| Summary: | We describe an approach to calibrating the thermal parameters of a ground undergoing cycles of freezing and thawing using exclusively time-lapse geoelectrical measurements collected from the ground surface. The method links a heat conduction model with a ground resistivity model in a fully coupled optimization approach. The data used for model calibration come from a high-latitude permafrost monitoring site in Ilulissat, West Greenland. Parameters calibrated on time-lapse geoelectrical data reproduce the calibration dataset with an accuracy comparable to that of a calibration on borehole temperature data, and reproduce the observed borehole temperatures to within ±0.6 °C. Given the underdetermined nature of the inverse problem and the simplicity of the heat model, the parameter values are non-uniquely determined in both calibration approaches. Nevertheless, the method offers the possibility of gaining an outlook of ground thermal conditions over a larger area, at lower cost and with reduced impact on the fragile arctic environment.
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