 2013; Salerno et al., 2015). Winter months are normally cold and
dry with few days above freezing and very little precipitation (Shea, 2015b). Dudhkoshi river is
the main river system in the region. There are several villages and settlements along this river
basin which are considered to be vulnerable to potential flood events.
The SNPBZ covers three major village development committees (VDCs): Khumjung and
Namche VDCs and the northern part of Chaurikharka VDC (these VDCs are in the process of
being merged into the proposed Pasang Lhamu Rural municipality). In the study area, there are
63 villages and settlements, which range in the elevation from Jorsalle at 2,805 m a.s.l. to
7

Gorakshep at 5170 m a.s.l. (Puschiasis, 2015). The Khumbu valley, consisted of Khumjung and
Namche VDCs, cover much of the higher altitude villages, whereas the Pharak area—mostly in
the uppder Chaurikharka VDC--is in the lower elevation areas with more diversified livelihood
sources. This covers an area of 275 sq. km to the south of the park and was declared a buffer zone
in 2002. Sherpas are the main indigenous ethnic group in this park. The Sherpa people have
practiced subsistent agriculture since they settled in the area over 400 years ago (Klatzel, 2012:
Part 1). Over the last 50 years, however, with the opening of Khumbu region to tourism in 1950s
and with the development of Lukla airport, schools, wellness facilities, and the national park, this
has become a major tourist destination. This has led to a major transformation in the livelihoods
of the Sherpas, from being experts in high mountain farming to experts in the tourism business
(Fisher, 1990). With less than 10% of the land being cultivable, and potato the only major crop
that can be grown widely, agriculture is supplemented with tourism as the significant economic
activity in the region. However, for economically marginalized households, agriculture and
animal husbandry continue to remain a significant livelihood option (DNPWC, 2007). Those
involved in tourism businesses are often still partially involved in agriculture as a seasonal
practice.

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Fig.3. Study site.

4. Research Design
4.1 Data collection
This research draws upon the socio-economic dataset generated for a large research
project conducted in this region in which this author participated, mainly the 138 household
survey data and two focus groups discussions following the protocols of established
ethnographic methods. Since there are no comprehensive social data available in the region to
analyze people’s perceptions of natural hazards and disasters, this dataset was generated with a
mixed social scientific method, which combines a household social survey with ethnographic
techniques to generate both quantitative and qualitative understanding (Bernerd, 2006). The data
collection was completed by a team of researchers from Arizona State University, USA and

9

students from Tribhuvan University, Nepal in Summer (May-June) of 2016 and June of 2017
following the institutional review board (IRB) human subject protocol. The household survey
used a stratified random sampling method to select 150 sample households from nine villages
spread across both the Khumbu and Pharak; 138 respondents completed the survey conducted in
2016. The survey instrument elicited self-reported data on household demography, income and
livelihood sources, and people’s perceptions of climate change, glaciers, experience on climate
hazards experienced in last 10 years and an open question about natural hazards experienced in
the region by Sherpas.
To develop a comprehensive risk index, the perception of probability and severity risk
data of climate hazards were also collected from a sample size of 18 in 2017 as a pilot study.
Twenty-four in-depth-semi structured interviews were conducted in the major settlements that
are located near flood-prone areas to obtain a cognitive apprehension of risk. In this process, a
chain referral or network sampling method (snowball technique) is used where you use key
informants and or/ documents locate one or two people in the population and then ask those
people to list others in the population and recommend someone for an interview (Bernerd, 2006).
Here semi-structured interviews are not entirely used for analysis, but are used to understand the
background information of the natural-social systems of cryospheric hazards.
To get more in-depth insight as well as to compliment and cross-verify individual
responses, this study also made use of two focus group discussions were conducted in with 12
participants Dingboche (4350 m a.s.l.) village in Khumbu area and 11 participants in Monjo
(2835 m a.s.l) village in Pharak area. These two locations were purposely selected to incorporate
the thoughts and perception of residents from both Khumbu and Pharak valleys (Fig.3.). These
focus group discussions mainly concentrated on the pairwise ranking of various hazards that
were identified in the household survey to validate the information obtained from the household
survey.
4.2 Data analysis
Survey data were prepared and analyzed in the Statistical Package for the Social
Sciences (SPSS) and statistics and data (STATA) software. The key parameters obtained from
household surveys were encoded in SPSS in the form of dummy variables (0=No and 1=Yes).
These were further imported and analyzed in STATA for multiple response analysis for socio-

