Quiescent-phase dynamics and surge history of a polythermal glacier: Hessbreen, Svalbard
Abstract:Hessbreen is a 5 km2, polythermal glacier in southern Spitsbergen. It is believed to have surged at the end of the 19th century, and another surge started in 1969, not in 1972 as earlier studies suggested. The surge was probably triggered in the middle section of the glacier and affected the upper part approximately 4 years before including the whole glacier. Present velocities are low, increasing from 0.3 m a−1 at the snout to 4.8 m a−1 above the equilibrium line. A distinct velocity reduction occurs where the glacier narrows. This suggests the velocities here are affected by the cold marginal and frontal ice. Large seasonal variations, with summer velocities of more than twice the winter velocities in the middle part of the glacier, indicate a seasonal change in the drainage system in this area. In the lower part there is no apparent sliding. The balance-flux estimate indicates that the actual ice flux is only about 50% of that required for steady state, so Hessbreen appears to be building up in the accumulation area. The surge duration is now estimated to be 8 years.
Document Type: Research Article
Publication date: December 1, 2004
More about this publication?
- The Journal of Glaciology is published six times per year. It accepts submissions from any discipline related to the study of snow and ice. All articles are peer reviewed. The Journal is included in the ISI Science Citation Index.
- Editorial Board
- Information for Authors
- Ingenta Connect is not responsible for the content or availability of external websites