|
|
Mountain cryosphere provides fresh water and other ecosystem services to half of humanity
. The loss of mountain cryosphere due to global warming is already evident in many parts of the world, which has direct implications to people living in mountain areas and indirect implication to people living downstream of glaciated river basins. Despite the growing concerns, the relationship between cryosphere change and human society has yet to be assessed systematically. A better understanding of how cryosphere change affects human systems and human security would provide much needed support to the planning of global and regional actions to mitigate impacts and facilitate adaptation. This paper synthesizes the current evidence for and potential impacts of cryosphere change on water, energy, food, and the environment in different mountain regions in the world. The analysis reveals that the changes in the cryosphere and the associated environmental change has already impacted people living in high mountain areas and are likely to introduce new challenges for water, energy, and food security, and exacerbate ecosystem and environmental degradation in the future. The effects of cryospheric changes are also likely to extend to downstream river basins where glacier melt contributes significantly to dry season river flows and supports irrigation, fisheries, and navigation, as well as water supply to many big cities. Appropriate adaptive and mitigative measures are needed to prevent risks and uncertainties being further compounde
Read More
|
|
|
This First HKH Assessment Report consists of 16 chapters, which comprehensively assess the current state of knowledge of the HKH region, increase the understanding of various drivers of change and their impacts, address critical data gaps and develop a set of evidence-based and actionable policy solutions and recommendations
. These are linked to nine mountain priorities for the mountains and people of the HKH consistent with the Sustainable Development Goals
Read More
|
|
|
Brun, F.; Buri, P.; Miles, E. S.; Wagnon, P.; Steiner, J.; Berthier, E.; Ragettli, S.; Kraaijenbrink, P.; Immerzeel, W. W.; Pellicciotti, F.
Mass losses originating from supraglacial ice cliffs at the lower tongues of debris-covered glaciers are a potentially large component of the mass balance, but have rarely been quantified
. In this study, we develop a method to estimate ice cliff volume losses based on high-resolution topographic data derived from terrestrial and aerial photogrammetry. We apply our method to six cliffs monitored in May and October 2013 and 2014 using four different topographic datasets collected over the debris-covered Lirung Glacier of the Nepalese Himalayas. During the monsoon, the cliff mean backwasting rate was relatively consistent in 2013 (3.8 ± 0.3 cm w.e. d −1 ) and more heterogeneous among cliffs in 2014 (3.1 ± 0.7 cm w.e. d −1 ), and the geometric variations between cliffs are larger. Their mean backwasting rate is significantly lower in winter (October 2013–May 2014), at 1.0 ± 0.3 cm w.e. d −1 . These results are consistent with estimates of cliff ablation from an energy-balance model developed in a previous study. The ice cliffs lose mass at rates six times higher than estimates of glacier-wide melt under debris, which seems to confirm that ice cliffs provide a large contribution to total glacier melt
Read More
|
|
|
This open access volume is the first comprehensive assessment of the Hindu Kush Himalaya (HKH) region
. It comprises important scientific research on the social, economic, and environmental pillars of sustainable mountain development and will serve as a basis for evidence-based decision-making to safeguard the environment and advance people’s well-being. The compiled content is based on the collective knowledge of over 300 leading researchers, experts and policymakers, brought together by the Hindu Kush Himalayan Monitoring and Assessment Programme (HIMAP) under the coordination of the International Centre for Integrated Mountain Development (ICIMOD). This assessment was conducted between 2013 and 2017 as the first of a series of monitoring and assessment reports, under the guidance of the HIMAP Steering Committee: Eklabya Sharma (ICIMOD), Atiq Raman (Bangladesh), Yuba Raj Khatiwada (Nepal), Linxiu Zhang (China), Surendra Pratap Singh (India), Tandong Yao (China) and David Molden (ICIMOD and Chair of the HIMAP SC). This First HKH Assessment Report consists of 16 chapters, which comprehensively assess the current state of knowledge of the HKH region, increase the understanding of various drivers of change and their impacts, address critical data gaps and develop a set of evidence-based and actionable policy solutions and recommendations. These are linked to nine mountain priorities for the mountains and people of the HKH consistent with the Sustainable Development Goals. This book is a must-read for policy makers, academics and students interested in this important region and an essentially important resource for contributors to global assessments such as the IPCC reports
Read More
|
|
|
2017 was final year in ICIMOD's third medium-term action plan (2013-2017)
. This report documents several stories showing the cumulative impact of ICIMOD’s work over the last five years. They show how we combine efforts on multiple fronts – from working with communities, engaging policy makers and promoting collaboration across borders to generating new knowledge and building capacity – to create positive change in the Hindu Kush Himalaya (HKH). During this timeframe many important lessons have emerged to help us chart the way forward
Read More
|
|
|
Background The Cryosphere Monitoring Programme Bhutan (CMP–B) carries out annual field monitoring on the benchmark Thana glacier, collects and analysis data from automatic weather stations and hydrological monitoring stations in selected research sites downstream
. CMP–B also monitors glacial lakes and assesses socio-economic vulnerability in the Punatsang Chu basin. It produces remote sensing data, analyses, and inventories on the cryosphere for the entire Bhutan Himalaya. The programme is funded by the Government of Norway and implemented by the National Center for Hydrology and Meteorology (NCHM) and the International Centre for Integrated Mountain Development (ICIMOD)
Read More
|
|
|
The International Centre for Integrated Mountain Development (ICIMOD) works with its implementing partners to develop a coordinated scheme for field and remote sensing monitoring and modelling, and to assess the state and processes of the cryosphere in the Hindu Kush Himalaya (HKH)
. Activities under this programme are also geared towards improving transboundary water resource management and expanding global knowledge of glaciers, glacial lakes, permafrost, snow, climate change impact, and hydrometeorology in the HKH
Read More
|
|
|
Maharjan, S. B.; Mool, P. K.; Lizong, W.; Xiao, G.; Shrestha, F.; Shrestha, R. B.; Khanal, N. R.; Bajracharya, S. R.; Joshi, S.; Shai, S.; Baral, P.
