Glaciers and glacial lakes: indicators of global climate change
The impact of climate change on Himalayan glaciers is becoming apparent. Studies show that most valley glaciers are retreating. Vertical shifts of up to 100m have been recorded during the last fi fty years with retreat rates of 50m per year. There is evidence that glaciers have been melting faster in recent decades. If the present trend continues, it is estimated that most valley glacier trunks and smaller glaciers will disappear by 2050 AD. As valley glaciers retreat, glacial lakes can form and many are observed at elevations of around 4500m. With increasing amounts of water in these lakes, glacial lake outburst fl oods (GLOFs) are inevitable. Precautionary measures are needed so that loss due to such events can be avoided. Climate change in general and retreating glaciers and GLOFs in particular will effect water resources, the economy and livelihoods downstream.