10

demographic characteristics of the 138 respondents. The major variables are age, gender, income
(farming or tourism) and risk experiences. First, the percent of people experiencing climate
hazards (e.g., drought, glacial floods, heavy rain, blizzards, and hailstorm) in the past 10 years
was analyzed and compared, as a proxy for personal risk experience appraisal that motivates
people to take certain action including adaptive action (Weinstein, 1989, Grothmann and Patt,
2005). An open question was asked to locals to rank different natural hazards that they have
experienced locally helped categorize and analyze these based on multiple response ranking. The
answers to this question helped us understand the relative significance of cryospheric hazards in
relation to other and risks that are not necessarily identified as climate risks. In-depth semistructured interviews provided insights and local contexts of the cultural and religious
background of the Sherpas and their understanding of risk and its relation to various natural
hazards. Those were also useful in analyzing local people’s risk perceptions in relation to
changes in livelihood, particularly from subsistence agriculture to tourism and their perspectives
on the changing climatic condition and flood events they have experienced.
4.1.1. Relationship between risk perceptions and social factors
This study employed a logit model utilizing variables recorded as a binary data (yes/no) to
analyze the influence of various social factors such as, age, gender, livelihood sources (e. g.
tourism, farming) and past flood experiences on the risk perceptions of cryospheric hazards.
Logistic regression is widely used in various studies to understand the climate change risk
perceptions (Sun and Han, 2018; Rodriguez et al., 2017). The perception on “glacial lake as
threat” is taken as a dependent variable, whereas, age, livelihood sources; tourism and farming,
experience of GLOFs, and gender are taken as explanatory variables. Details of variables and
their meanings based on household survey are presented in the Table 2. A simple logit model for
binary data is shown in following equation (i). Here 𝑦"∗ designates the latent perception on glacial
lake as threat or not.
𝑦 ∗ = 𝛼 + 𝛽𝑋" + 𝜀" ………………………………………(i)
1 𝑖𝑓 𝑦"∗ > 𝑡
𝑦" =
0 𝑖𝑓 𝑦"∗ > 𝑡
where, t is the threshold and 𝜀 denotes the error term.

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4.1.2. Ratio scale prioritization of natural hazards from focus groups
Two focus groups conducted in Dingboche (4350 m a.s.l.) in the Khumbu and one in
Monjo (2835 m a.s.l) in Pharak, generated the pairwise ranking of the various natural hazards in
the Mt. Everest region of Nepal. These pairwise ranking data of major hazard and risk categories
obtained from the focus group discussion was analyzed using ratio scale prioritization method of
Analytical Hierarchy Process (AHP) (Saaty, 1980, Zahedi, 1986). The result obtained from AHP
focus group discussion is cross-validated with the results of the household survey as a part of
data triangulation in this study.
In this method, various natural hazards were given values based on their probability and
severity as shown in Table 1. This method generated ratio data and values for each natural
hazards, which were further normalized and ranked. These scores are interpreted based on the
scores where higher values indicate that the particular natural hazard is perceived as high risk
based on their capability of damage and frequency, as compared to others and vice versa. Here,
sum of all the normalized values is 1. This analytic hierarchy method provides a means of
decomposing the problems into a rank of sub-problems that are easily comprehended and
subjectively evaluated (Saaty, 1980).
Table 1. Scoring approach of AHP for focus group discussions conducted in two villages.

