Using Ground Penetrating Radar to Estimate Talik Thickness Below the Kuparuk River, Arctic Alaska

Continued climate warming directly impacts regional hydrological systems through increased permafrost degradation and talik expansion. These disturbances alter surface and groundwater flow paths, increasing uncertainty in hydrological responses to future climate change. Previous research has observed groundwater flow in permafrost regions, either through suprapermafrost taliks or subpermafrost aquifers; however, a near-surface geophysical approach to quantify talik volume is required. We used Ground Penetrating Radar (GPR) data collected in March 2025 to estimate talik thickness below the Kuparuk River on the North Slope of Alaska. The Kuparuk River extends from the Brooks Range to the Beaufort Sea, making this region imperative for understanding the impacts of permafrost degradation on hydrological systems within the Arctic tundra.  GPR measurements were collected using a snowmobile pulling a 160 MHz antenna, reaching a depth of investigation up to ~30m. Preliminary GPR results suggest a talik layer below the river, which is hypothesized to facilitate groundwater flow during the winter. GPR talik thicknesses will be used to create a conceptual hydrogeological model of this complex river-talik system. This work provides a better understanding of the impacts of permafrost degradation on groundwater flow in an increasing climate warming.