Changing Glaciers and Hydrology in Asia - Environmental Health at ...

Human health and ecosystem impacts are likely to result from the environmentalimpacts of changes in the hydrologic systems, of which glaciers are a component. Theremay be too much water in the form of floods, which may overwhelm local water andsanitation systems and raise the risk of diarrheal and other diseases, ruin agriculturalcrops and infrastructure, destroy livelihoods, and increase health risks from standingwater that may be breeding grounds for disease vectors. There may be too little waterin the form of longer times between rains or increased aridity, which will result in lesswater available for drinking, sanitation, and food and hand washing – all raising healthrisks. Less water will be available for crops and ecosystems. Pollutant concentrationswill be proportionately greater in less water. Scarcity of water also means that moretime must be devoted to finding and carrying water. In addition, there may be changes inwhen water is plentiful, causing uncertainties about what to plant and when, resulting inlikely decreases in crop yields.Current existing health, ecosystem, and pollution issues make communities morevulnerable to any changes in their water systems. Glacier melt and its water-relatedchanges will likely exacerbate current vulnerabilities, such as demographic factors(population size and density, fertility rates, and population momentum), high burden ofdisease, degradation of ecosystems, and poor air quality. These current vulnerabilitieswill make communities less resilient to any glacier-melt-related shifts in hydrologicsystems.Based on these assumptions, the study team next identified societal and ecological vulnerabilitiesto potential impacts associated with glacier melt. For this task, the team first focused on thecollection of geo-referenced data from the region, using the data sets most likely to providesubstantive data for subsequent analysis (e.g., population distribution, river basin areas, primaryagricultural products, and sensitive ecological areas or regions). Maps with overlays wereprepared for identifying glacier melt vulnerabilities that overlap with USAID sectors (health,agriculture, environment, biodiversity, conflict/security, and water).At a March 31-April 1, 2010, workshop, the project team, in consultation with USAID teammembers, drafted a set of issue areas and key vulnerabilities (described below) related to glaciermelt in the larger context of high-altitude hydrology. Additional types of data to be mappedwere then identified. All maps have been produced using GIS technology.3.1 NEAR-TERM ISSUES RESULTING FROM CURRENT GLACIER CHANGESThe most visible near-term issue is the danger of GLOFs, which are described in Section 2.Another issue is the projected near-term retreat and disappearance of some glaciers thatprovide fresh water for nearby communities.A comprehensive database of glacier lakes and the danger of GLOFs has not yet been compiled,although remote sensing has been used to examine glacier lakes. However, remote sensing isnot necessarily an accurate way to determine whether or not a particular glacier lake presentsan outburst flood danger. For instance, Byers (2009) reports on ground-based expeditions thathave corrected several of the remote sensing results.30