Intensity of Value
1
3
5
7
9
2, 4, 6, 8
Reciprocals
4.2.2

Interpretation
Requirement i and j are of equal value
Requirement i has a slightly higher value than j
Requirement i has a strongly higher value than j
Requirement i has a very strongly higher value than j
Requirement i has an absolutely higher value than j
These are intermediate scales between two adjacent judgements
If requirement i has a lower value than j

Mental model
During the fieldwork of 2017, this study also made use of a mental modeling tool, which

is widely used in natural resource management and hazard risk management to elicit the
perceptions and worldviews of stakeholders (Jones et al., 2011). Mental modeling can capture
the plurality of stakeholder perceptions, values and goals under changing environmental
condition. The mental model of a tourism entrepreneur from Dingboche village is included in
this research, mainly to understand how and where the cryospheric hazard lies in individual’s

12

web of livelihood and risk perceptions. This provides a basic background of the livelihood
pattern and risk perception.

5.

Results
A summary of descriptive statistics for socio-demographic characteristics including age,

gender, livelihood and perception to cryospheric factors of the 138 respondents are reported in
Table 2. In this study, 47% of the respondents were female, which might be because of the head
of the family (typically male) were the ones who came forward to respond to the survey. In the
study area, all respondents reported Sherpa language as their main language and English and
Nepali languages as secondary languages. Some of the respondents were Rais and Tamangs who
migrated from the lower hill region of Solukhumbu district. Respondents age varied from
minimum 18 to maximum 80, with a mean of age 41 and the highest percentage of respondents
were from age below 30 and above 18 (67 %), as presented in Table 2. Within the region, 79% of
the sample size were involved in farming whereas, 50 % were in tourism business. The household
survey showed among138 respondents, 48% recalled flooding events that had occurred in the
region and among the 93 % of respondents who have knowledge about glacial lakes, 45 % perceive
them as threat.
Table 2: Descriptive statistics for socio-demographic characteristics of the 138 respondents in the
empirical analysis and risk experiences.

Variables (Type)
Age (C)

Female (c)
Farming (c)
Tourism (c)
Glacial Flooding event
remembers (c)
Glacial lake poses a
threat? (c)
Has any idea about glacial
lake? (c)

Definition
Age of the respondent
Share of age (%)
Age <18=<30= 67.21
Age <30=<60 = 27.87
Age <60=<80= 4.92
Female participants in the survey.
Participants involved in farming
Participants involved in tourism
Participants who remembers
GLOF event
Perception on glacial lake as a
threat
Information on glacial lake

Mean
41.00
(Min=18,
Max=80,
Median=39)

SD
14.39

Percentage (%)
47
79
50
48

-

45

-

93

-

Type: C=continuous; c=categorical.
SD= Standard Deviation

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5.1. Understanding risk perception from household survey data
An open question asked on various natural hazards allowed the locals to rank natural
hazards based on their likelihood and potential to damage. In this survey, highest portion of
people, 27 %, ranked earthquake as a most hazardous and risky as shown in Fig. 4. Since the
survey was conducted a year after the Gorkha Earthquake of Nepal in April 2015 (7.4
magnitude) most respondents ranked earthquake as most hazardous, as recent or common events
are more cognitively available. This multiple response ranking also showed 23% of respondents
perceived glacial flood as a critical hazard in the region. Blizzards, drought, and landslide are
perceived as hazardous by 11%, 9%, and 5% of the respondents respectively, whereas,
hailstorms and the lack of timely snow are perceived as hazardous by 4% of respondents each,
followed by excess or erratic rainfall by 3% respondents and less than 1% respondents identified
other different hazard categories. A comparison of cryospheric hazards with other natural
hazards allowed the study to better understand where the cryospheric hazard lies in people’s
cognition.

Fig.4. Percentages of the perceived natural hazardous event in the Everest region of overall respondents
(n=138) based on multiple response ranking.

