In a study published in Science, the scientists analysed thousands of kilometres of airborne radar data, collected over several decades, to piece together a map of the landscape lying beneath the Greenland ice sheet. The analysis revealed a continuous bedrock canyon that extends from almost the centre of the island and ends beneath the Petermann Glacier fjord in northern Greenland.
‘One might assume that the landscape of the Earth has been fully explored and mapped,’ said the study’s lead author, Jonathan Bamber of the University of Bristol. ‘Our research shows there’s still a lot left to discover.’
The canyon, which is thought to predate the ice sheet that has covered Greenland for the last few million years, has the characteristics of a winding river channel. It’s at least 750 kilometres long, making it longer than the Grand Canyon, and in some places is as deep as 800 metres.
Evidence suggests that the canyon once comprised a major river system, with water flowing through it from the interior of Greenland to the coast. The researchers believe that it now plays an important role in transporting sub-glacial meltwater.
This story was published in the October 2013 edition of Geographical Magazine