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The annual glaciohydrology cycle in the ablation zone of the greenland ice sheet: part 2. observed and modeled ice flow
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Anderson, Robert S. Zwally, H. Jay Abdalati, Waleed Phillips Sr., Thomas Colgan, William Terence Rajaram, Harihar Steffen, Konrad |
| Copyright Year | 2012 |
| Description | Ice velocities observed in 2005/06 at three GPS stations along the Sermeq Avannarleq flowline, West Greenland, are used to characterize an observed annual velocity cycle. We attempt to reproduce this annual ice velocity cycle using a 1-D ice-flow model with longitudinal stresses coupled to a 1-D hydrology model that governs an empirical basal sliding rule. Seasonal basal sliding velocity is parameterized as a perturbation of prescribed winter sliding velocity that is proportional to the rate of change of glacier water storage. The coupled model reproduces the broad features of the annual basal sliding cycle observed along this flowline, namely a summer speed-up event followed by a fall slowdown event. We also evaluate the hypothesis that the observed annual velocity cycle is due to the annual calving cycle at the terminus. We demonstrate that the ice acceleration due to a catastrophic calving event takes an order of magnitude longer to reach CU/ETH ('Swiss') Camp (46km upstream of the terminus) than is observed. The seasonal acceleration observed at Swiss Camp is therefore unlikely to be the result of velocity perturbations propagated upstream via longitudinal coupling. Instead we interpret this velocity cycle to reflect the local history of glacier water balance. |
| File Size | 764230 |
| Page Count | 14 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20140008938 |
| Archival Resource Key | ark:/13960/t6159km5d |
| Language | English |
| Publisher Date | 2012-02-15 |
| Access Restriction | Open |
| Subject Keyword | Ice Flow Greenland Ice Sheet Modeled Ice Flow Thermodynamics Hydrological Cycle Elevation One Dimensional Flow Flow Distribution Mathematical Models Ice Glaciers Water Balance Ablation Greenland Hydrology Models Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
