The scientists have discovered a massive cavity roughly two-thirds the size of Manhattan beneath a glacier in Antarctica. The researchers say this is a "disturbing discovery" that shows the "explosive" rate at which ice is melting on the planet's southernmost continent.
"[The size of] a cavity under a glacier plays an important role in melting," said Pietro Milillo of NASA's Jet Propulsion Laboratory in a news release by the organization. "As more heat and water get under the glacier, it melts faster."
The discovery is important, because it illustrates that Antarctic ice not only melts at the edges touching the ocean, but also from underneath ice sheets, CBS News notes. The West Antarctic ice sheet in general is considered one of the most unstable and vulnerable, the report says.
"The findings highlight the need for detailed observations of Antarctic glaciers' undersides in calculating how fast global sea levels will rise in response to climate change," the Jet Propulsion Laboratory said.
According to NASA, the cavity once contained some 14 billion tons of ice, most of which has supposedly melted in last three years. The scientists have calculated that the melting glacier has already contributed to about 4 percent of the total global sea level rise.
In the meantime, as polar ice melts, the US has been hit with anomalous low temperatures due to a polar vortex, with air temperature in Chiсago dropping below —20 degrees Fahrenheit.