Coast Guard Cutters Shackle and Tackle break ice and create sea smoke along the Penobscot River in Brewer, Maine, Feb. 11, 2014. Both 65-foot cutters broke through the nearly 20-inch thick ice to allow open water to flow. Sea smoke is formed when the water temperature is much warmer than the surrounding air. (U.S. Coast Guard photo by Petty Officer 2nd Class Rob Simpson)