3Outline of Research Project on Glacial Lake Outburst Floods in
the Bhutan Himalayas
Koji FUJITA1*, Kouichi NISHIMURA1, Jiro KOMORI1,2, Shuji IWATA3, Jinro UKITA4,
Takeo TADONO5 and Toru KOIKE6
1

Graduate School of Environmental Studies, Nagoya University,
Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan2
Department of Modern Life, Teikyo Heisei University, Toshima-ku, Tokyo 170-8445, Japan
3
College of Tourism, Rikkyo University, Niiza-shi, Saitama 352-8558, Japan
4
Faculty of Science, Niigata University, Nishi-ku, Niigata 950-2181, Japan
5
Earth Observation Research Center, Japan Aerospace Exploration Agency, Tsukuba, Ibaraki 305-8505, Japan
6
Earth System Science Co., Ltd., Shinjuku-ku, Tokyo 160-0022, Japan*e-mail: cozy@nagoya-u.jp

Abstract
Glacial Lake Outburst Floods (GLOFs) are a major hazard of concern to mountain communities in the
Himalayas. In 2009 we started a three-year research project, in which we have conducted evaluation of GLOF
risk using satellite data, in-situ surveys, and breach and flood simulations, and have produced a hazard map ofpossible floods. We have primarily focused on the Mangde-Chhu basin, for which the GLOF hazard level has
been believed to be high but information regarding mitigation has been lacking. In this article, we describe thestructure and strategy of the research project, and major results obtained to date.
Key words: bathymetry survey, Bhutan Himalaya, glacial lake outburst flood, hazard map, technology transfer

1. Introduction
A glacial lake outburst flood (GLOF) occurs when abody of water that is contained by a glacier or terminal
moraine is released. In Himalayan countries such as
Bhutan and Nepal, hazards from GLOFs are an urgent
environmental and economical issue. Since the 1960s, anumber of GLOFs have been recorded concurrent withshrinkage of glaciers and expansion of glacial lakes over
the region. These observations have led to the notion thatrecent global warming may have resulted in an increasing
amount of GLOF risk. However, many glacial lakes
started to expand prior to the 1970s when the global average surface temperature began to increase most significantly. There is no clear indication that the rates at which
glacial lakes are expanding have recently accelerated(Fujita et al., 2009). Studies suggest a positive feedback
between the enlargement of glacial lakes and the increasing amount of calving through melting and upliftingfrom buoyant effects (Röhl, 2008; Sakai et al., 2009).
This feedback process would provide a potential explanation for the expansion of glacial lakes within thecontext of natural variability. At present, a firm link has
yet to be established between global warming and GLOF
events. Our knowledge on GLOFs, including detailed
geological and hydrological processes, is not sufficient to
Global Environmental Research
16/2012: 3-12
printed in Japan

provide a comprehensive understanding of GLOF
mechanisms (Yamada, 1998; Richardson & Reynolds,
2000).
Nonetheless, a great amount of effort has been put
into assessing GLOF risk for potentially dangerous
glacial lakes in this region. The International Centre forIntegrated Mountain Development (ICIMOD) in
Kathmandu, Nepal, reported that a total of 44 lakes in
Nepal and Bhutan pose a danger of outbursts (Mool et al.,2001a, 2001b). Although these efforts are well-spent,
uncertainties remain as to what criteria we should choose
for objectively evaluating GLOF risk. It is of our opinion
that this question can be best answered through a comprehensive assessment of topography around potentially
dangerous lakes with digital elevation data obtained fromboth satellites and field observations. Here the analysis
period must be extended as far back as possible to gain amaximum amount of information on the lakes’ history.
The analysis area must also be extended to a larger area,
assuring the validity of the study results.
An equally if not more urgent task is to find ways toprevent and adapt to the hazards of GLOFs. This can beaccomplished by first constructing a hazard map. Here
we need to consider the downstream topography of river
channels and debris flows. Each lake or river basin mustbe evaluated on an individual basis. This calls for satellite©2012 AIRIES4

