Greenland glaciers melting 3 times faster than 20th Century: Study

New Delhi: Greenland glaciers and ice caps are melting three times faster since the start of the 20th century, a study has found.

The study, published in the journal Geophysical Research Letters, provides critical insights into long-term changes to the Greenland glaciers and ice caps as a result of climate change, which has contributed about one fifth to global sea-level rise in the last decade.

Using historical data, scientists mapped 5,327 glaciers and ice caps that existed at the end of the Little Ice Age in 1900; a period of wide-spread cooling when average global temperatures dropped by as much as 2 degrees Celsius.

The study found that Greenland's glaciers have lost at least 587 cubic kilometres (km3) of ice over the last century, accounting for 1.38 millimetres of sea-level rise. That equates to 499 gigatonnes (Gt) at an alarming rate of 4.34 Gt per year.

It estimates the speed at which the water melted between 2000 and 2019 was three times higher than the long-term (since 1900) average.

"Seeing how glaciers have evolved over a longer period of time can give us a better chance of predicting how they will change in the future," said Clare Boston from the University of Portsmouth, UK.

Previous research using satellite data suggests Greenland's glaciers and ice caps could lose between 19 per cent and 28 per cent of their volume by 2100.

"These predictions only use information gathered from the past few decades, whereas our research provides baseline data from more than 100 years ago," said study co-author Clare Boston from the University of Portsmouth.

"Seeing how glaciers have evolved over a longer period of time can give us a better chance of predicting how they will change in the future," Boston said.

The researchers noted that the impact of meltwater runoff from Greenland into the North Atlantic extends beyond global sea-level rise, affecting North Atlantic ocean circulation, European climate patterns, and Greenlandic fjord water quality and marine ecosystems.

"This has immense implications on humans too, with these glacier changes having a direct impact on the economic activities of fishing, mining, and hydropower, as well as affecting people's health and behaviour," said study lead author, Jonathan L. Carrivick from the University of Leeds, UK.

The research also emphasises the complex nature of glacier evolution due to considerable differences in locations, temperatures, and the influence of regional and local factors, according to the researchers.

Glaciers in the North region have experienced the greatest speed up in rate of mass loss compared to other regions while those terminating in lakes have increased the most in their rate of mass loss, they added.