The Operational Land Imager on the Landsat 8 satellite captured the top image on May 23, 2014, the start of Memorial Day weekend (and unofficial start of summer in the United States). The second image was acquired on June 8, 2014. Both show an icy Lake Superior near Chequamegon Bay, Wis., about 60 miles (100 kilometers) east of Duluth, Minn. The bay lies near the western end of Lake Superior, which is bounded by the U.S. states of Wisconsin, Michigan and Minnesota and by Canada's Ontario Province.
Air temperatures in the states and provinces around the Great Lakes suggest that meteorological summer has arrived. But the icy grip of winter is lingering in cool water temperatures and drifting chunks of ice.
For nearly seven months, ice has been afloat somewhere on the Great Lakes, an ice season longer than any in Earth observation satellite records or anyone's memory. In an average year, the lakes are ice free by late April or early May.
As recently as May 20, 2014, Lake Superior was nearly
7 percent ice covered; on June 3, it was 1.3 percent”even as air temperatures onshore approached 80 degrees Fahrenheit (27 degrees Celsius) on some days. In the second week of June, boaters, fishermen and scientists were still capturing photos of ice chunks in the water, although the Great Lakes Environmental Research Laboratory officially declared the region to be effectively ice free for the sake of shipping interests.
Lake Superior's residual ice in June isn't necessarily a surprise given the record-setting cold weather and extensive ice cover this winter. The Weather Channel reported that temperatures in nearby Marquette, Wis., stayed below freezing for a record 75 days last winter. Lake Superior was still 64 percent ice-covered in mid-April 2014. And water temperatures in Lake Superior were still in the 30s (0 to 5 Celsius) as of
June 10, 2014.
