Articles | Volume 15, issue 17
Biogeosciences, 15, 5287–5313, 2018
Biogeosciences, 15, 5287–5313, 2018

Reviews and syntheses 31 Aug 2018

Reviews and syntheses | 31 Aug 2018

Reviews and syntheses: Changing ecosystem influences on soil thermal regimes in northern high-latitude permafrost regions

Michael M. Loranty1, Benjamin W. Abbott2, Daan Blok3, Thomas A. Douglas4, Howard E. Epstein5, Bruce C. Forbes6, Benjamin M. Jones7, Alexander L. Kholodov8, Heather Kropp1, Avni Malhotra9, Steven D. Mamet10, Isla H. Myers-Smith11, Susan M. Natali12, Jonathan A. O'Donnell13, Gareth K. Phoenix14, Adrian V. Rocha15, Oliver Sonnentag16, Ken D. Tape7, and Donald A. Walker17 Michael M. Loranty et al.
  • 1Department of Geography, Colgate University, Hamilton, NY 13346, USA
  • 2Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT 84602, USA
  • 3Department of Physical Geography and Ecosystem Science, Lund University, 223 62 Lund, Sweden
  • 4U.S. Army Cold Regions Research and Engineering Laboratory Fort Wainwright, Alaska 99703, USA
  • 5Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
  • 6Arctic Centre, University of Lapland, 96101, Rovaniemi, Finland
  • 7Institute of Northern Engineering, Water & Environmental Research Center, University of Alaska, Fairbanks, AK 99775, USA
  • 8Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, 99775 USA
  • 9Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, 37831-6301, USA
  • 10Department of Soil Science, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
  • 11School of GeoSciences, University of Edinburgh, Edinburgh, UK
  • 12Woods Hole Research Center, Falmouth, MA 02540, USA
  • 13Arctic Network, National Park Service, Anchorage, AK 99501, USA
  • 14Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
  • 15Department of Biological Sciences and the Environmental Change Initiative, University of Notre Dame, Notre Dame 46556, USA
  • 16Département de géographie, Université de Montréal, Montréal, H2V 2B8, Canada
  • 17Institute of Arctic Biology, University of Alaska Fairbanks, AK 99775, USA

Abstract. Soils in Arctic and boreal ecosystems store twice as much carbon as the atmosphere, a portion of which may be released as high-latitude soils warm. Some of the uncertainty in the timing and magnitude of the permafrost–climate feedback stems from complex interactions between ecosystem properties and soil thermal dynamics. Terrestrial ecosystems fundamentally regulate the response of permafrost to climate change by influencing surface energy partitioning and the thermal properties of soil itself. Here we review how Arctic and boreal ecosystem processes influence thermal dynamics in permafrost soil and how these linkages may evolve in response to climate change. While many of the ecosystem characteristics and processes affecting soil thermal dynamics have been examined individually (e.g., vegetation, soil moisture, and soil structure), interactions among these processes are less understood. Changes in ecosystem type and vegetation characteristics will alter spatial patterns of interactions between climate and permafrost. In addition to shrub expansion, other vegetation responses to changes in climate and rapidly changing disturbance regimes will affect ecosystem surface energy partitioning in ways that are important for permafrost. Lastly, changes in vegetation and ecosystem distribution will lead to regional and global biophysical and biogeochemical climate feedbacks that may compound or offset local impacts on permafrost soils. Consequently, accurate prediction of the permafrost carbon climate feedback will require detailed understanding of changes in terrestrial ecosystem distribution and function, which depend on the net effects of multiple feedback processes operating across scales in space and time.

Short summary
Vegetation and soils strongly influence ground temperature in permafrost ecosystems across the Arctic and sub-Arctic. These effects will cause differences rates of permafrost thaw related to the distribution of tundra and boreal forests. As the distribution of forests and tundra change, the effects of climate change on permafrost will also change. We review the ecosystem processes that will influence permafrost thaw and outline how they will feed back to climate warming.
Final-revised paper