Water isotopes to quantify lake water balances in the Peace-Athabasca Delta

Related Journal Publication: Remmer, CR, Owca, T, Neary, L, et al. Delineating extent and magnitude of river flooding to lakes across a northern delta using water isotope tracers. Hydrological Processes. 2020; 34: 303– 320. https://doi.org/10.1002/hyp.13585

Surface water samples were collected from 57-60 lakes and 9 river sites spanning the two main sectors of the PAD three times during the ice-free seasons of five consecutive years, 2015-2019. To capture and compare the effects of hydrological processes (i.e., snowmelt, spring ice-jam flooding, open-water flooding, evaporation and rainfall), samples were consistently collected during two to three-week intervals in the spring (May), summer (July) and fall (September) of each year. An exception occurred in 2016 when the Fort McMurray (Alberta) regional wildfire delayed our spring sample collection by three weeks (June). Samples were collected mid-lake (or mid-channel) from a depth of ~10 cm and stored in sealed 30 ml high-density polyethylene bottles. Lake water isotope compositions were measured by Off-Axis Integrated Cavity Output Spectroscopy (O-AICOS) at the University of Waterloo – Environmental Isotope Laboratory (UW-EIL). Isotope compositions are expressed as δ-values, representing deviations in per mil (‰) from Vienna Standard Mean Ocean Water (VSMOW) such that δ-sample = [(Rsample/RVSMOW) - 1] x 103, where R is the 18O/16O or 2H/1H ratio in the sample and VSMOW. Results of δ18O and δ2H analyses are normalized to -55.5‰ and -428‰, respectively, for Standard Light Antarctic Precipitation (Coplen, 1996). Analytical uncertainties are ±0.2‰ for δ18O and ±0.8‰ for δ2H.

The data was collected to quantify lake water balances in the Peace-Athabasca Delta using water isotopes.

Peace-Athabasca Delta