Detection of Seasonal Arctic Terrain Change Using a Small Unmanned Aircraft System (sUAS) on the Alaskan North Slope

Numerous locations across the Arctic have exhibited signs of landscape change due to permafrost thaw. However, due to the remoteness of much of the Arctic, ground-based measurements are difficult to make. Remotely sensed platforms provide promise for characterizing broad areas of the landscape. We analyzed landscape change associated with permafrost thaw (i.e., thermokarst development) near seasonal rivers and streams flowing from the Brooks Range to the Beaufort Sea on the North Slope of Alaska. This multidisciplinary project is investigating variability in arctic river chemistry, material fluxes, and thermokarst terrain change during summer season thaw. Photogrammetric topographic surveys were conducted at four selected study sites using a fixed-wing small unmanned aircraft system (sUAS). Ground control points (GCPs) were emplaced throughout the study areas and coordinates were established with post-processed Global Navigation Satellite System (GNSS) occupations. Digital imagery was acquired at an altitude of approximately 75 m above ground level (AGL) resulting in ground sample distances (GSDs) of around 1.3 cm. This paper presents terrain change results spanning a three-month period (June-September 2019) for one of the study sites and discusses some of the challenges of performing sUAS-based change detection in a remote arctic tundra environment.