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Since experience of risk influences people’s perception and ultimately changes people’s
behavior and motivation, this study tried to understand the percentage of people who have
experienced various climate hazards. Response of experiences of climate hazards in the last ten
years obtained from the household survey showed that the highest number of respondents (31%)
have responded experiencing blizzard in the Everest region of Nepal. 28% of the respondent
have mentioned glacial flooding, and 27% cited droughts as climate hazard experienced in last
ten years as shown in table 3. Torrential rains and hailstorm were cited by 21% and 8% of
respondents respectively.
Table 3. Percentage response on climate hazards in last 10 years.

Climate Events experiences in last 10 Years.
Yes (%)

No (%)

Drought experience
Glacial Flooding experience
Heavy rain experience

27
28
21

73
72
79

Blizzard experience
Hailstorm experience

31
8.2

69
91.8

5.2. Risk perception and influencing factors
A simple binary logit model used on categorical variables showed a significant positive
correlation between who have experienced GLOFs with perceiving glacial lakes as threat. A
negative correlation is observed with age and perception of glacial lake as a threat, indicating
older generation do not perceive glacial lakes as threat. Furthermore, a significant negative
correlation between people involved in farming and female population with perception on glacial
lake as threat showed that people of these two categories do not perceive glacial lake as threat
(Table 4). However, population involved in tourism seem to perceive glacial lake as threat as
shown in Table 4.

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Table 4. Estimates in a logit model with dependent variables: perception on glacial lake as threat with
different independent variables, age, livelihood: farming and tourism, gender and people who have
experienced GLOFs as explanatory variables.

Explanatory Variables

Model 1

Age
Involved in farming

Coefficient
-0.03*
-0.90*

Std. Err.
0.01
0.53

Involved in tourism
Gender (female)
Experienced of GLOFs

0.74*
-0.65*
0.86*

0.42
0.38
0.43

Note: * means that the corresponding parameters is different from zero at the 5% significance level.

5.4. Risk perception based on settlements
To further disaggregate the findings of household survey data, this study relied on focus
group discussion for a cross validation, which would compare the results Khumbu and Pharak
areas located in two different altitudinal zones. The pairwise ranking data from the focus group
discussion two villages, which are at a higher elevation and lower elevation, Dingboche (4350 m
a.s.l.) and Monjo (2835 m a.s.l.) villages, facilitated to better understand the perception of risk
appraisal based on location. In both settlements, the earthquake is ranked at number one, which
aligns with the outcome of household survey data obtained in 2016. However, they differed on
the second most critical hazards in their area. The GLOF was ranked in the second position in
Dingboche village (Khumbu valley), whereas unseasonable rainfall was ranked in second in the
Monjo village, which is located in lower altitude Pharak valley (see Fig. 5). In Monjo, GLOF
was ranked in 5th place as opposed to Dingboche based on the likelihood and severity of
damage.

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Fig. 5. Ranking of various natural hazards using pairwise ranking data obtained from focus group
discussion for Dingboche (red) and Monjo (blue) settlement. An Analytical Hierarchy process of
scoring is used in this data. 1-5 ranking in both settlements are shown in the figure.

5.5. Individual perception of risk and social background
A mental model (Jones et al., 2011) of one of the locals from the study site illustrates the
perceptions and worldviews of sample respondents, toward the changing cryospheric system and
changing scenarios of climate. This mental model of the tourism entrepreneur (Fig.6.) shows that
the livelihood (tourism) of people are highly impacted by any change in the climate such as,bad
weather, increasing flash floods and more importantly disappearance of the drinking water
source due to melting of the glaciers (tracks colored in orange color in the mental model in
Fig.6). Changes in the cryosphere system such as, the retreat of glaciers, Khumbu, Imja Tse,
Lhotse glacier, are observed with the formation of the small supraglacial lakes (Fig.6.). This
mental model provided a background on different components are affecting tourism—one of the
two key livelihood sources.

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Fig.6. Mental model of a tourist entrepreneur from Mt. Everest region.

6.

