Water tracks in the High Arctic: a hydrological network dominated by rapid subsurface flow through patterned ground

Abstract

Water tracks play a major role in the headwater basin hydrology of permafrost landscapes in Alaska and Antarctica, but less is known about these features in the High Arctic. We examined the physical and hydrological properties of water tracks on Ward Hunt Island, a polar desert site in the Canadian High Arctic, to evaluate their formation process and to compare with water tracks reported elsewhere. These High Arctic water tracks flowed through soils that possessed higher near-surface organic carbon concentrations, higher water content, and coarser material than the surrounding soils. The water track morphology suggested they were initiated by a combination of sorting, differential frost heaving, and eluviation. The resultant network of soil conduits, comparable to soil pipes, dominated the hydrology of the slope. The flow of cold water through these conduits slowed down the progression of the thawing front during summer, making the active layer consistently shallower relative to adjacent soils. Water tracks on Ward Hunt Island, and in polar desert catchments with these features elsewhere in the High Arctic, strongly influence slope hydrology and active-layer properties while also affecting vegetation distribution and the quality of runoff to the downstream lake.