Jim Halfpenny, U.S. Navy (Ret.), Ph.D., is an author, scientist, and educator whose interest in COLD (altitudinal, latitudinal, and seasonal) has taken him to all seven continents. He co-led the joint British American East Greenland expedition in 1975, and led the American East Greenland expedition in 1976. Jim is a Fellow of the Explorer’s Club and has received the Antarctic Service medal and Navy achievement medal with combat V. A past Research Fellow of the Institute of Arctic and Alpine Research, Jim was Director of the Mountain Research Station and the Long-Term Ecological Research program in the Alpine. As part of his ecological research, Jim personally collected air samples for the second longest atmospheric gas study in the world and developed climate change studies in the alpine. He also is a world leader in seasonal cold research—the ecology of winter. Currently, Jim is President of A Naturalist’s World, an ecological education company located at the north gate to Yellowstone National Park.