K. FUJITA et al.

data as it is the only possible means to acquire topographic and geographical information on a large numberof lakes. The aim here must be towards gaining necessary
information for objectively constructing hazard maps,
optimizing warning systems, and performing drainage
work in a cost-effective manner.
Punakha in Bhutan was inundated by a GLOF in 1994
which was triggered by an outburst from the Lugge
Glacial Lake in the Lunana region, which is located 100
km upstream (Tashi, 1994). This event solidified coordination and cooperation in glacier and GLOF research
between Bhutan and Japan. Responding in part to arequest by the Bhutanese government in 1998, a teamcomposed of researchers from Nagoya University, Tokyo
Metropolitan University and the Bhutanese Departmentof Geology and Mines (DGM) made an initial assessmentof GLOF risk using field observations (Ageta et al.,
2000; Iwata et al., 2002; Yamada et al., 2004). This work
sets a precedent for studying GLOFs from both academic
and social points of view, leading to continuous cooperation between the DGM and Japanese researchers
over the years.
This present project aims essentially to elevate thelevel of cooperation between the Bhutanese and Japanesein GLOF research to yet another level and was started in2009 as one of the “Science and Technology ResearchPartnership for Sustainable Development (SATREPS)”
programs supported by Japan Science and Technology
Agency (JST) and Japan International Cooperation
Agency (JICA). The plan is comprehensive, covering all
three aspects of GLOF research, namely process studies,risk assessment, and prevention/adaptation. Therefore,
one significant aspect of this research is that it provides acomprehensive package to Bhutanese society rather thanjust to its research community. In the same vein, thesignificance of this joint research lies in the fact that it

works towards developing sustainable systems for GLOF
adaptation and prevention through technology transfer.
These two aspects guarantee high merits to Bhutanesesociety and meet standards for successful international
research collaboration. In this paper, we give an outlineof the GLOF project and achievements at this stage.

2. Structure and strategy of the research
project
The ultimate goal of this research is to assess objectively GLOF risk in Bhutan and attempt to implement
adaptation and prevention measures to curb both existing
and future GLOF-related risks. Toward this goal the following steps are being taken. The project consists ofthree research groups: a process-group, satellite-group
and assessment-group, and one counterpart in Bhutan(Department of Geology and Mines, DGM). The structure and strategy of the project is shown schematically in
Fig. 1.
2.1 Reselection and risk assessment of dangerous
glacial lakes
Over 40 glacial lakes in Nepal and Bhutan have been
listed for their potential risk (Mool et al., 2001a, 2001b).
Although many indices have been proposed to evaluate
GLOF risk so far (Bolch et al., 2008; Wang et al., 2008),
we think that the collapse of a damming moraine is essential to the release an effective amount of lake water, evenafter considering other triggers. On the basis of recently
gained knowledge on a link between the topography oflakes and surrounding areas (Fujita et al., 2008, 2009),
we propose a relative angle looking down from the lake
surface as a single parameter for identifying the potential
risk of a given glacial lake. The schematic figure in Fig. 2
explains the concept of the relative lookdown evaluation.

Fig. 1 Structure and strategy of the project for study on glacial lake outburst floods in the
Bhutan Himalayas.

Outline of Research Project on Glacial Lake Outburst Floods in the Bhutan Himalayas

5Fig. 2 Schematic figure of the concept of the relative lookdown
evaluation for GLOF risk. A lookdown angle of –10° is atentative value.

