Himalayan glaciers are melting at twice the rate since the start of the 21st century, and rising temperatures are the reason, according to a 2019 study.
The Himalayas are losing more than a vertical foot-and-half of ice each year due to climate change, potentially threatening water supply for hundreds of millions of people in countries, including India, the study said.
The analysis spans 40 years of satellite observations across India, China, Nepal and Bhutan. It indicates that climate change is having an adverse effect on the Himalayan glaciers, researchers said.
The study, published in the journal Science Advances in June 2019, shows that glaciers have been losing the equivalent of more than a vertical foot-and-half of ice each year since 2000 – double the amount of melting that took place from 1975 to 2000.
“This is the clearest picture yet of how fast Himalayan glaciers are melting over this time interval, and why,” said Joshua Maurer, a PhD candidate at Columbia University in the US.
The glaciers may have lost as much as a quarter of their mass over the last four decades, said Maurer, the study’s lead author.
The melting is consistent in time and space, and rising temperatures are to blame, the researchers said. Temperatures vary from place to place, but from 2000 to 2016 they have averaged one degree Celsius higher than those from 1975 to 2000, they said.