Networks of lakes, streams found on Antarctica's surface: Study

Scientists have found that vast lakes and streams are widespread on the surface of Antarctica's ice sheets which may accelerate its contribution to the rise in sea-level, a new study suggests.

"Our study has found that extensive networks of lakes and streams have persisted in Antarctica for decades which move surface water across its ice sheets onto ice shelves," said Jeremy Ely from University of Sheffield in the UK.

Researchers from the University of Sheffield used aerial photography and satellite imagery to find that melt-water moves vast distances across the surface of the ice sheets onto ice shelves.

Huge lakes have been forming on the surface of Antarctica since at least the 1940s and extensive networks of streams have been draining water onto vulnerable ice shelves that are prone to collapse, researchers said.

Scientists previously believed that the drainage of surface water, known as melt-water, was a rarity in Antarctica.

Ice shelves, which are floating parts of ice sheets, are prone to collapse when water flows into their cracks and crevasses, they said.

"If melted completely, Antarctica's ice sheets contain enough water to raise global sea levels by around 58 metres, so it is important that we understand how and where melt-water forms, moves, drains and the impact it can have on ice shelves, which can be prone to collapse," Ely said.

The research team believes that in a warming climate, more water is likely to be produced on the surface of Antarctica, which could accelerate the ice sheets' contribution to sea level rise.

Current predictions of sea-level rise do not include these processes.

"Despite extensive studies in Greenland and observations of individual melt-water drainage systems in Antarctica, we previously had little understanding of how water moves across the surface of Antarctica s ice sheets," Ely said.

The study was published in the journal Nature.