This idea is similar to the width-height ratio of the damming moraine, which has been proposed by Clague andEvans (2000). We simplify the dam-related parameters
into one because it is difficult to determine the boundaries of damming moraines on remotely sensed images.
Using this criterion, we chose pilot sites for our fieldsurvey. Our detailed analysis using ASTER data is now
ready for publication.
2.2 Field surveys of high-risk glacial lakes
We conducted field surveys of glacial lakes in the
Mangde-Chhu basin (Fig. 3), a previously unsurveyedriver basin in the middle part of Bhutan, in which a pilot
study pointed to GLOF potentials from seven glaciallakes (lakes with orange boundaries in Fig. 3, threepotentially dangerous glacial lakes are also shown in the
Lunana region) (Mool et al., 2001b). We set our focus on
the residual strength of the damming moraine and otherfactors leading to outbreaks, as displayed schematicallyin Fig. 4. We utilized different technologies developed indifferent disciplines such as river engineering, geotechnical and geophysical exploration, using two-dimensional resistivity profiling and a micro-tremor array
method to investigate the internal structure of moraines.
The survey included sounding and drawing of bathymetric maps. To conduct field surveys in the Zanam
region, one of the headwater regions in the Mangde-Chhu
basin (Fig. 3), we spent the first year checking local
accessibility and transportation and conducting preliminary field surveys of moraine structure, hydrology andglacier dynamics at pilot sites. In the second year, we
conducted intensive surveys throughout the MangdeChhu basin. In the third year (the last year of the project),
we made additional surveys not only in the MangdeChhu basin but also in the Lunana region to obtain dataon changes in glaciers and glacial lakes since theprevious surveys in 2004 (Fujita et al., 2008).
2.3 Hazard map of the Mangde-Chhu River
Numerical simulations to assess GLOF-associatedrisk for the Mangde-Chhu basin have been conducted(Koike & Takenaka, 2012). The breach model used inthese simulations calculated bed erosion and horizontal
widening of the outlet channel in the damming moraine

Fig. 3 Glacial lakes in the Zanam and Lunana regions, Bhutan
Himalayas. PDGL and AWS denote potentially
dangerous glacial lakes, which have been pointed out
by the ICIMOD report (Mool et al., 2001b), and an
automatic weather station installed near Lake Zanam F,
respectively. Light green shading denotes glacial lakes
for which we conducted bathymetry surveys throughthe project. SG denotes surveyed glaciers. The backimage was taken by ASTER in 2008.

Fig. 4 Possible triggers of glacial lake outburst floods.

by considering processes of sediment transportation andslope stability. Propagation of floods was calculatedusing a one-dimensional flood model, and then the highest water level was calculated using a two-dimensional
flood model with high-resolution DEMs (digital elevation models). Rising water levels, valley topography andlandslide risk on the river bank caused by flooding weretaken into account. The simulation outputs were flood
arrival times and the highest water level around targets
requiring protection (habitats or infrastructures), fromwhich a flood hazard map of the Mangde-Chhu basin wasconstructed.

6

K. FUJITA et al.

2.4 Understanding of glacial lake evolution
The above-described plans aim at directly assessing
and adopting GLOF risk for existing glacial lakes. In the
future it will also be essential to estimate possible
impacts from global warming on the formation andexpansion of glacial lakes. At present there is no established theory to explain the mechanism of glacial lake
evolution, whereas Sakai et al. (2009) have proposed apositive feedback process with respect to glacial lake
expansion by numerical simulation. Field surveys on theheat budget of glacial lakes, glacier dynamics, ice thickness of glaciers, meteorological conditions and otherparameters are needed to elucidate the underlying physics of glacial lake formation and expansion. In the firstyear, an automatic weather station (AWS) was set beside
Lake Zanam F (AWS in Fig. 3) to obtain meteorological
data. These data provide important meteorological information from the high Himalayas where observational
data have been scarce. Besides the dynamic approach, we
also examined topographical features of glaciers in
different states with respect to glacial lakes: having adeveloped glacial lake, a developing glacial lake, andwithout a glacial lake. We used topographical maps for
the Nepal Himalayas and our surveyed data from 2004
for the Bhutan Himalayas.

