Steven R. Fassnacht

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[1] Inverse weighted distance and regression nonexact techniques were evaluated for interpolating methods snow water equivalent (SWE) across the entire Colorado River Basin of the western United States. A 1-km spacing was used for the gridding of snow telemetry (SNOTEL) measurements for the years 1993, 1998, and 1999, which on average, represented higher(More)
The temporal and spatial continuity of spatially distributed estimates of snow-covered area (SCA) are limited by the availability of cloud-free satellite imagery; this also affects spatial estimates of snow water equivalent (SWE), as SCA can be used to define the extent of snow telemetry (SNOTEL) point SWE interpolation. In order to extend the continuity of(More)
During the 2006–2007 winter season, 17 sites across the US including Alaska tested an automated snow measurement system. This article aims to describe successes and failures of this system and provide insight into data collected this season. The system was designed in collaboration with both Environment Canada and Snow Sensor Study participants during the(More)
Previous research using meteorological station data suggests that temperatures and precipitation have been changing more across the semi-arid and arid country of Mongolia than in many other locations across the globe. We used gridded monthly data to determine the annual and seasonal rate of change in total precipitation (P), maximum temperature (Tmax), and(More)
The snow surface is very dynamic, and the roughness of the snowpack surface varies spatially and temporally. The snow surface roughness influences the movement of air across the snow surface as well as the resulting transfers of energy, and is used to estimate the sensible and latent heat fluxes to and/or from the snow surface to the atmosphere. In the(More)
The energy and water balances at the earth’s surface are dramatically influenced by the presence of snow cover. Therefore, soil temperature and moisture for snow-covered and snow-free areas can be very different. In computing these soil state variables, many land surface schemes in climate models do not explicitly distinguish between snow-covered and(More)
Mongolia has one of the strongest climate warming signals on Earth, and over 40% of the human population depends directly or indirectly on pastoral livestock production for their livelihoods. Thus, climate-driven changes in rangeland production will likely have a major effect on pastoral livelihoods. We examined patterns of climate change and rangeland(More)
The snow surface is the interface between the atmosphere and the earth. It is very dynamic, and varies spatially and temporally. Its roughness influences turbulence and is used to estimate the sensible and latent heat fluxes to and/or from the snow surface to the atmosphere. We use airborne lidar-derived snow surface measurements from the NASA Cold Land(More)
Snowpack properties vary spatially and temporally. Three snow depth datasets are evaluated to assess this variability across different scales: operational station data, auxiliary field measurements and remotely sensed estimates from the Geoscience Laser Altimeter System (GLAS) lidar instrument that was aboard the Ice, Cloud and land Elevation Satellite(More)