Call number:
ZSP-202-297
In:
Research report
Description / Table of Contents:
CONTENTS: Preface. - Abstract. - Introduction. - Glenn Creek watershed. - Location. - Topography. - Geology, soils and permafrost. - Climate. - Vegetation. - Data collection. - Precipitation. - Stream flow. - Air temperature and relative humidity. - Water temperature. - Evaporation. - Snow surveys. - Depth of thaw. - Dissolved solids. - Hydrology. - Introduction. - General channel description. - Hydraulic geometry. - Characteristics of hydrographs. - Sources of streamflow. - Attempts at flow separation. - Hydrograph modeling. - Summary and conclusions. - Literature cited. - Appendix A: Summary of permafrost probe observations, Glenn Creek watershed.. - Appendix B: Water-holding and-transmitting properties of moss. - Appendix C: Summary of hydraulic geometry data from 1964 discharge measurements. - Appendix D: Summary of data used in computing recession constants.
Description / Table of Contents:
The results of a four-summer (1964-1967) hydrologic study of the watershed of Glenn Creek, about 8 miles north of Fairbanks, Alaska, in the Yukon-Tanana uplands physiographic province, are presented. This work was initiated to provide initial baseline hydrologic data for a small subar ctic watershed, the first of its kind in North America. Standard hydrologic and meteorologic instrumentation was used, and streamflow characteristics were analyzed by standard hydrograph-analysis techniques. The stream is second-order, and drains an area of 0.70 square mile. Basin elevations are from 842 ft to 1618 ft. In regard to topography, geology, soils, permafrost, vegetation, and climate, the watershed seems to be representative of low-order, low-elevation drainage basins in the province. Analysis of rainfall-runoff data indicates that about half the 12.3-in. normal annual precipitation is runoff. The remainder is the actual evapotranspiration , which equals only about 30% of estimated potential evapotranspiration. For individual storms, runoff/rainfall proportions were from 0.03 to 0.42 and were positively correlated with antecedent discharge of the stream, which is a measure of watershed wetness. The stream responds rapidly to rainstorms except when the basin is very dry, and has markedly slow recessions compared with temperate region streams of similar size. Rate of recessions is apparentlv controlled by concurrent evapotranspiration rates. Analysis of hydrographs and knowledge of the physical characteristics of the basin indicate that storm runoff occurs initially as surface runoff from bare soil areas adjacent to the stream, while recessions are dominated by a combination of tunnel flow beneath moss-covered parts of the basins and typical groundwater flow through the moss and soils. Peak discharges for individual storms could be well estimated by an equation including antecedent discharge, total precipitation and storm duration, and average recession constant. These results represent the first detailed hydrologic data from the discontinuous permafrost zone of the North American taiga and should be of significance to the International Hydrological Decade and International Biological Program.
Type of Medium:
Series available for loan
Pages:
vi, 111 Seiten
,
Illustrationen
Series Statement:
Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 297
URL:
http://www.worldcat.org/oclc/3282990
Language:
English
Branch Library:
AWI Library