3. Major Results Obtained by Fall 2011
3.1 Results from remote sensing analysis
In order to update and improve the glacial lakeinventory for the Bhutan Himalayas, we used a new set ofsatellite data from the sensors on board the Advanced
Land Observing Satellite (ALOS, ‘Daichi’ in Japanese).
With their high spatial resolution and their efficacy inmaking DEMs, ALOS-based satellite data are particularly desirable for investigating glacial lakes. The accuracy and methodology for delineating glacial lakes are
confirmed with field survey data (Ukita et al., 2011). A
preliminary inventory was released in February 2011. An
outline of the remote sensing analysis is described by
Tadono et al. (2012) in this issue. We intend to complete
the inventory covering the Bhutan Himalayas, including
the Tibetan side, within this project.
3.2 Results from field observations
We have conducted three field trips to the MangdeChhu basin since the project was launched. We conducted bathymetric surveys for nine glacial lakes in thebasin (Lakes Zanam A, B, C, D, F and G, an unnamed one,and Lake Metatshota in Fig. 3). Five other lakes in the
Lunana and Gangju La regions were also surveyed.
Figure 5 shows our bathymetry of Lake Zanam C, which
was identified as a potentially dangerous lake in our
preliminary analysis (Fig. 6), whereas it had not been
selected as a potentially dangerous glacial lake (PDGL)in the previous ICIMOD report (Mool et al., 2001b). Our
analysis using ASTER data was unable to estimate how
the shoreline would change if the lake water weredrained; the bathymetry, which was obtainable only by an

Fig. 5 The bathymetry of Lake Zanam C. The longitudinal
depth profile in (b) is depicted along the yellow line in(a).

Fig. 6 The Zanam region of the Mangde Chhu headwaters,from the sky. Alphabetical letters denote lakes in theregion (see also Fig. 2). Photograph courtesy of Y.
Konagaya (Kawasaki Geological Engineering Co. Ltd.).

Outline of Research Project on Glacial Lake Outburst Floods in the Bhutan Himalayas

in-situ survey, was our primary information to evaluate
the flood water volume if a GLOF occured. The
measurement revealed that the flood water volume would
be constrained by the shallow water depth on the downstream side and suggested that Lake Zanam C was fairlysafe.
We performed geophysical explorations as well to
confirm the structure of the damming moraine because
the existence of ice within the moraine dam can significantly alter the strength of the dam (Hambrey et al.,2008). The detailed results are shown by Ohashi et al.
(2012) in this issue.
In addition to the GLOF issue, changes in glaciers arematter of debate in the Himalayan region (Cogley et al.,2010). In particular, observational evidence is scarce in
the Bhutan Himalayas. We updated terminus positionsand volume changes in small glaciers along the researchroute (SG in Fig. 3), which had been surveyed at the endof the 20th century (Naito et al., 2006). All of the surveyed glaciers showed obvious retreat and shrinkage.
The details are described by Naito et al. (2012) in thisissue.

Fig. 7 A scatter diagram showing the difference in height
between a lateral moraine and the glacier surface (verticalaxis) plotted against the glacier surface inclination(horizontal axis) for Himalayan debris-covered glaciers.
White triangles and solid circles indicate glaciers withglacial lakes and glaciers without glacial lakes, respectively. The gray dashed line represents the boundary
between glaciers with and without glacial lakes among
Himalayan debris-covered glaciers. The figure ismodified from Sakai and Fujita (2010).

