France-sized Antarctic glacier has scientists concerned – Here's why

(Representational image)

New Delhi: A giant France-sized glacier floating in the Antarctica waters has raised concerns among scientists, who revealed that there is more of the moving mass of ice than previously estimated.

Scientists fear that the glacier could melt faster as the climate warms and have a dramatic impact on the already rising sea-levels.

One of the fastest-flowing and largest glaciers in Antarctica, the Totten Glacier, could potentially unleash an enormous amount of water and scientists are keen to keep a close eye on its melting pattern.

Using artificially created seismic waves that help scientists see through the ice, researchers have discovered that more of the Totten Glacier floats on the ocean than initially thought.

"In some locations, we thought were grounded, we detected the ocean below indicating that the glacier is in fact floating," said Paul Winberry from Central Washington University, who spent the summer in Antarctica studying the Totten.

The findings are important because recent studies have shown the Totten Glacier's underbelly is already being eroded by warm, salty sea water flowing hundreds of kilometers inland after passing through underwater "gateways".

As it does, the portion of the glacier resting on water rather than rock increases, accelerating the pace of disintegration.

Winberry said more of the glacier floating on a warming ocean could help explain recent periods of accelerated melting.

"It also means the Totten might be more sensitive to climate variations in the future," he added.

Glaciers are huge bodies of dense ice that slowly move down valleys, mountains, and slopes under their own weight over many centuries, sculpting the earth below as they go.

They hold the vast majority of Earth's freshwater and are the main contributor to rising sea levels when they melt.

According to NASA monitoring, between 2002 and 2016, Antarctica lost 125 gigatonnes of ice per year, causing sea levels worldwide to rise by 0.35 millimeters annually.

From the air, the contours of Totten Glacier are invisible because the entire Antarctic continent is covered by a seamless, kilometers-thick blanket of snow and ice.

That is why scientists are so determined to understand what is happening underneath the glacier, hidden from view.

Team leader Ben Galton-Fenzi, from the Australian Antarctic Division, said the Totten Glacier contains enough ice to raise global sea levels by about three meters (9.8 feet) if it all melted.

"Since the 1900s the global sea-level has risen by around 20 centimeters and by the end of the century it's projected to rise by up to one meter or more, but this is subject to high uncertainty which is why studying glaciers such as the Totten is important," he said.

"These precise measurements of Totten Glacier are vital to monitoring changes and understanding them in the context of natural variations, and the research is an important step in assessing the potential impact on sea-level under various future scenarios."

Instruments to measure the glacial flow, speed and thickness have been left on the glacier for another 12 months collecting data.

(With PTI inputs)