The Coast Guard Cutter Alder breaks a path through the ice in the Keweenaw Waterway near Houghton, Mich., Dec. 16, 2016. The Alder and other Great Lakes Coast Guard cutters commenced Operation Taconite, the Coast Guard’s largest domestic ice-breaking operation, encompassing Lake Superior, the St. Mary’s River, the Straits of Mackinac and Lake Michigan, Dec. 19, 2016. (U.S. Coast Guard photo)