7

3.3 Formation conditions of Himalayan glacial lakes
Besides the field observational data, the analysis ofwhich will take time, we worked on topographic maps
and remote sensing data to depict which parameters havedetermined the formation of glacial lakes. Sakai and
Fujita (2010) clarified that the formation conditions of a
glacial lake could be clearly expressed in terms of theinclination of the glacier surface and the amount of surface lowering on the debris-covered area of the glacier
since the Little Ice Age (LIA) in the Nepal and Bhutan
Himalayas (Fig. 7). The figure shows that debris-covered
glaciers with a growing or developed glacial lake
(longitudinal length > 1 km) have gentler inclinations andlarger surface lowering from the LIA than do glacierswithout glacial lakes. This relationship can be explainedby the contribution of calving of the terminus by ablation
at supraglacial ponds and by glacier ice dynamics. The
formation of a terminal glacial lake results in reduced
compression in the lower part of the glacier, as the glacierice at the terminus receives no pressure from adjacent iceor the terminal moraine. This reduced compression
results, in turn, in reduced emergence velocity (weakuplifting of the glacier surface), leading to further lowering of the glacier surface. Hence, glacial lake formation
involves a positive feedback to the lowering of the glaciersurface, meaning that glacial lakes form in association
with relatively large amounts of surface lowering.
Furthermore, glacial lakes contribute to the disintegrationof the glacier terminus and acceleration of the rate oflowering of the glacier surface. An overview with respect
to glacial lake formation is given by Sakai (2012) in thisissue.
3.4 A flood event from the Tshojo Glacier in 2009
On 29 April 2009, an unusual water discharge
occurred from the Lunana region. The source of the discharge was the Tshojo Glacier, 15 km in length and
20 km2 in area. This typical debris-covered glacier is oneof the biggest glaciers in the Bhutan Himalayas. Local
citizens, who had experienced the 1994 GLOF, werethrown into a commotion by this event, though there wasno damage. However this disturbance was the first such
experience after the 1994 GLOF. A discharge meter in the
Pho Chhu suggested the flood water volume to be morethan 0.5 million m3.
We carried out field surveys after the event in 2009

Fig. 8 Schematic profile of the Tshojo outburst event in 2009.

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K. FUJITA et al.

and 2010 and found deeply eroded channels on theglacier and the fan shaped deposit in front of the outlet.
These characteristic features suggest that flood waterwith a large amount of debris was transported fromupstream through subglacial and/or englacial channels(Fig. 8). In addition an analysis of multi-temporal remotesensing images revealed the abrupt disappearance of asupraglacial lake located 5.5 km upstream from the outlet.
Yamanokuchi et al. (2011) estimated the total volume of
the flood at 1.5 million m3 based on ALOS PRISM
DSMs, which were taken before and after the flood event.
This volume is three times more than the estimate fromthe downstream river gauge (0.5 million m3). This isequivalent to a water level lowering of 12.5 m. We
simply estimated, on the other hand, that the water level
lowering of the lake would have been 4.3 m from the lake
dimensions (0.118 km2) and flood volume (0.5 millionm3). Despite the remaining discrepancy with respect tovolume, we can conclude that this vanished lake was asource of this small GLOF event. More details on thisevent are described in Komori et al. (2012) in this issue.
3.5 Flood simulation and hazard map
The actual GLOF impact on the residential areas
downstream of the Mangde Chhu River basin was simulated by a numerical analysis with bathymetric profiles,
ALOS-based DEM and hydraulic aspects. We assessed
breach potentials of several glacial lakes in the basin,
including PDGLs nominated by ICIMOD (Mool et al.,2001b) by using the same soil parameters of the reproduced breach scenario of the Lugge Glacial Lakemoraine dam in the Lunana region, which burst in 1994.
Due to the wide crest and gentle slope of the moraine
dams, consequently, sediment transportation hardly
accelerates in the condition of normal inflow, and thebreach potential is comparatively lower than that of the
Lugge Glacial Lake.

