Skip to main content

Sign up for our newsletter.

Quality journalism. Progressive values. Direct to your inbox.

Nearly a hundred basins worldwide which rely on snow for water supply face a 67 percent chance of decline by 2060. (Photo: NPS Climate Change Response/flickr/cc)

Declining Snowpack Threatens Water Supply for Billions Worldwide

'Water managers in a lot of places may need to prepare for a world where the snow reservoir no longer exists.'

Nadia Prupis

Vast areas of the northern hemisphere that are home to nearly two billion people face dangerous water shortages due to shrinking snowpacks, according to a new study released Thursday.

Less snowfall and earlier melting over the next century, coupled with the current trajectory of greenhouse gas emissions, means that people living in nearly a hundred watershed basins worldwide which rely on melting snow for water supply face a 67 percent chance of decline by 2060. That figure remains true even if present demand does not increase.

"Snow is important because it forms its own reservoir," said lead author Justin Mankin of Columbia University. "But the consequences of reduced snowpack are not the same for all places—it is also a function of where and when people demand water. Water managers in a lot of places may need to prepare for a world where the snow reservoir no longer exists."

The most at-risk basins lie in the American West and South, southern Europe, the Middle East, and central Asia, according to the report, published in Environmental Research Letters.

Using two sets of climate models, the team of U.S. and European researchers predicted future changes in snow and rain runoffs. For basins in the Duero-Adour in northern Portugal and Spain, the Central Apennines in Italy, and the Rio Grande in Texas and Mexico, which are dependent on snow, the findings showed water declines even in best-case scenarios.

But even basins that meet their water demand through rainfall are at risk.

Climate change "also shifts an additional 68 basins to have spring and summer rainfall runoff that is insufficient to meet human water demand, even without accounting for increases in demand that are likely to arise from population growth and economic development," the report states.

According to Mankin, those factors are harder to estimate.

"We only consider changes in climate, but an even larger source of uncertainty is people and how their consumptive patterns will change," Mankin said. "We know populations will increase and that demand will as well, but that technological and management changes could offset at least some of these increases. So there is some capacity to adapt, but that capacity is going to be different for different places."

Moreover, declining snowpacks could lead to drier forests, which in turn would face an increased fire risk during summer seasons. Food supply for birds could also decrease, while cold-water fish like trout would also face environmental threats.

"We did not know where snow was critical to supplying water for people and thus where people are most likely to be sensitive to projected snow changes," said Mankin. "Many of the basins that are currently snow-dependent have large risks of declines in snow's future potential to supply current demands given both changes in rainfall and snowpack."


Our work is licensed under Creative Commons (CC BY-NC-ND 3.0). Feel free to republish and share widely.

... We've had enough. The 1% own and operate the corporate media. They are doing everything they can to defend the status quo, squash dissent and protect the wealthy and the powerful. The Common Dreams media model is different. We cover the news that matters to the 99%. Our mission? To inform. To inspire. To ignite change for the common good. How? Nonprofit. Independent. Reader-supported. Free to read. Free to republish. Free to share. With no advertising. No paywalls. No selling of your data. Thousands of small donations fund our newsroom and allow us to continue publishing. Can you chip in? We can't do it without you. Thank you.

Critics Warn Biden 'Summit for Democracy' Will Highlight Democrats' Failures at Home

"President Biden can't champion democracy across the globe without fulfilling his promise to protect our voting rights at home."

Jessica Corbett ·


'Like a Teenager Promising to Clean Their Room in 30 Years': Biden Net-Zero Climate Goal for 2050 Ridiculed

"2050 is an extremely weak goal for the federal government to free itself from climate-heating pollution. It ignores existing technology and adds decades to GSA's own commitment to 100% renewable energy by 2025."

Brett Wilkins ·


Biden Should Cancel Student Debt or Watch $85 Billion Evaporate From US Economy: Analysis

Far-reaching cancellation enacted by Biden could add more than $173 billion to the nation's GDP in 2022 alone.

Kenny Stancil ·


Given Cover by Red-Baiting GOP, Corporate Dems Rebuked for Tanking Biden Nominee for Top Bank Regulator

"If you think that Senate Democrats rose up to [Republicans'] shameful display of modern McCarthyism by rallying around President Biden's nominee or her ideas that banking should work for the middle class, then you don't know the soul of today's Democratic Party," wrote one columnist.

Julia Conley ·


'S.O.S.!': Groups in Red States Nationwide Plead With Democrats to Pass Voting Rights Bill

"We can tell you firsthand that our Republican senators have no interest in joining this effort."

Jake Johnson ·

Support our work.

We are independent, non-profit, advertising-free and 100% reader supported.

Subscribe to our newsletter.

Quality journalism. Progressive values.
Direct to your inbox.

Subscribe to our Newsletter.


Common Dreams, Inc. Founded 1997. Registered 501(c3) Non-Profit | Privacy Policy
Common Dreams Logo