Hydrology of the Upper Indus Basin Under Potential Climate Change Scenarios

The mountain regions of the Hindu Kush, Karakoram and Himalaya (HKKH) are the "third pole'' of our planet, and the glaciers in this area are "water towers'' of Asia. Recent studies postulated the existence of a "Karakoram anomaly'', i.e. with substantially unchanged ice cover during the last decade, against noticeable area loss worldwide. Yet, recent major floods occurring in Pakistan and the Karakoram area, may represent an effect of modified climate in the area, carrying heavier precipitation in the Monsoon season, and possibly faster ice melting. We present here the results of the SHARE-Paprika project of the EvK2CNR Committee of Italy, aiming at evaluating the impact of climate change on the hydrology of the upper Indus river. We focus here on a particular watershed, the Shigar river closed in Shigar, with an area of about 7,000 km(2) and fed by seasonal melt from two major glaciers (Baltoro and Biafo). Based upon data gathered during three field campaigns we set up a semi-distributed, altitude belt based hydrological model, providing acceptable depiction of in stream flows, and snow and ice cover dynamics. We then project the future (until 2,100) hydrological cycle in the area by feeding the hydrological model with future precipitation and temperature (plus downscaling, whenever necessary) from a number of climate models, under different RCP scenarios.