Lake Metatshota is the largest glacial lake in the
Mangde Chhu River basin and is surrounded by an
undulating moraine. Although the breach potential of thedamming moraine is comparatively low as mentioned
above, we further simulated how the flood wave would
propagate along the river in the case of an outburst. The
total flood volume and breach peak discharge of Lake
Metatshota are estimated to be 18 million m3 and2,750 m3s-1 respectively, when the moraine dam
drastically starts to breach with an inflow to the lakeexceeding 50 m3 s-1. Assuming this probable large-scale
scenario, in which an outburst releases the lake water
immediately, the flood wave from Lake Metatshota
would arrive at Bjizam village, 62 km downstream of thelake, within three hours. The flood would rise to a peakdischarge of 2,000 m3 s-1 in a moment. Under thiscondition, the lower terrace plain of the village would be
affected and the National Highway across the river would
possibly be damaged (Fig. 9). The detailed results aredescribed by Koike and Takenaka (2012) in this issue.
3.6 Landslide mapping
Detection of landslide slopes is essential for hazard
assessment of GLOFs because the occurrence of GLOFs
may reactivate potential landslides through river bankerosion. We delineated landslide distribution in the
Mangde Chhu River basin through interpretation ofsatellite images and field surveys. We topographicallyclassified the detected landslides into two types; deepseated gravitational deformation (DSGD) and slides.
Mountain slopes in this area are widely occupied by old
landslides, some of which are over several km in width.
Deep-seated landslides located at undercut slopes along
the river may be reactivated by GLOFs and make slopes
unstable. Details are described by Higaki and Sato (2012)
in this issue.

Fig. 9 Simulated flood depth at Bjizam Village in the Mangde Chhu River basin. The village
is located 62 km downstream from Lake Metatshota (Koike & Takenaka, 2012).

Outline of Research Project on Glacial Lake Outburst Floods in the Bhutan Himalayas

9

Table 1 Technology transfer in the project (as of the end of October 2011).
Training in Bhutan
Type of training

Location
Upper Mangde
Chhu basin

On the job training
Lower Mangde
Chhu basin

Indoor training

Subject

Trainee No.

Trainer

PeriodProcess Group

20 weeks

2ESS

5 weeks

3

Assessment Group

5 weeks

Active fault surveys

2

Dr. Kumahara, Gunma
Univ.

3 weeks

Electric resistivity surveys

3ESS

5 weeks

Groundwater exploration

2ESS

2 daysSatellite data analyses

10

Satellite Group

3 weeks

Flood analyses with GIS

Glaciological surveys

4Land and lake surveys

3Electric resistivity surveys
Landslide surveys

5ESS

3 weeks

Soil testing in geotech
laboratory

1

Mr. Umemura, Nihon
Univ.

3 weeks

Tsukuba

Satellite data analyses

1Satellite Group

1 weekTokyo

Flood analyses with GIS

1ESS

1 weekKoriyama

Geotec laboratory

1

Mr. Umemura, Nihon
Univ.

1 weekTokyo

Electric resistivity survey

2

ESS

1 day

RS/GIS and Flood analyses

2

DGM office

Training in Japan
Short-term training(conducted by thisproject)

Long-term training
Tsukuba(ordinary plans in JICA
technical cooperation) Tsukuba

Flood analyses and planning2

1month
ICHARM

1monthField excursions

Mountain, earthquake and snow
Tohoku and Kanto
hazard and their mitigation
regions
works

4

Assessment Group

6 weeks

Activities in academic
society

Several cities in
Japan

5

All project members

10 daysPresentation of research
progress

ESS: Earth System Science Co.,Ltd., DGM: Department of Geology and Mines, Bhutan, ICHARM: International Center for Water Hazard
and Risk Management. JICA: Japan International Cooperation Agency.

3.7 Technology transfer
We are assisting our Bhutanese counterparts inenhancing their ability to cope with GLOF-related issues.
Within three years several ‘on the job training’ sessions(OJTs) both in the field and indoors were carried out(Table 1). These activities are approximated at eighty
man-months as of the end of October 2011. In addition,
several training sessions in Japan with field excursions
and attendance of scientific conferences were conducted
for nine Bhutanese counterparts (Table 1).
One of the most important OJTs was field observations and related logistics through our field surveys.
Bhutanese counterparts already have good experience
with respect to mountain fields so they could immediately acquire the techniques; for example how to conduct bathymetric surveys, glacier surveys, geophysicalexplorations on damming moraines and meteorologicalobservations. Although it is important to learn how toanalyze the data obtained, this is an ongoing effort in the
project. Further instructions on how to prepare and analyze satellite remote sensing data were given and in fact a
few Bhutanese counterparts took charge of delineating
glacial lakes in the specified basin (Tadono et al., 2012).

