HIMALA: Climate Impacts on Glaciers in the Himalayan Region
October 26, 2012 15:26:05
Description of Problem
Glaciers are the largest reservoir of freshwater on Earth supporting one third of the world’s population. Himalayas possess one of the largest resources of snow and ice, which act as a freshwater reservoir for more than 1.3 billion people. Monitoring glaciers is important to assess the overall health of this reservoir. Glaciers and snowfields also form potential hazards in the Himalayas, and in similarly glacierised regions of the world. Water resources will be affected by climate change as well as population growth, changing economic activity, land use change, rapid urbanization and inefficient water use. National governments have limited capacity to determine and accurately predict possible impacts to water resources due to scarcity of hydrometeorological data, limited technical capacity, and the transboundary nature of many major river systems. This has also led to recent controversies surrounding the fate of Himalayan glacier melt, which highlight the need for further glaciological and hydrological research in this region.
The HIMALA project aims at developing a system that will aid populations at risk on early warning of floods, droughts and other water and climate-induced natural hazards in the Himalayan region. Among our main goals are to: (i) introduce the use of NASA Earth Science products and models to the International Center for Integrated Mountain Development (ICIMOD) and its member countries, through collaboration with USAID (the United States Agency for International Development) and USGS (the U.S. Geological Survey), (ii) enhance the decision making capacity of ICIMOD and its member countries for management of water resources (floods, agricultural water) in the short (snow, rainfall) and the long-term (glaciers), and (iii) provide projections of climate change impacts on water resources through 2100 using the IPCC models.
Scientific Objectives and Approach
To accomplish the HIMALA project goals, we focus on creating an end-to-end sub-basin prototype hydrological model which includes both snow and glacier melt that contributes to stream flow. Specific objectives include:
Create a new, area -wide snow water equivalent and snow extent product that allows monitoring of melt water in the region on a daily basis;
Build on existing regional modeling capacity to integrate snow and glaciers outflow to primary river basins (Ganges, Indus and Brahmaputra);
Provide a methodology that allows the intersection snow extent with glacier area maps to determine water outflow from melting glaciers using mass balance equations;
Engage ICIMOD national members in their efforts to monitor river flow using the GeoSFM hydrologic models, with new elements that incorporate melt water from the cryosphere into system;
Enable ICIMOD members to interpret and use snow extent products and to map and monitor glaciers in their river basins.
Establish capability at ICIMOD to effectively understand and monitor the impacts of short and long term climate variability on hydrological resources
The first phase of the project focuses on the development, testing and evaluation of the prototype modeling framework in three pilot river-basins. Jhelum river, in the Indus River Basin, Koshi river, in the Ganges River Basin, and Manas river, a tributary of the Brahmaputra River Basin, have been selected as our pilot basins for initial development of the modeling framework (Figure 1). The sites were selected based on the climatic and geographic diversity of the Hindu Kush-Himalayan (HKH) region, and also due to availability of observations and strong interest by partners in each country who will be willing to participate in the demonstration project. We have identified and acquired the available in-situ data for the project and also acquired relevant satellite images and other regional/global data products (e.g. MODIS snow cover, AMSR-E based SWE, NOAA-Snow cover).
Snow- and glacier-melt and outflow in the study region are estimated using a spatially distributed version of the Utah Energy Balance (UEB) snow accumulation and ablation model. Gridded flow from the cryosphere from the UEB will be ingested into the USGS Geospatial Stream Flow Model (GeoSFM), and can be used with any streamflow model. Digital elevation model topography, land cover, and soil information are used to derive and parameterize the sub-basins. The hydrological model is then forced by daily estimates of precipitation and evapotranspiration to predict daily discharge at any point in the catchment and is then validated using hydrological station information.
After completing testing and evaluation in the pilot basins, the new modeling framework will be upscaled to other basins in the Himalayan region. Climate data from the IPCC AR4 model scenarios will be incorporated into the analysis. These studies will enable long term estimates of the impact of precipitation dynamics on long term river flow in the region.
Other Publications and Conferences
Brown M.E., H. Ouyang, S. Habib, B. Shrestha, M. Shrestha, P. Panday, M. Tzortziou, F. Pollicelli, G. Artan, A. Giriraj, S. Bajracharya, A. Racovinteanu, 2010, “HIMALA: Climate Impacts on Glaciers, Snow and Hydrology in the Himalayan Region”, Mountain Research and Development, 30(4): 401-404
Racoviteanu A., G. Artan, M. Shrestha, S. Bajracharya, P. Mool, G. Amarnath, M. Brown, S. Habib, M. Tzortziou, and H. Ouyang, “HIMALA: Understanding the contribution of glacier and snowmelt in the Himalaya using a spatially-distributed energy balance model and remotely sensed data”, Geophysical Research Abstracts Vol. 13, EGU2011-10325, EGU General Assembly 2011, Vienna, Austria
Fig. 1 – Three specific river basins were selected where we will implement the model first: Koshi, Manas, and Jehlum.