Discussion and Conclusion
Analyzing the perceptions of hazards and risks is increasingly being recognized in climate

change literature as an effective tool to understand how local risk perceptions can influence their
adaptation and mitigation measures. This type of study is particularly important for mountain
regions facing the impacts of climate change, where empirical studies on these topics are rare,
but could of enormous value to understand local adaptation strategies and processes. In this
study, local people’s risk perceptions of GLOF and other cryospheric hazards were
comprehensively captured and analyzed for the Mt. Everest region of Nepal. The results of this
study provide insights on how a complex set of socio-economic, cultural, and ecological factors
influence local people’s perceptions and how those could help climate adaptation and mitigation
policies in the region and the Himalayan region.
The household survey and focus groups discussion results clearly showed that local people
consistently ranked “rapid on-set” hazards with potentially catastrophic impacts such as,
earthquake, much higher than any other hazards alongside with glacial floods. The earthquake
being ranked the first place in all instances suggests that its catastrophic impacts in the 2015

18

earthquake was still fresh in local’s memories and have influenced the way people perceive the
hazard risks. This is consistent with the finding of Tversky and Kahneman (1974) that human
cognition of hazard is influenced by recent or common events that are more cognitively
available. On the other hand, although ranked much lower (Table 3), “slow on-set” climate
change impacts (Matias, 2017), such as loss of water sources (dryness) and frequent change in
the weather are two major factors that are influencing the livelihood of people besides the
changes in the cryospheric system and experience of various climate events (Table 3). This
shows the tendency among the local people to be more fearful of “rapid on-set risks” (or dread
risks) that are infrequent but are deadly in impacts. GLOF is one of those two most critical
hazards among 11 different natural hazards identified in the region.
There were, however, variations in how different individuals and communities perceive those
hazards and risks. Local perceptions of cryospheric hazard are found to be influenced
significantly by sources of livelihood, age factors, prior experiences of hazardous events, and
geography. The socioeconomic data using a logit model showed that the young people perceive
glacial lakes as a major threat than the older generation. This correlation might be due to the fact
that the younger generation has more exposure to the media and various sources of information
about changes in the glacial system brought about by climate change. In addition to this, the
outcome of the study is also comparable to study that showed a lower concern among older
people on the climate change and its adverse consequences because of shorter personal
horizon compare to the younger generation (Hamilton, 2011). Livelihoods, specifically tourism,
has a significant influence on the risk perceptions to cryospheric hazards, as it is currently the
major source of income. The ranking order obtained in both villages, Dingboche (Earthquake,
GLOF, Wind) and Monjo (earthquake, unseasonal rainfall, drought) showed a variation in the
ways these two communities located in different altitude and socio-ecologcal settings perceive
natural hazards and risks. It is important to note here that Dingboche is still a temporary and new
settlement, which once was a pasture before tourism started to grow in the 1970s to and it only
become a major stop for those tourists traveling to the Everest Base Camps and other trekking
peaks. In contrast, Monjo is a permanent settlement in Pharak areas, where farming is equally
important as tourism, the cyrospheric risk is perceived differently. This link with the significant
relationship that was observed between the people involved in tourism and perceiving glacial
lake as a threat. This adds livelihood diversification and geographic variations—two important

19

features of mountains--as an important contributing factor for the Gorthmann and Patt model
described earlier.
Another important factor that influenced people’s perceptions was whether or not the
individuals and communities had prior experiences with particular hazards. There is a direct
correlation of the experiences of GLOFs (28% population) to risk perceptions of the glacial lake
as a threat. It supports the outcome of previous studies showing the direct influence of risk
experiences on the perception of climate change (Dai et al., 2015; Zaalberg et al., 2009).
Furthermore, although both villages are situated in the flood-prone area, unlike Monjo village,
people in Dingboche village consider GLOF as a high risk. Since Dingboche is located just
below the Imja lake as compared to Monjo village (Fig.3), the proximity factor to Imja and other
glacial lakes seems to have played roles in determining their risk perception, which as it is
reported elsewhere that respondents who live nearby riverbank tend to fear flooding more than
those living further away (Siegrist and Gutscher 2006). However, their ranking of GLOF as a
critical risk did not change, even after the 2016 emergency remediation work, which lowered the
Imja Lake by 3.5m. However, the result was different in Monjo village when a follow-up survey
2017 (Fig. 4) showed a change in how this community ranked GLOF after the completion of the
th

