Greenland Lake empties in ninety minutes

A report in the highly prestigious journal, Science, says that researchers have recorded the drainage from a lake in Greenland that was so rapid that it drained in less than ninety minutes. WHOI glaciologist Sarah Das said that the lake had been approximately 5.6 km2.

The water from the lake drained from the base of an ice sheet that that had been holding the fresh water back from the sea. The drain was 980 m below the surface of the lake. Although the lake actually took a full twenty four hours to empty, the vast majority of the water was lost in just one and a half hours.

During this brief ninety minute period 8700 cubic meters per second gushed out of the bottom of the glacier. If you have difficulty picturing how much that is, imagine the might of Niagara Falls, which only flows at 5700 cubic meters per second.

For the first few hours the scientists observed only a slow drop in the lake water level, then after 16 hours, the water dropped at an alarming rate. They believe the reason for this was that the fracture in the base of the glacier suddenly cracked wide open. Allowing the massive volume of water to drop out of the bottom of the lake suddenly, like a cracked damn, collapsing.