Training sessions on flood simulation and hazard mapping are also planned within this project period.
Exchange of information with respect to project progress
was performed through joint coordination committees
and science workshops, which were held in March of2009 and 2010.

4. Conclusions
The potential risks from Himalayan glacial lakes haveto be evaluated in an appropriate manner because feasible
allocation of finite financial and human resources is
crucial to dealing with the GLOF hazard issue. In thisarticle we gave an outline of our interdisciplinary projectfor GLOFs in the Bhutan Himalayas. We established an
up-to-date glacial lake inventory in the Bhutan
Himalayas based on ALOS data (Ukita et al., 2011). We
also re-evaluated PDGLs in the region based on the inventory. Bathymetric surveys, geophysical explorations
and meteorological observations were conducted in the
Zanam region, at the headwaters of the Mangde-Chhu
River basin, to evaluate the potential risk of GLOFs andthe possible amount of flood water discharge in the case

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K. FUJITA et al.

of a GLOF. Based on these field data, we performed
flood simulations and then constructed a hazard map
along the river, in which the danger of landslides along
the river was taken into account to evaluate the vulnerability of neighboring slopes.
On the basis of predictions on future glacial lake
evolution (Sakai & Fujita, 2010), a glacial lake monitoring system using satellite data from all-weather synthetic
aperture radar such as ALOS-PALSAR, TerraSAR-X andALOS-2 (Suzuki et al., 2011) would be helpful to
Himalayan countries. In the context of GLOF prevention,such a system can be used to single out lakes that needpreventive work. This also provides valuable information
for future watershed disaster management planning andland development downstream. In terms of prevention,lakes in early stages (smaller lakes) are relatively easier
to deal with cost-effectively, because their potential flood
volumes are less than those of well developed large lakes,
even if artificial expansion of the outlet triggers an outburst.
For prevention, the most effective method is to lower
the water level of lakes by draining. This, however, isexpensive and thus impractical, as the potentially
dangerous lakes in the Himalayan countries are typicallylocated in remote and high altitude areas. It would behighly desirable to build early-warning systems for taking GLOF countermeasures, which could alert residents
in the downstream regions.
Although our project is being conducted only in the
Bhutan Himalayas due to institutional constraints, we
believe that the course of our approach to this issue isadaptable to other Himalayan countries. The success of
this project might be confirmed when GLOF assessments
in other basins are performed by Bhutanese researchers.

Acknowledgements
This project ‘Study on Glacial Lake Outburst Floodsin the Bhutan Himalayas’ has been conducted under the
Science and Technology Research Partnership for
Sustainable Development (SATREPS) supported by theJapan Science and Technology Agency (JST) and theJapan International Cooperation Agency (JICA). We are
grateful for support from the Bhutanese Government. We
thank all collaborators in this project. Our thanks also go
to T. Watanabe and two anonymous reviewers for theirthoughtful comments.
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11

Koji FUJITA
Koji FUJITA is an Associate Professor at theGraduate School of Environmental Studies,
Nagoya University. He received his PhD (inScience) from Nagoya University. He has undertaken various field work in Nepal, Tibet, Bhutan,
Kyrgyzstan and Tajikistan, as well as overwintering at Dome Fuji Station, which is inland in east Antarctica. His research
has focused on fluctuations of Himalayan glaciers, ice-core based
paleoclimate reconstruction in the Asian highlands, and stable water
isotope climatology in Antarctica.

Kouichi NISHIMURA
Kouichi NISHIMURA is a Professor at theGraduate School of Environmental Studies,
Nagoya University. He earned his Doctor of
Science degree from Hokkaido University. He isinterested in various aspects of snow and ice
studies: for example, snow avalanche releasemechanisms and dynamics, blowing snow over the Antarctic ice sheet aswell as around fences along roads, and glacier lake outburst floods(GLOFs) in Nepal and Bhutan.

