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Zusammenfassung:
The arctic ecosystem is changing four times faster than the rest of the planet because of climate change. This increases the frequency of extreme weather events, like very strong winds, that have direct repercussions on snow properties, especially on its density. These kinds of events can prevent the foraging of the Peary caribou (Rangifer tarandus pearyi) as soon as the density of the snow exceeds 350 kg/m2, leading to nutritional deficiencies and even, in extreme cases, to mass mortality events due to famine. Unfortunately, the densification of the snow by strong winds is hard to study, as it is a very variable phenomenon at a local scale and the actual method of gathering density data is by digging up snow pits, which is time consuming and provides only punctual data. The usage of a frequency modulated continuous wave (FMCW) radar opens the possibility of developing an algorithm to retrieve snow density to characterize the spatial variability and impact of wind on the densification of snow cover. The elaboration of this algorithm is conducted using a portable FMCW radar that can be mounted on a sleigh or on a drone and used before and after strong winds, to map the characteristics of the snow cover’s stratigraphy. This method only requires the digital elevation model of the study site and basic knowledge of the ground vegetation, as it influences the radar backscatter. This study takes place in Cambridge Bay (Nunavut, Canada), in the Intensive Monitoring Area of the Canadian High-Arctic Research Station.
