Feb 4, 2019
NASA recently announced the discovery of a cavity about 1000 feet high, covering an area about two-thirds the size of Manhattan, that has developed under the top of the ice in the Thwaites Glacier in Antarctica. They think this cavity developed in just the last three years.
Researchers have expected for some time that there were melted-out holes at the bottom of the glacier where it rests on bedrock. But the size and rapid growth rate of this cavity has shocked them. They now estimate that the roughly 14 billion tons of melted ice from this cavity and other melting of the Thwaites Glacier account for 4 percent of all the global sea level rise that has occurred so far.
But the entire Thwaites Glacier is the about the size of Florida. If this glacier melts entirely as global warming continues, it will cause an increase in world sea levels of about 2 feet. And if other ice sheets that this glacier now blocks slide into the sea, an additional 8 feet of global sea level rise will result. This would cause a catastrophe for humanity. Researchers are now warning that this could happen within our lifetimes.
The big cavity in the Thwaites Glacier was revealed using ice-penetrating radar mounted on planes flying over the glacier, supplemented by data from German and Italian satellites. Luckily, U.S. and British research organizations are about to begin a five-year study to answer questions about the Thwaites Glacier.
We shall see what they discover.