Disappeared in one year – how a lake the size of France changed the Earth

The article tells about Lake Agassiz, a giant body of water covering more than 440,000 km² that existed in North America about 16,000 years ago. It disappeared around 8,400 years ago when ice barriers collapsed and water drained into the ocean, potentially raising sea levels by 2.8 meters and causing a sharp cold snap — the Younger Dryas.

The article describes the history of Lake Agassiz, a giant glacial reservoir that existed in North America. The lake formed about 16,000 years ago when the retreating Laurentide Ice Sheet blocked the natural drainage of meltwater. Its area reached approximately 440,000 square kilometers, exceeding the area of modern France. Over time, the ice barriers broke down and the direction of water flow changed. One of the largest discharges occurred through the Hudson Bay region, when a huge volume of fresh water entered the Arctic and Atlantic Oceans. Scientists link this event to significant climate changes: a warming period was replaced by a sharp cold snap known as the Younger Dryas, which lasted about 1,200 years. Temperatures in the Northern Hemisphere dropped by about 3 degrees. During this period, a number of megafauna species disappeared in North America, including mammoths, giant sloths, and saber-toothed predators. The last major stage of the lake's existence occurred about 8,400 years ago, when water rapidly drained into the ocean, potentially raising global sea levels by about 2.8 meters within a year. The lake bed formed vast plains that today constitute the Canadian prairies and parts of the US Midwest. Modern lakes Winnipeg, Winnipegosis, Lake of the Woods, and Manitoba are considered surviving fragments of the ancient water system.