MARY LOUISE KELLY, HOST:
Climate change will cause glaciers around the world to disappear even more quickly than previously thought. But NPR's Rebecca Hersher reports slashing greenhouse gas emissions would still make a big difference.
REBECCA HERSHER, BYLINE: There are more than 200,000 glaciers in mountains around the world, and they're shrinking. But predicting how quickly that's happening has been hard because glaciers are really big and often hard to get to. David Rounce is one of the authors of a new study.
DAVID ROUNCE: In the past couple of years, there's really been a revolution in terms of the amount of data.
HERSHER: Specifically data from satellites, which allows researchers to peer into the future. And what they found is sobering. Many places are on track to lose virtually all of their glaciers by the end of the century.
ROUNCE: So areas like western Canada, the contiguous United States, the caucuses and Middle East, Central Europe, a lot of the glaciers in those mountainous regions would be lost completely.
HERSHER: In all, the new study estimates that unless emissions fall more quickly, nearly 70% of all glaciers will be gone by 2100.
ROUNCE: A lot of the glaciers are very small.
HERSHER: Which makes them more susceptible to melting, says Rounce. But...
ROUNCE: The loss of those glaciers could have a really large impact, even though they're small.
HERSHER: That's because billions of people live downstream of glaciers and use their meltwater for drinking and irrigation.
ROUNCE: Glaciers are unique in that they are there all summer long. And so even in times of extreme heat or when you have an extreme drought, the glaciers will be producing meltwater, and they can be a very important buffer in those times of drought.
HERSHER: The authors of the study also looked at what would happen if humans reduce greenhouse gas emissions faster. They found it would make a big difference. If humans can keep global warming to 1.5 degrees Celsius, the goal agreed to by world leaders, it would save an estimated 20% of the world's glaciers this century. Rebecca Hersher, NPR News. Transcript provided by NPR, Copyright NPR.