Announcement of Data Release Glacial Lake Inventory of Bhutan using ALOS (Daichi) Data
The Japan Aerospace Exploration Agency (JAXA) is cordially
announcing public release of "Glacial Lake Inventory of Bhutan
using the Advanced Land Observing Satellite (ALOS, nicknamed
"Daichi") Data" (evaluation version). In the Himalayan region,
there are numerous lakes in the vicinity of glaciers. These glacial
lakes impose potential risks for sudden outbursts and consequent
floods. This type of flooding event is referred to as a glacial
lake outburst flood (GLOF), which occurs frequently enough in the
Himalayan region. With a growing amount of public and scientific
concern about hazards, climate change, and water management
associated with GLOFs, the "Bhutan GLOF Project" (*1) aims at
updating and improving glacial lake inventory for Bhutan using new
and high spatial resolution data from ALOS. The motivation for this
release is to support the research community and various domestic
and international projects. By releasing the evaluation version, we
hope to collect comments and suggestions for the preparation of the
full release of the inventory, now scheduled in the spring of
2012.
The inventory is based on images taken between 2006 and 2011 from
the two optical instruments, the Panchromatic Remote-sensing
Instrument for Stereo Mapping (PRISM) and the Advanced Visible and
Near Infrared Radiometer type 2 (AVNIR-2) onboard ALOS. The
construction procedure consists of ortho-rectification, geometric
correction, pan-sharpening, and digitization to extract water
bodies. Glacial lakes included in the inventory are bodies of water
that lay between the terminus of the mother glacier and the Little
Ice Age moraine. Lakes located within 2 km of the Little Ice Age
moraine down-valley are also included to take into account a
possible flooding event with multiple lakes being involved. In
addition, supraglacial lakes on debris-covered glaciers are
included. Finally, we set 0.01 km2 as the minimum lake
size considering small lakes contribute a less amount of GLOFs'
risk. For this release we selected the Mangde Chu sub-basin,
located in the central Bhutan. The parameters included in the
inventory are ID, latitude, longitude, area, length, width, and
some references in addition to a shape file for each lake. There
are 93 glacial lakes in the Mangde Chu sub-basin.
Figure 1 shows the pan-sharpended image covering Bhutan overlaid
the glacial lakes inventory (yellow polygons), Mangde Chu sub-basin
(red line) and the Bhutanese border (gray line). Figure 2 provides
the detailed image over Metathota glacial lake (yellow polygons)
with ground truth data by GPS measurements in 2010 (green line).
The red polygons indicate existing inventory provided in
2000.
*1 The project is a collaborative work of Nagoya University, Rikkyo
University, Hokkaido University, National Research Institute for
Earth Science and Disaster Prevention (NIED), Hiroshima Institute
of Technology, Japan Agency for Marine-Earth Science and Technology
(JAMSTEC), Remote Sensing Technology Center of Japan (RESTEC),
Niigata University, Research Institute for Humanity and Nature
(RIHN), Earth System Science Co.,Ltd. (ESS), Hirosaki University,
Nihon University, Teikyo Heisei University, Gunma University, Keio
University and the Department of Mineral and Geology (DGM) of the
Royal Government of Bhutan supported by the Japan Science and
Technology Agency (JST) and the Japan International Cooperation
Agency (JICA) under the "Science and Technology Research
Partnership for Sustainable Development" (SATREPS).
Link to the Inventory
https://www.eorc.jaxa.jp/ALOS/en/bhutan_gli/index.htm
(in English)
https://www.eorc.jaxa.jp/ALOS/bhutan_gli/index.htm
(in Japanese)