An analysis of streamflow hydrology in the Kuparuk River Basin, Arctic Alaska: A nested watershed approach

A hydrologic monitoring program was implemented in a nest of watersheds within the Kuparuk River basin in northern Alaska as part of an interdisciplinary effort to quantify the flux of mass and energy from a large arctic area. Described here are characteristics of annual hydrographs and individual storm hydrographs of four basins draining areas of 0.026 km², 2.2 km², 142 km², and 8140 km²; an assessment of the influence that permafrost has on those characteristics; and comparisons to rivers in regions without permafrost. Snowmelt runoff dominated the annual runoff in each basin. A typical storm hydrograph in the Kuparuk River basin had a fast initial response time, long time lags between the hyetograph and hydrograph centroids, an extended recession, and a high runoff/precipitation ratio due to the diminished storage caused by permafrost. The seemingly contradictory results of fast response times and extended recessions can be explained by the presence of a large saturated area occupied by hillslope water tracks. This saturated area provides a partial-source area for fast runoff generation that bypasses the storage capacity of organic soils and tundra vegetation.