Arctic shock: ‘Dark river’ 1000 MILES LONG is flowing beneath Greenland

Christopher Chambers, a researcher at Hokkaido University in Sapporo, Japan, said: “Eventually if you get it deep enough — minus 500 meters [1,640 feet] — the water is now flowing the entire length along the valley and then exiting at Petermann Fjord.”

The ice covering Greenland is up to three kilometres thick in certain places, covering an area seven times the amount of the UK.

If all of this ice were to melt, sea levels could rise by a staggering 7.4 metres around the planet, which would be catastrophic, dislodging millions of people from their homes.

A joint study from NASA and the European Space Agency (ESA), which analysed satellite date to determine the loss of ice on Greenland, found just how quickly ice is melting as a result of climate change.