project. In 2016, it was ranked third, but in 2017, it was ranked much lower (7 place). The
reason cited by the focus group participant was that the Imja Lake was already dammed by the
government and thus, the risk of flood was lower, even though some scientists believe the lake
should be lowered by 20 meters to eliminate the flood impact in the nearest village, Dingboche
(Somos et al., 2015). This change could be explained by what some call a “cognitive fix” for the
people influencing their behavior (Heberlein, 2014: 588) and ranked hazards as less threat.
The social factors influencing local people’s risk perceptions are also strongly conditioned by the
larger institutional and political factors associated with the central government’s relationships
with Sherpa communities. Of particular importance is the territorial control of the central
government through the establishment of SNPBZ and how tourist revenues are shared and
allocated in development projects; however, these are beyond the scope of this paper, and is
hoped be addressed in the larger study. This is particularly important for developing a local
adaptation plan of action that could address cryospheric hazards as part of a more comprehensive
plan for this region.

20

It was clear during the study that government level climate adaptation policies need to go
beyond providing only climate awareness, and locals should be involved in decision-making
processes to develop a resilient society and to have a sustainable risk reduction approaches. This
study hopes to provide information to climate adaptation policymakers about the current status of
the system to develop better adaptive capacity. Among other factors influencing how individual
perceive cryopsheric hazards, it is important to note how scientific and policy information
regarding those hazards is communicated to local communities. In this region, many scientific
studies have been conducted to assess the hazards and risks associated with GLOFs starting from
the early 1980s. However, there are also, contrasting scientific findings communicated to the
locals. The Imja glacial lake, for instance, was categorized as a potentially dangerous glacial lake
(Ives and Messerili 1981; Vuichard and Zimmerman 1987; Hammond et al., 1988) in the 1980s,
but some scientists found this be one of the most dangerous glacial lakes (Yamada and Sharma
1993; Watanabe 1994; Watanabe 1995); however, some other found the lake to be moderate to
of no risk (Byers et al., 2013; Somos et al., 2014; Thakuri et al., 2016; Rounce et al., 2016).
Although uncertainty is a reality in scientific studies, different scientific projects and confusions
about the risk of Imja glacial lake have resulted in more confusions among the local people.
Despite several years of effort, knowledge exchange and science communication by the experts
and government agencies to the Sherpas of the Khumbu and Pharak valleys have been fruitful,
and in turn, has increased a sense of fear and dread among them. In addition to this, the small
englacial flood happened in June immediately after the earthquake of April 2015 created more
fear and panic not only among the people in Khumbu and Pharak area but also the people living
in along the riversides of Dudhkoshi Valley. Therefore, a sustainable partnership of scientists,
policymakers, and local communities is urgently needed to build a science-driven, communitybased initiative that focuses not just in addressing a single GLOF threat (e.g., Imja) but develops
on a comprehensive cryospheric risk management plan and considers opportunities and
challenges of tourism in the local climate adaptation policies

Acknowledgements
This material is based upon work supported by the National Science Foundation under
the grant number CNH-1516912, CNH-L: Science-Driven, Community-Based Approach to
Reducing Glacier Lake Outburst Flood Risks, which is a collaborative research project of
21

University of Texas, Austin (PI: Dr. Deane McKinney), Arizona State University (Co-PI: Dr.
Milan Shrestha), and University of Colorado, Boulder (Co-PI: Dr. Alton Byers). Their guidance
and support is gratefully acknowledged. Summer fieldwork of 2016 immensely benefitted from
the research assistance received from Mr. Jagadish Parajuli (ASU, School of Sustainability) and
Mr. Saroj Adhikary, Ms. Shanta Sharma, and Mr. Lalmani Wagle of Tribhuvan University,
Nepal.

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