When people say river, one imagines rushing water sparkling in the sunlight, however, there might be an ancient river that’s been buried underground for years and still flowing freely.
According to a team of researchers, one such hypothetical underground river exists in perpetual darkness buried under Greenland. It is fed by the melting ice in the glaciers and has been named "Dark River" by the team.
If such a river truly exists, then it is 1,000 kilometres (620 miles) long; stretching from Greenland’s deep interiors to the Petermann Fjord in the country's northwest. According to ice sheet modeller Christopher Chambers, the results of this study are consistent with a potential subglacial river but they have uncertain elements.
The uncertainty he refers to is the gap in aerial surveys and radar data of the Greenland Ice Sheet. The radar has picked images of what seems to be a very long extending stretch of subglacial river below Greenland over the years.
Some past studies have suggested that trenches or valleys or mega-canyons lie underneath the ice-covered environment. Some even suggest that liquid water flows at the bottom of all of the structures in the subglacial world. The biggest gap in knowledge is that all of the above data is fragmented.
No one has been able to confirm if these are all a part of one long river or multiple, individual structures, let alone the presence of liquid water underneath it all.
“We don't know how much water, if any, is available to flow along the valley, and if it does indeed exit at Petermann Fjord or is refrozen, or escapes the valley, along the way,” said Chambers to Science Alert.
However, Chambers and his team designed a “thought experiment” where they explore the hypothetical possibility, that it is all one great river and not fragmented parts of the valley. Their modelling suggests that it is a plausible idea.
Based on the simulation, there can be a waterway where liquid water flows uninterrupted from the centre of Greenland all the way to the sea. However, rises in the aerial view suggest they may be fragments and the team is trying to find a proper explanation for it.
The findings have been published in The Cryosphere.