Water Discharge and Cirque Glacier Hydrology at West Washmawapta Glacier, British Columbia, Canada
Abstract
Cirque glaciers are small bodies of ice that do significant geomorphic work at high elevations in alpine landscapes. As part of a larger project investigating West Washmawapta Glacier (WWG) in British Columbia, this study explores englacial, subglacial, and proglacial hydrology. WWG has a complex proglacial zone with at least two outlet streams, a series of small proglacial lakes, and contributions from the nearby Washmawapta Icefield. In summer 2007 we used a series of salt tracer dilution experiments to constrain water discharge at three locations in the proglacial hydrologic system. Salt discharge measurements were conducted every hour at a glacier outlet stream and at the two stream gages in order to directly measure diurnal variability in discharge at each location. Measurements of water discharge were used to construct rating curves for two locations in the proglacial system. Water discharge from WWG joins with meltwater runoff from Washmawapta Icefield, and stream gauges were established upstream and downstream of water input from WWG to isolate water discharge from WWG. Rating curves allowed for the calculation of discharge continuously throughout the field season at both stream gauges. From this data, the discharge from WWG could be determined. Analysis of this signal showed four distinct periods based on the diurnal cycle. Calculations of surface melt flux, stream flux, and examination of the relationship between water discharge and air temperature demonstrated that these periods were a consequence of development of either englacial or subglacial water transport systems. Incorporation of this data with other field observations revealed that there were likely two independent glacial hydrologic systems, one of which showed increased ability to transport melt to the proglacial system over the field season.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2008
- Bibcode:
- 2008AGUFM.H51D0831T
- Keywords:
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- 0720 Glaciers;
- 1860 Streamflow;
- 1862 Sediment transport (4558);
- 1876 Water budgets;
- 1895 Instruments and techniques: monitoring