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 watershed s within the Kuparuk River basin in northern Alaska as part of an inte rdisciplinary effort to quantify the flux of mass and energy from a la rge arctic area. Described here are characteristics of annual hydrogra phs and individual storm hydrographs of four basins draining areas of 0.026 km(2), 2.2 km(2), 142 km(2), and 8140 km(2); an assessment of th e influence that permafrost has on those characteristics; and comparis ons to rivers in regions without permafrost. Snowmelt runoff dominated the annual runoff in each basin. A typical storm hydrograph in the Ku paruk River basin had a fast initial response time, long time lags bet ween the hyetograph and hydrograph centroids, an extended recession, a nd a high runoff/precipitation ratio due to the diminished storage cau sed by permafrost. The seemingly contradictory results of fast respons e times and extended recessions can be explained by the presence of a large saturated area occupied by hillslope water tracks. This saturate d area provides a partial-source area for fast runoff generation that bypasses the storage capacity of organic soils and tundra vegetation. (C) 1998 Elsevier Science B.V. All rights reserved.