NASA image shows extensive 'record level' ice coverage of the Great Lakes

NASA image shows extensive 'record level' ice coverage of the Great Lakes.HT :Weathernetwork.

Last year, ice covered about 38 per cent of the Great Lakes, which was a dramatic jump from 13 per cent in 2011-2012.

"The extreme freezing of the lakes is an unusual sight for residents, and has brought tourists flocking to certain locations, such as the Apostle Islands National Lakeshore, where Lake Superior’s thick ice has thousands trekking about one mile across the lake to visit spectacular frozen ice caves," NASA says.

The extensive ice coverage however, interferes with marine commerce, boating and fishing, all of which depend on navigable waterways.

"It also closes the lakes to migratory birds which flock here in the winter time," adds NASA.

Related:  Great Lakes ice cover reaches 20-year high.