IAHS2022-328, updated on 01 Dec 2022
https://doi.org/10.5194/iahs2022-328
IAHS-AISH Scientific Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Groundwater-surface water interactions and associated greenhouse gas evasion in the High Arctic

Andrea L. Popp1, Nicolas Valiente2,3, Sigrid Trier Kjær1,4, Anja Sundal1,5, Kristoffer Aalstad1, Alexander Eiler2, and Peter Dörsch4
Andrea L. Popp et al.
  • 1Department of Geosciences, University of Oslo, Oslo, Norway
  • 2Department of Biosciences, University of Oslo, Oslo, Norway
  • 3Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
  • 4Faculty of Environmental Sciences and Natural Resource Management, NMBU, Ås, Norway
  • 5Norwegian Space Agency, Oslo, Norway

Global warming in the Arctic is occurring at an amplified rate, resulting in enhanced permafrost thaw (e.g., Meredith et al., 2019). As permafrost thaws, layers of year-round unfrozen ground, so-called taliks, are created (Figure 1). Taliks represent new subsurface pathways that involve unknown consequences for fluxes of water, energy and solutes (e.g., Walvoord & Kurylyk, 2016).  With this study, we aim to contribute to an improved understanding of the current status of Arctic hydrology and biogeochemistry using a combination of modelling as well as satellite- and field-derived data from the Bayelva catchment in Ny-Ålesund, Svalbard. In summer 2021, we sampled various water sources (e.g., streams, lakes, snow, glacial meltwater, groundwater) to obtain a spatially resolved data set of tracers (e.g., major ions, radon, stable water isotopes, trace elements) and greenhouse gases (GHGs; CO2, CH4, N2O). Consequently, we delineate source water contributions to streams and lakes using conservative tracers combined with a mixing model (Popp et al., 2019). With the help of radon, we assess hyporheic exchange flow and short residence times (Popp et al., 2021). Lastly, to identify drivers and controls of GHG evasion, we link source water contributions and GHG concentrations. This work captures the current state of an Arctic catchment experiencing rapid changes and can therefore help to predict future effects of permafrost thaw and its impact on water cycle changes and GHG evasion.

References:

Meredith, M. et al. (2019). Polar regions. IPCC Special Report on the Ocean and Cryosphere in a Changing Climate [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegrı́a, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)].

Popp, A. L. et al. (2019). Integrating Bayesian groundwater mixing modeling with on-site helium analysis to identify unknown water sources. Water Resources Research, 55(12), 10602– 10615. https://doi.org/10.1029/2019WR025677

Popp, A. L. et al. (2021). A framework for untangling transient groundwater mixing and travel times. Water Resources Research, 57. https://doi.org/10.1029/2020WR028362

Walvoord, M. A., & Kurylyk, B. L. (2016). Hydrologic Impacts of Thawing Permafrost-A Review. Vadose Zone Journal, 15 (6), vzj2016.01.0010. doi:10.2136/vzj2016.01.0010

How to cite: Popp, A. L., Valiente, N., Trier Kjær, S., Sundal, A., Aalstad, K., Eiler, A., and Dörsch, P.: Groundwater-surface water interactions and associated greenhouse gas evasion in the High Arctic, IAHS-AISH Scientific Assembly 2022, Montpellier, France, 29 May–3 Jun 2022, IAHS2022-328, https://doi.org/10.5194/iahs2022-328, 2022.