Unprecedented amount of ice still present at Great Lakes, USA/Canada
Apr 25, 2014
Although North America is now a full month into astronomical spring, the Great Lakes are still almost half frozen. As of April 22, 2014, the Great Lakes were 33.9 percent ice covered. Some scientists say that the amount of ice that still remains could have a big impact on the environment in the months and years ahead.
- Lake Superior is the world’s largest freshwater lake by area (82,100 square kilometers or 31,700 square miles) and the third largest by volume. The waters average 147 meters (483 feet) in depth, and the basin is believed to hold about 10 percent of the world’s liquid fresh water.
- Lake Superior had 3.6 percent ice cover on April 20, 2013; in 2012, ice was completely gone by April 12.
- In the last winter that ice cover grew so thick on Lake Superior (2009), it reached 93.7 percent on March 2 but was down to 6.7 percent by April 21.
In the early afternoon on April 20, 2014, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this natural-color image of Lake Superior, which straddles the United States – Canada border. At the time Aqua passed over, the lake was 63.5 percent ice covered, according to the NOAA Great Lakes Environmental Research Lab (GLERL). Averaged across Lake Superior, ice was 22.6 centimeters (8.9 inches) thick; it was as much as twice that thickness in some locations.