Temporal Variance in Arctic Polygonal Ground Surface Water Sources

Surface water samples were collected at the Barrow Environmental Observatory (BEO, Barrow Alaska) during and after the snowmelt period in the late spring and summer of 2013. Deuterium and oxygen-18 ratios were assayed, in addition to a suite of inorganic ions. Geographic variability during the snowmelt period was evident, as well as temporal variability within a site selected for more intensive study. Distinct deuterium/hydrogen and oxygen-18/oxygen-16 ratios were observed, and were correlated to the snowmelt period, active-layer melt period, and recent precipitation events. Stable hydrogen and oxygen isotopes were used to estimate the timing and duration of the snowmelt and active layer thaws, as well as the relative contributions of snowmelt, active layer water, and recent precipitation to the surface waters. Consequently, measured concentrations of inorganic ions could be correlated to changes in the predominant source of surface water at a given time. These data and correlations will inform the development of improved hydrological and biogeochemical models of Arctic polygonal ground.