Earth Observatory Science Earth Observatory Farming in Ancient Lake Agassiz Earth Earth Observatory Image of the Day EO Explorer Topics All Topics Atmosphere Land Heat & Radiation Life on Earth Human Dimensions Natural Events Oceans Remote Sensing Technology Snow & Ice Water More Content Collections Global Maps World of Change Articles Notes from the Field Blog Earth Matters Blog Blue Marble: Next Generation EO Kids Mission: Biomes About About Us Subscribe 🛜 RSS Contact Us Search  Editor’s Note: Today’s story is the answer to the May Puzzler.About 15,000 years ago, southeastern Manitoba sat beneath tens of meters of frigid water. Lake Agassiz—which once encompassed present-day Lake Manitoba, Lake Winnipeg, and Lake of the Woods—covered an area larger than all of the Great Lakes combined. It formed in front of the retreating Laurentide Ice Sheet, which dammed rivers that otherwise might have drained into Hudson Bay, producing an expansive body of water 1,100 kilometers (700 miles) long by 300 kilometers wide that spanned parts of today’s Manitoba, Ontario, Saskatchewan, North Dakota, and Minnesota. The lake began draining roughly 12,000 years ago, but its legacy remains visible across the region. In April 2026, an astronaut aboard the International Space Station snapped…
Technical
Farming in Ancient Lake Agassiz
Source: NASA JPL — US Government, Public Domain