'World's most dangerous glacier' to collapse and it could rise global sea levels by 8 feet

Washington, Feb 04: A large cavity has formed under one of the world's most dangerous glacier, and is teetering on the verge of collapse, threatening to raise global sea levels by an unprecedented eight feet.

Nasa has discovered a gigantic cavity which is about two-thirds the area of Manhattan and roughly 1,000 feet tall which is growing under Thwaites Glacier in West Antarctica.

The cavity is large enough to have contained 14 billion tons of ice, most of which has melted within the last three years, say researchers.

The ice mass has been dubbed the "world's most dangerous glacier" because it holds enough ice to raise the world oceans more than two feet (65cm).

The gigantic Thwaites glacier covers around 113,000 square miles - about half the area of the United Kingdom.

If it melts, global sea levels will rise by over 2 feet, causing coastal flooding that will turf hundreds of thousands of people across the globe from their homes.

The cavity was revealed by ice-penetrating radar in NASA's Operation IceBridge, an airborne campaign beginning in 2010 that studies connections between the polar regions and the global climate.

Last year, the National Science Foundation and Britain's Natural Environment Research Council launched a joint program called the International Thwaites Glacier Collaboration to study the unstable glacier and its role in sea levels.