A massive outburst flood from a Canadian glacial lake during the last interglacial period transported sediment across the Labrador Sea in the North Atlantic, reports a paper published online this week in Nature Geoscience. This event seems to be analogous to a similar outburst flood that occurred about 8,400 years ago and caused cooling across the Northern Hemisphere.

Joseph Nicholl and colleagues examined marine sediments from the Labrador Sea, deposited during the last interglacial, between 125,000 and 119,000 years ago. They identified an unusual red layer of sediments derived from the Hudson Bay. These red sediments were most likely deposited during a massive outpouring of water from a continental lake that was filled by the melting North American ice sheet. The flood layer proved difficult to date, but the authors suggest that it may correspond to a period of cooling previously identified in the North Atlantic.