Terrestrial laser scanning (TLS) was previously used
to derive spatially continuous snow depth (Prokop, 2008;
Grünewald et al., 2010). Even though the accuracy of such
measurements is very good (usually better than 0.1 m, depending
on laser footprint and distance from sensor), largescale
catchments such as the Dischma Valley (Fig. 1) cannot
be covered completely. Data acquisition with TLS is time
and manpower consuming and only possible at easily accessible
spots under fair conditions (depending on the avalanche
situation, weather) for areas within the line of sight of the
measurement location. This results in limited coverage and
many data gaps, e.g., behind bumps. Airborne laser scanning
(ALS) from helicopters or airplanes can cover larger areas
in a shorter time also under difficult avalanche danger situations.
Recent studies demonstrate that the accurate mapping
of snow depth is possible (Deems et al., 2013; Melvold and
Skaugen, 2013). However, the costs to cover larger areas are
still high (Bühler et al., 2012) and overflights are, as with digital
photogrammetry, restricted to fair weather conditions.
Terrestrial laser scanning (TLS) was previously usedto derive spatially continuous snow depth (Prokop, 2008;Grünewald et al., 2010). Even though the accuracy of suchmeasurements is very good (usually better than 0.1 m, dependingon laser footprint and distance from sensor), largescalecatchments such as the Dischma Valley (Fig. 1) cannotbe covered completely. Data acquisition with TLS is timeand manpower consuming and only possible at easily accessiblespots under fair conditions (depending on the avalanchesituation, weather) for areas within the line of sight of themeasurement location. This results in limited coverage andmany data gaps, e.g., behind bumps. Airborne laser scanning(ALS) from helicopters or airplanes can cover larger areasin a shorter time also under difficult avalanche danger situations.Recent studies demonstrate that the accurate mappingof snow depth is possible (Deems et al., 2013; Melvold andSkaugen, 2013). However, the costs to cover larger areas arestill high (Bühler et al., 2012) and overflights are, as with digitalphotogrammetry, restricted to fair weather conditions.
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