These formations were found after extensive ice penetrating radar data collected in Antarctica as part of the European Space Agency PolarGAP project. The team, led by researchers from Northumbria University in the UK, has mapped for the first time three vast, subglacial valleys in West Antarctica. These valleys could be important in future as they help to channel the flow of ice from the centre of the continent towards the coast.
If climate change causes the ice sheet to thin, these troughs could increase the speed at which ice flows from the centre of Antarctica to the sea, raising global sea levels.
The findings which are published in the journal Geophysical Research Letters, Although there are extensive satellite data that help image the surface of the Earth and its deep interior, there was a gap around the South Pole area, which is not covered by satellites due the inclination of their orbits. The PolarGAP project was therefore designed to fill in the gap in the satellite data coverage of the South Pole and in particular acquire the missing gravity data. Airborne radar data were also collected to enable mapping of the bedrock topography hidden beneath the ice sheet. The data reveals the topography which controls how quickly ice flows between the East and West Antarctic ice sheets.
The largest valley, known as the Foundation Trough, is more than 350 kilometres long and 35 kilometres wide. Its length is equivalent to the distance from London to Manchester, while its width amounts to more than one and a half times the length of New York’s Manhattan Island.
The two other troughs are equally vast. The Patuxent Trough is more than 300 kilometres long and over 15 kilometres wide, while the Offset Rift Basin is 150 kilometres long and 30 kilometres wide.