Journal of Hydrology E L S E V I E R Journal of Hydrology 206 (1998) 39-57 An analysis of streamflow hydrology in the Kuparuk River Basin, Arctic Alaska: a nested watershed approach James P. McNamara*, Douglas L. Kane, Larry D. Hinzman Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK 99775, USA Received 15 October 1996; accepted 4 December 1997 Abstract 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 km 2, 2.2 km 2, 142 km 2, 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. © 1998 Elsevier Science B.V. All rights reserved. Keywords: Alaska; Arctic; Permafrost; Runoff; Streamflow 1. Introduction The shape of a hydrograph reflects how a drainage basin transforms precipitation into runoff and embodies the integrated influence of several basin characteristics including the geology, soils, drainage- basin morphology, and vegetation. Hence, the quanti- tative description of hydrographs is a valuable tool for understanding the mechanisms by which the drainage basin controls hydrology, and offers a tool for com- paring hydrologic characteristics between different physiographic regions. * Corresponding author. Department of Geosciences, Boise State University, Boise, ID, 83725, USA. E-mail: jmcnamar@bsu. idbsu.edu 0022-1694/98/$19.00 © 1998 Elsevier Science B.V. All rights reserved. PII S0022- 1694(98)00083-3 The ubiquitous presence of permafrost is a domi- nant physical characteristic of all arctic basins. Several studies have shown that permafrost has significant influences on streamflow characteristics (Church, 1974; Dingman, 1970, 1973; Kane et al., 1989; New- bury, 1974; Slaughter and Kane, 1979; Slaughter et al., 1983; Woo and Steer, 1982, 1983). However, the database for watersheds in regions with permafrost is still sparse. An interdisciplinary effort called the Land-Air-Ice Interaction (LAII) Flux Study was initiated in 1993 to estimate the flux of mass and energy between the land, atmosphere, and the Arctic Ocean in the Kuparuk River basin in Northern Alaska (Weller et al., 1995). River discharge is a major export mechanism of mass and energy out of any drainage basin. Thus, we implemented a nested watershed