These challenges will be accentuated by climate change. It ranges from under 400 mm over approximately 40 per cent of the country, particularly in the Gorno-Badakhshan Autonomous Region, up to 1,500 mm in the central mountainous regions and their river basins. In total, the annual amount of precipitation is 98.6 km3 of water. Sixteen glaciers, such as the Fedchenko and Grumm-Grzymailo glaciers, have a length of more than 16 kilometers. The total amount of water from glaciers was estimated at 845 km3 in 2006. The share of glacial water usually does not exceed 25 per cent of the annual flow of the rivers, as in the winter period the rivers are rather fed by groundwater.