Accession Number : ADA183213

Title :   Use of Landsat Digital Data for Snow Cover Mapping in the Upper Saint John River Basin, Maine,

Corporate Author : COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH

Personal Author(s) : Merry,Carolyn J ; Miller,Michael S

PDF Url : ADA183213

Report Date : Jun 1987

Pagination or Media Count : 77

Abstract : Measurements of snow depth and its water equivalent were obtained at 11 snow courses in the Allagash, Maine, area in conjunction with acquisition of five Landsat-2 and -3 images during the 1977-78 and 1978-79 winters. To test a hypothesis that Landsat reflected radiance values on a regional scale do change, histograms of the Landsat MSS band 7 reflected radiance values for a 300- x 300-pixel (420 sq km) area near Allagash were evaluated to quantify the change. A statistical description (skewness and kurtosis) of the histogram for each scene was developed and and then correlated with ground measurements of snow depth. The Lansat date were then re-examined and corrections were made for solar elevation and MSS sensor calibration. Reflected radiance from open areas showed a consistent increase in intensity with increasing snow depth. Forested land cover classes did not change with snow depth. Digital imagery data acquired 31 May 1978 when the land was snow-free was used to classify land cover categories. Ground truth measurements of water equivalent of the snow cover were are-weighted using the land cover classification to derive regional values on each of the five Lansat winter scenes. The 1 March 1978 snow measurement of 19.46 cm of water equivalent was used as an input value to the SSARR model. The SSARR prediction for the 1 March-31 May 1978 period was within 78% of the measured runoff for the initial baseflow period and within 66% measured for the spring melt recession period. Keywords: Hydrologic modeling.

Descriptors :   *SNOW COVER, ACQUISITION, FORESTS, LAND AREAS, MEASUREMENT, SURFACE TRUTH, HYDROLOGY, MODELS, DATA BASES, DIGITAL SYSTEMS, IMAGE PROCESSING, GROUND LEVEL, MEASUREMENT, HISTOGRAMS, INPUT, CLASSIFICATION, MAINE, SCALE, CALIBRATION, DETECTORS, MAPPING, STATISTICS, WINTER, REFLECTION, RADIANCE, BASINS(GEOGRAPHIC), RIVERS, DEPTH, SNOW, WATER

Subject Categories : Snow, Ice and Permafrost
      Hydrology, Limnology and Potamology

Distribution Statement : APPROVED FOR PUBLIC RELEASE