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Dennis Trabant

Publications and source records attributed to Dennis Trabant.

3 recordsLinked to original sources
USGS1997

Mass balance, meteorological, ice motion, surface altitude, and runoff data at Gulkana Glacier, Alaska, 1993 balance year

The 1993 measured winter snow, maximum winter snow, net, and annual balances in the Gulkana Glacier basin were evaluated on the basis of meteorological, hydrological, and glaciological data measured in the basin and are reported herein. Averaged over the glacier, the measured winter snow balance was 0.81 meter on March 31, 1993, 1.2 standard deviations below the long-term average; the maximum winter snow balance, 0.84 meter, was reached on May 10, 1993 and remained until May 11, 1993; the net balance (from August 18, 1992 to September 8, 1993) was 1.80 meters, the most negative balance year on record at 2.8 standard deviations below the long-term average. The annual balance (October 1, 1992 to September 30, 1993) was 1.64 meters. Ice-surface motion and altitude changes measured at three index sites document seasonal ice speed and glacier thickness changes. Annual stream runoff was 1.996 meters averaged over the basin, 0.2 standard deviations above the long-term average.

Water-Resources Investigations Report↗
USGS1994

Assessment of the hydrologic interaction between Imikpuk Lake and the adjacent airstrip site near Barrow, Alaska, 1993

Imikpuk Lake serves as the drinking water source for the Ukpeagvik Inupiat Corporation-National Arctic Research Laboratory (UIC-NARL), formerly known as the Naval Arctic Research Laboratory, near Barrow, Alaska. During the 1970's and 1980's, accidental releases of more than 1,300 cubic meters of various types of fuel occurred at the airstrip site adjacent to the lake. To aid an assessment of the potential risk 10 the quality of water in the lake posed by fuel remaining in the subsurface, the hydrologic interaction between the lake and ground water at the airstrip site was examined. The study area lies within the region of continuous permafrost where hydrologic processes are largely controlled by the short annual thaw season and the presence of near-surface permafrost. Runoff occurs for only a short period each year, typically from early or mid-June to late September, and a shallow ground- water system develops during approximately the same period as a result of shallow thawing of the subsurface. During the spring and summer of 1993, snowpack and surface-water data were collected throughout the Imikpuk Lake basin, and subsurface- flow-system data were collected at the airstrip site. The total annual inflow to the lake was estimated 10 be approximately 300,000 cubic meters per year, based on four methods of estimation. The ground-water flow system at the airstrip site is complex, primarily because of variations in local land-surface topography. Subsurface frost-elevation data indicate that a permafrost ridge exists beneath one of the elevated building pads at the site. Similar ridges beneath elevated roadways at the site may act as impediments to ground-water flow, reducing the flux of subsurface water to Imikpuk Lake. However, on the basis of the assumption that such impediments do not reduce flux substantially, the ground-water flux from the airstrip site was estimated to be approximately 173 cubic meters per year--less than 0.1 percent of the estimated annual inflow to Imikpuk Lake.

Open-File Report↗