Jiro KOMORIJiro KOMORI is a JICA expert on technical/
research cooperation in Bhutan, and holds anappointment as a Contract Assistant Professor at
the Graduate School of Environmental Studies,
Nagoya University. As a JICA expert, he has
been dispatched to the newly established
Division of Glaciology at the Department of Geology and Mines, Royal
Government of Bhutan since 2009. Originally he worked for four years as
an engineer at a geological consulting company and subsequently for four
years at Nihon University as a laboratory assistant until 2000. He obtained
his PhD in paleoenvironmental studies from the Graduate School of Tokyo
Metropolitan University in 2005. As a graduate student, he also started to
study subjects such as disaster prevention related to recent environmental
change. His first field survey of glaciers and glacial lakes was in the
Bhutan Himalayas in 2002. This brought an opportunity for precious
experience and many encounters in Bhutan to not only for himself but also
his family. He currently has a keen interest and is seeking ways todisseminate the results of this research and educate the younger generation
regarding the issues of environmental change and loss of interest in thenatural sciences.

Shuji IWATA
Shuji IWATA was born in Kobe, Japan in 1946 andis a Professor Emeritus of Geography at theCollege of Tourism, Rikkyo University. He
received his Ph.D. (in Science) from Tokyo
Metropolitan University. He has investigatedglacial geomorphology and mountain geoecology in the Himalayas, Tibetan Plateau, Tienshan and Pamir, as well asJapan’s high mountains. He has also worked on glacial landforms in the
Sør Rondane Mountains of East Antarctica, and Iceland. His research has
focused on GLOFs in the Bhutan Himalayas since 1998.

K. FUJITA et al.

12
Jinro UKITA

Jinro UKITA has been a Professor of the Facultyof Science at Niigata University, Niigata Pref.,Japan since 2007. He received two M.S. degrees,
one in Oceanography from the University of
British Columbia and the other Atmospheric
Sciences from the University of Washington,
U.S., and his Ph.D. from Hokkaido University, Hokkaido Pref., Japan in
1998. From 1995 to 1996 he served as a lecturer at the University of Tokyo,
and then joined the National Space Development Agency of Japan(NASDA, the former JAXA), where he served as a research scientist anddeveloped a Japan-US joint science program for the International Arctic
Research Center (IARC) in Fairbanks, Alaska, U.S. as a sub-leader. In
2000 he moved to the U.S. to join the cryosphere programme at NASA
Goddard Space Flight Center where he researched sea-ice. Between 1998
and 2004 he was an affiliated research scientist at the Lamont-Doherty
Earth Observatory of Columbia University, U.S.

Takeo TADONO
Takeo TADONO is an Associate Senior Researcher
at the Earth Observation Research Center(EORC), Japan Aerospace Exploration Agency(JAXA), Tsukuba, Ibaraki Pref., Japan, and is incharge of calibrating and validating optical
instruments on the Advanced Land Observing
Satellite (ALOS) and ALOS follow-on missions. He received his B.E.
degree in 1993, M.E. degree in 1995, and Ph.D. in 1998 in Civil
Engineering from Nagaoka University of Technology, Niigata Pref., Japan.
His research interests are calibration and validation of high-resolution
optical instruments and the development of algorithms for retrieving
geophysical and hydrological parameters from remote sensing data.

Toru KOIKE
Toru KOIKE is a Deputy General Manager of theEnvironmental & Disaster Management Department at Earth System Science Co., Ltd. He has
been working in the field of disaster management,
including geological and river engineering under
Official Development Assistance funding fromthe Japanese government. During 2000-2002, he lived in Bhutan andworked for the Department of Geology & Mines. Currently he is working
in disaster related projects in Thailand, Vietnam, Bhutan, Bolivia andCaribbean countries.

(Received 11 November 2011, Accepted 13 February 2012)