This report provides comprehensive information about the glacial lakes of five major river basins of the Hindu Kush Himalaya (HKH) — Amu Darya, Indus, Ganges, Brahmaputra, and Irrawaddy, including Mansarovar Interior Basin — representing the year 2005, which helps to fill the data gap of glacial lakes information in the region
. This is the first comprehensive knowledge upon the distribution of glacial lakes for the HKH providing baseline data for further investigation of glacial lakes, GLOF hazards and risk assessment, and mitigation measures. This inventory of glacial lakes was prepared with consistent, homogeneous, much narrower temporal range and single source data with a semi-automatic method. For the consistency of glacier and glacial lakes data, the same time satellite images were used to delineate both glaciers and glacial lakes. The glacier inventory data and report was published in 2011. The glacial lake boundaries were delineated using an automatic method on Landsat images from the year 2005±2 years. The automatic method to delineate the glacial lake boundaries by defining the threshold condition of band ratio images made the process of mapping and monitoring of glacial lakes faster. It is challenging to apply the method throughout the region as it is difficult to get good quality of images with the least amount of snow cover, cloud cover, and shadow portion due to inconsistent and analogous climatic conditions in the region. So some of the lakes were manually digitized by validating on high resolution images in Google Earth as well as comparing with previous inventory data wherever available. This report also provides the modified classification schemes of glacial lakes from previous reports to make it consistent throughout the region. This inventory includes all the lakes in front of and on or beside a glacier or in the lowland formed by paleo-glaciation
Read More
|
|
|
Over Saint-Sorlin Glacier in the French Alps (45° N, 6
.1° E; ∼ 3 km2) in summer, we study the atmospheric surface-layer dynamics, turbulent fluxes, their uncertainties and their impact on surface energy balance (SEB) melt estimates. Results are classified with regard to large-scale forcing. We use high-frequency eddy-covariance data and mean air-temperature and wind-speed vertical profiles, collected in 2006 and 2009 in the glacier's atmospheric surface layer. We evaluate the turbulent fluxes with the eddy-covariance (sonic) and the profile method, and random errors and parametric uncertainties are evaluated by including different stability corrections and assuming different values for surface roughness lengths. For weak synoptic forcing, local thermal effects dominate the wind circulation. On the glacier, weak katabatic flows with a wind-speed maximum at low height (2–3 m) are detected 71 % of the time and are generally associated with small turbulent kinetic energy (TKE) and small net turbulent fluxes. Radiative fluxes dominate the SEB. When the large-scale forcing is strong, the wind in the valley aligns with the glacier flow, intense downslope flows are observed, no wind-speed maximum is visible below 5 m, and TKE and net turbulent fluxes are often intense. The net turbulent fluxes contribute significantly to the SEB. The surface-layer turbulence production is probably not at equilibrium with dissipation because of interactions of large-scale orographic disturbances with the flow when the forcing is strong or low-frequency oscillations of the katabatic flow when the forcing is weak. In weak forcing when TKE is low, all turbulent fluxes calculation methods provide similar fluxes. In strong forcing when TKE is large, the choice of roughness lengths impacts strongly the net turbulent fluxes from the profile method fluxes and their uncertainties. However, the uncertainty on the total SEB remains too high with regard to the net observed melt to be able to recommend one turbulent flux calculation method over another
Read More
|
|
|
Changes in glacial lakes and the consequences of these changes, particularly on the development of water resources and management of glacial lake outburst flood (GLOF) risk, has become one of the challenges in the sustainable development of high mountain areas in the context of global warming
. This paper presents the findings of a study on the distribution of, and area changes in, glacial lakes in the Koshi basin in the central Himalayas. Data on the number of glacial lakes and their area was generated for the years 1977, 1990, 2000, and 2010 using Landsat satellite images. According to the glacial lake inventory in 2010, there were a total of 2168 glacial lakes with a total area of 127.61 km2 and average size of 0.06 km2 in the Koshi basin. Of these, 47% were moraine dammed lakes, 34.8% bedrock dammed lakes and 17.7% ice dammed lakes. The number of glacial lakes increased consistently over the study period from 1160 in 1977 to 2168 in 2010, an overall growth rate of 86.9%. The area of glacial lakes also increased from 94.44 km2 in 1977 to 127.61 km2 in 2010, a growth rate of 35.1%. A large number of glacial lakes in the inventory are small in size (≤ 0.1 km2). End moraine dammed lakes with area greater than 0.1 km2 were selected to analyze the change characteristics of glacial lakes in the basin. The results show that, in 2010, there were 129 lakes greater than 0.1 km2 in area; these lakes had a total area of 42.92 km2 in 1997, increasing to 63.28 km2 in 2010. The distribution of lakes on the north side of the Himalayas (in China) was three times higher than on the south side of the Himalayas (in Nepal). Comparing the mean growth rate in area for the 33 year study period (1977-2010), the growth rate on the north side was found to be a little slower than that on the south side. A total of 42 glacial lakes with an area greater than 0.2 km2 are rapidly growing between 1977 and 2010 in the Koshi basin, which need to be paid more attention to monitoring in the future and to identify how critical they are in terms of GLOF
Read More
|
email alert
or subscribe to the 
RSS feed.
