Deep-ice temperature measurements have been made in two surge-type glaciers in the Yukon Territory, Canada. Cold ice warming towards the bed was found in Trapridge Glacier and a model of basal ice temperatures predicts large regions of basal temperate ice. Thermal regulation of the surge behavior of this small glacier is inferred; theoretical considerations show that this hypothesis can reasonably be extended to large surging glaciers as well. Temperatures below 0°C were also recorded on Steele Glacier. An anomalously warm layer was detected at a depth of approximately 50 m. This is attributed to the severe crevassing associated with a glacier surge. Numerical modelling of the effects of water-filled crevasses in a cold glacier, refreezing and injecting latent heat into the ice, predicts temperature profiles very similar to that observed. The model further predicts long term maintenance of the resulting trapped water pockets and, in small surging glaciers, a thermal memory of the initial crevassing throughout the entire quiescent phase.
