Quantifying snowmelt inputs in an alpine watershed for the purpose of investigating the role of groundwater storage

Date
2013-01-30
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Abstract
Mountain headwaters contribute a greater amount of water to streamflow in Western Canada, relative to their area than lowland areas. Despite this, there is poor understanding of the source water contributions to late summer streamflow and how streamflow may be affected by increases in temperature and changes in precipitation patterns. This study used a water balance approach to study the sources of late summer streamflow and quantify groundwater storage in the Opabin watershed, a high alpine site within Yoho National Park, British Columbia, Canada. Field observations input into the water balance included stream discharge measurements, snow depth and density data, spatially distributed precipitation and on-site meteorological data. Snowmelt contributions to the water balance were quantified using a spatially distributed energy balance model (Utah Energy Balance Model). Spatially distributed incoming shortwave radiation was modeled using ArcGIS Solar Analyst. End-of-winter snow accumulation was quantified using a combination of interpolated field measurements and SWE reconstruction. The snowmelt modeling portion of this study included an assessment of the dominant controls on spatial melt rates in this watershed. Incoming has a greater influence than spatially variable SWE in controlling melt rates in this watershed, and this is attributed to the large gradients in incoming solar radiation. The water balance for two years indicates that annual groundwater storage in the watershed was 8-10% of the annual water balance. However, groundwater contributions during August and September were a substantial component of streamflow, as ascertained by a greater proportion of discharge relative to hydrologic inputs during those months. Linear reservoir modeling results and analysis of the time of concentration indicate that the response time during peak flows is on the order of several days. Response time during late summer and fall is approximately 14 days, as quantified using master recession curve analyses. This work contributes to the understanding of the relative contributions of hydrologic input sources to late summer streamflow in alpine regions.
Description
Keywords
Hydrology, Physical Geography
Citation
Hood, J. L. (2013). Quantifying snowmelt inputs in an alpine watershed for the purpose of investigating the role of groundwater storage (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/27499