Journal metrics

Journal metrics

  • IF value: 4.524 IF 4.524
  • IF 5-year value: 5.558 IF 5-year 5.558
  • CiteScore value: 4.84 CiteScore 4.84
  • SNIP value: 1.425 SNIP 1.425
  • SJR value: 3.034 SJR 3.034
  • IPP value: 4.65 IPP 4.65
  • h5-index value: 52 h5-index 52
  • Scimago H index value: 55 Scimago H index 55
The Cryosphere, 11, 2975-2996, 2017
https://doi.org/10.5194/tc-11-2975-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
15 Dec 2017
Shifted energy fluxes, increased Bowen ratios, and reduced thaw depths linked with drainage-induced changes in permafrost ecosystem structure
Mathias Göckede1, Fanny Kittler1, Min Jung Kwon1,a, Ina Burjack1, Martin Heimann1,2, Olaf Kolle1, Nikita Zimov3, and Sergey Zimov3 1Max Planck Institute for Biogeochemistry, Jena, Germany
2Division of Atmospheric Sciences, Department of Physics, University of Helsinki, Helsinki, Finland
3North-East Science Station, Pacific Institute for Geography, Far-Eastern Branch of Russian Academy of Science, Chersky, Republic of Sakha (Yakutia), Russia
anow at: Division of Polar Life Sciences, Korea Polar Research Institute, Incheon, Republic of Korea
Abstract. Hydrologic conditions are a key factor in Arctic ecosystems, with strong influences on ecosystem structure and related effects on biogeophysical and biogeochemical processes. With systematic changes in water availability expected for large parts of the northern high-latitude region in the coming centuries, knowledge on shifts in ecosystem functionality triggered by altered water levels is crucial for reducing uncertainties in climate change predictions. Here, we present findings from paired ecosystem observations in northeast Siberia comprising a drained and a control site. At the drainage site, the water table has been artificially lowered by up to 30 cm in summer for more than a decade. This sustained primary disturbance in hydrologic conditions has triggered a suite of secondary shifts in ecosystem properties, including vegetation community structure, snow cover dynamics, and radiation budget, all of which influence the net effects of drainage. Reduced thermal conductivity in dry organic soils was identified as the dominating drainage effect on energy budget and soil thermal regime. Through this effect, reduced heat transfer into deeper soil layers leads to shallower thaw depths, initially leading to a stabilization of organic permafrost soils, while the long-term effects on permafrost temperature trends still need to be assessed. At the same time, more energy is transferred back into the atmosphere as sensible heat in the drained area, which may trigger a warming of the lower atmospheric surface layer.

Citation: Göckede, M., Kittler, F., Kwon, M. J., Burjack, I., Heimann, M., Kolle, O., Zimov, N., and Zimov, S.: Shifted energy fluxes, increased Bowen ratios, and reduced thaw depths linked with drainage-induced changes in permafrost ecosystem structure, The Cryosphere, 11, 2975-2996, https://doi.org/10.5194/tc-11-2975-2017, 2017.
Publications Copernicus
Download
Short summary
Shifts in hydrologic conditions will be a key factor for the sustainability of Arctic ecosystems under future climate change. Using a long-term manipulation experiment, we analyzed how energy exchange processes within a permafrost ecosystem react to sustained dry conditions. Changes in several important ecosystem characteristics lead to reduced evapotranspiration and increased sensible heat fluxes. Heat transfer into the soil was strongly reduced, keeping the permafrost colder.
Shifts in hydrologic conditions will be a key factor for the sustainability of Arctic ecosystems...
Share