Low-altitude aerial thermography for the archaeological investigation of arctic landscapes

Remotely-piloted aircraft (RPA) thermography is one of the least utilized remote-sensing methods in archaeology, yet it has great potential for visualizing subsurface archaeological features. Given the logistic constraints of remote fieldwork, arctic archaeologists have much to gain from this portable and effective remote-sensing application. This paper presents a novel methodological approach for the collection, processing, and analysis of RPA thermal imagery in the Canadian High Arctic that accounts for the unique environmental and logistic challenges of RPA applications in polar regions. The development of this approach is based on a case study of two Pre-Inuit (4500-1000 B.P.) archaeological sites from the Foxe Basin region, Nunavut. The presented workflow demonstrates the effectiveness of RPA thermography in archaeological feature detection in an Arctic-tundra setting. Thermal detection of several previously unidentified subsurface features in Foxe Basin suggest that surface feature visibility is lower than previously anticipated, calling attention to potential judgemental biases in pedestrian archaeological surveys in Arctic contexts. Based on the utility of low-altitude thermography for visualizing the internal structures of Tuniit dwellings, this paper proposes that thermography facilitates archaeological spatial analysis beyond feature prospection. RPA thermography is a non-destructive and economic remote-sensing solution to some of the persistent logistic challenges to fieldwork in remote locations that often inhibit large-scale archaeological analyses not only in the Canadian Arctic, but remote Arctic-Alpine regions worldwide.