Air temperatures internal and external to a talus cave (‘ice mine’) in central Pennsylvania were measured hourly for three years. Despite its location near the base of a talus slope, the cave demonstrated the thermal characteristics of an apparently static cave, with limited connections to the external environment other than through the cave entrance. Congelation ice that lasted until late spring formed as drip or flowstone and ponded ice from the limited influx of infiltrating water during late winter/early spring. A closed period of thermal stratification and slow warming of cave air was followed by an open period in winter months during which the cave was cooled by the influx of cold dry air. Unlike the occasionally strong and localised cooling induced by the flow of cold air from vents at the base of talus slopes, static cold traps retain their cold air and have little apparent effect on surrounding biota, instead providing potential refugia for organisms that prefer colder temperatures. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.