Potential for inferring freshwater lake ice thickness by GPS interferometric reflectometry

Recently, it has been reported that the refracted, reflected and scattered signals of global navigation satellite systems (GNSS) have been successfully used to remotely sense the Earth´s surface and atmosphere. For example, it has been reported that reflected global positioning system (GPS) signals can provide useful information about the land-surface composition such as snow depth. From recent snow depth studies, this promising new technique has been given the name GPS interferometric reflectometry (GPS-IR). This method is basically an L-band ground-based interferometer. Its basic mechanism is the interference between the direct (line-of-sight) signal and the multipath signals, reflected from near-ground surfaces such as snow, ice, water, etc. Here, we explore the possibility of estimating freshwater lake ice thickness. In particular, a GPS receiver is located above a frozen lake. With this setup, the received power variations with respect to the changing satellite elevation angle are calculated and measured. A case study shows potential for inferring lake ice thickness by fitting the theory to the measurements using a nonlinear least squares fitting algorithm.