Spatial variance of snowmelt as a continental alpine site

TitleSpatial variance of snowmelt as a continental alpine site
Publication TypeConference Proceedings
Year of Conference1996
AuthorsRikkers, M., Williams M. W., and Sommerfeld R.
Conference Name64th Annual Western Snow Conference
Series TitleProceedings of the 64th Annual Western Snow Conference
Date PublishedApril 1996
PublisherWestern Snow Conference
Conference LocationBend, Oregon
KeywordsColorado, Lysimeters, Niwot Ridge, Subnivean

We evaluated the spatial variance of snowmelt discharge during the 1995 melt season. We tested two hypotheses at Niwot Ridge, a continental alpine site located in the Colorado Front Range at an elevation of 3500 m: 1) meltwater discharge through snow is positively correlated at the scale of approximately 5 m, and 2) this characteristic lag distance will increase with time throughout the snowmelt season. In 1994, 16 small snowmelt lysimeters (each 0.2 m2 in area) were placed in a circular array with a 5 m radius; lysimeters were separated by a distance of 2 m along the circumference of the circle and drained by gravity into dedicated tip- ping buckets housed in a subnivean laboratory .The spatial variability in meltwater flux was large, with three tipping buckets over-topped during most of the snowmelt season, three tipping buckets receiving less than 5% of measured snow-water equivalence (SWE), and the remainder of the lysimeters showing a strong diurnal hydrograph. Not all hydrographs returned to near zero at night, in part because of a positive sensible heat flux. Analysis of the spatial variability of meltwater flux using geostatistics show positive correlations at distances of less than 6.5 m for the entire snowmelt cycle. This characteristic distance increased throughout most of the snowmelt season, from 2 mat the beginning of melt to 10 mat the end of the season.