Aerial measurements of snow water equivalent in Norway using terrestrial gamma radiation

Airborne measurement of gamma radiation is used to determine the water equivalent of the snow magazines in 8000 km2 of mountainous areas in Southern Norway. The terrain in the areas is exposed to strong winds, causing considerable variation in the snow cover. This is regarded as a source of error. A method to reduce this error is described in this report. As the terrain is inhomogeneous in most of the measurement areas careful selection of survey lines is important. The cost of surveying 1000 km of measurement routes was N.kr. 40000 or US$ 8000 in 1978. (Auth.)