This red oak leaf was found locked in ice near Mackinaw City, Michigan , on frozen Lake Huron . The leaf, left over from last fall, perhaps blew onto the lake just after the snow had melted but before the ice had begun to melt. Due to its relatively low albedo , the leaf absorbs more of the Sun's energy than the surrounding ice and locally warms the area beneath it. As the leaf melts down into the ice, it leaves the distinct shape of its delicate structure, creating a beautiful and unique impression. Photo taken on March 16, 2015.