Assessing the effects of precipitation and temperature changes on hydrological processes in a glacier‐dominated catchment

The processes by which climate change affects streamflow in alpine river basins are not entirely understood. This study evaluated the impacts of temperature and precipitation changes on runoff and streamflow using glacier‐enhanced Soil and Water Assessment Tool model. The study used observed and detrended historical meteorological data for recent decades (1961–2005) to analyse individual and combined effects of temperature and precipitation changes on snow and glacier melts and discharges in the Sary‐Djaz‐Kumaric River Basin (SRB), Tianshan Mountains. The results showed a 1.3% increase in annual snowmelt in the basin, mainly because of an increase in precipitation. Snowmelt in the basin varied seasonally, increasing from April through May because of increasing precipitation and decreasing from July through September because of rising temperature. Glacier melt increased by 5.4%, 5.0% of which was due to rising temperature and only 0.4% due to increasing precipitation. Annual streamflow increased by 4.4%, of which temperature and precipitation increases accounted for 2.5% and 1.9%, respectively. The impacts of temperature and precipitation changes on streamflow were especially significant after 1980 and even more so in September. Glacier melt, due to temperature rise, was the dominant driver of increasing streamflow in the glacier‐dominated SRB, Tianshan Mountains. Copyright © 2015 John Wiley & Sons, Ltd.