The shipping vessels that transport goods on Lake Superior in the winter months face many challenges. As the water temperature cools below the -10°F (-23°C) air above, sea smoke forms over the Great Lake due to evaporative cooling. This is one of my favorite winter phenomena, and is a welcome reward for braving the bitter temperatures and biting breezes. In addition to the reduced visibility created by this winter fog, it coats the ships' surfaces with ice. Crews face the challenge of clearing the ice from the vessels with sledgehammers, so it does not impede the ships' maneuverability. It is amazing to see these "thousand-footers" emerge through the graceful sea smoke while cloaked in thick ice.