The linked (open access) research concludes that beginning now more and more people, up to 2 billion people, will increasingly suffer from water shortages due to climate change:
Justin S Mankin, Daniel Viviroli, Deepti Singh, Arjen Y Hoekstra and Noah S Diffenbaugh (2015), "The potential for snow to supply human water demand in the present and future", Environmental Research Letters, Volume 10, Number 11
http://iopscience.iop.org/article/10.1088/1748-9326/10/11/114016Abstract: "Runoff from snowmelt is regarded as a vital water source for people and ecosystems throughout the Northern Hemisphere (NH). Numerous studies point to the threat global warming poses to the timing and magnitude of snow accumulation and melt. But analyses focused on snow supply do not show where changes to snowmelt runoff are likely to present the most pressing adaptation challenges, given sub-annual patterns of human water consumption and water availability from rainfall. We identify the NH basins where present spring and summer snowmelt has the greatest potential to supply the human water demand that would otherwise be unmet by instantaneous rainfall runoff. Using a multi-model ensemble of climate change projections, we find that these basins (which together have a present population of ~2 billion people) are exposed to a 67% risk of decreased snow supply this coming century. Further, in the multi-model mean, 68 basins (with a present population of >300 million people) transition from having sufficient rainfall runoff to meet all present human water demand to having insufficient rainfall runoff. However, internal climate variability creates irreducible uncertainty in the projected future trends in snow resource potential, with about 90% of snow-sensitive basins showing potential for either increases or decreases over the near-term decades. Our results emphasize the importance of snow for fulfilling human water demand in many NH basins, and highlight the need to account for the full range of internal climate variability in developing robust climate risk management decisions.
See also:
http://in.reuters.com/article/2015/11/12/us-usa-climate-water-idINKCN0T10OO20151112Extract: "Large swathes of the northern hemisphere, home to some 2 billion people, could suffer increasing water shortages due to shrinking snowpacks, researchers said on Thursday.
Data shows reduced snowpacks - the seasonal accumulation of snow - will likely imperil water supplies by 2060 in regions from California's farmlands to war-torn areas of the Middle East, according to a team of scientists in the United States and Europe.
In total, nearly a hundred water basins dependent on snow across the northern hemisphere run the chance of decline.
"Water managers in a lot of places may need to prepare for a world where the snow reservoir no longer exists," said Justin Mankin, the study's lead author and a researcher at Columbia University's Earth Institute in New York, in a statement."