Large losses in glacier area and water availability by the end of the twenty-first century under high emission scenario, Satluj basin, Himalaya

Glaciers in the Satluj river basin are likely to lose 53% and 81% of area by the end of the century, if climate change followed RCP 8.5 scenario of CNRMCM5 and GFDL-CM3 models respectively. The large variability in area loss can be due to difference in temperature and precipitation projections. Presently, Satluj basin has approximately 2000 glaciers, 1426 sq. km glacier area and 62.3 Gt glacier stored water. The current mean specific mass balance is –0.40 m.w.e. a–1. This will change to –0.42 and – 1.1 m.w.e. a–1 by 2090, if climate data of CNRM-CM5 and GFDL-CM3 are used respectively. We have used an extreme scenario of GFDL-CM3 model to assess the changes in the contribution of glacier melt to the Bhakra reservoir. Mass balance model suggests that glaciers are contributing 2 km3 a–1 out of 14 km3 of water. This will increase to 2.2 km3 a–1 by 2050, and then reduce to 1.5 km3 a–1 by the end of the century. In addition, loss in glacier area by the end of century, will also increase the vulnerability of mountain communities, suggesting need for better adaptation and water management practices.