Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Sub-aerial talik formation observed across the discontinuous permafrost zone of Alaska


Talik formation has long been acknowledged as an important mechanism of permafrost degradation. Currently, a lack of in situ observations has left a critical gap in our understanding of how ongoing climate change may influence future sub-aerial talik formation in areas unaffected by water bodies or wildfire. Here we present in situ ground temperature measurements from undisturbed sub-aerial sites across the discontinuous permafrost zone of Alaska between 1999 and 2020. We find that novel taliks formed at 24 sites across the region, with widespread initiation occurring during the winter of 2018 due to higher air temperatures and above-average snowfall insulating the soil. Future projections under a high emissions scenario show that by 2030, talik formation will initiate across up to 70% of the discontinuous permafrost zone, regardless of snow conditions. By 2090, talik in areas of black spruce forest, and warmer ecosystems, may reach a thickness of 12 m. The establishment of widespread sub-aerial taliks has major implications for permafrost thaw, thermokarst development, carbon cycling, hydrological connectivity and engineering.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Prices vary by article type



Prices may be subject to local taxes which are calculated during checkout

Fig. 1: An overview of monitoring locations and timing of talik development.
Fig. 2: FDD, TDD and snow-depth values at key sites.
Fig. 3: Example of talik formation at six sites from across the study region.
Fig. 4: PT, PF and talik thickness through time.

Data availability

Ground temperature can be obtained from, through the data repositories cited within Supplementary Table 1 or from the authors upon request. Source data are provided with this paper.

Code availability

The GIPL model used to estimate potential thaw, potential freeze and talik thickness is freely available via GitHub at


  1. Romanovsky, V. et al. in Snow, Water, Ice and Permafrost in the Arctic (SWIPA) 2017 65–102 (Arctic Monitoring and Assessment Programme, 2017).

  2. Biskaborn, B. K. et al. Permafrost is warming at a global scale. Nat. Commun. (2019).

  3. Farquharson, L. M. et al. Climate change drives widespread and rapid thermokarst development in very cold permafrost in the Canadian High Arctic. Geophys. Res. Lett. (2019).

  4. Ward Jones, M. K., Pollard, W. H. & Jones, B. M. Rapid initialization of retrogressive thaw slumps in the Canadian High Arctic and their response to climate and terrain factors. Environ. Res. Lett. (2019).

  5. Lewkowicz, A. G. & Way, R. G. Extremes of summer climate trigger thousands of thermokarst landslides in a High Arctic environment. Nat. Commun. 10, 1329 (2019).

    Article  Google Scholar 

  6. Fraser, R. H. et al. Climate sensitivity of High Arctic permafrost terrain demonstrated by widespread ice-wedge thermokarst on Banks Island. Remote Sens. 10, 954 (2018).

  7. Walter Anthony, K. et al. 21st-century modeled permafrost carbon emissions accelerated by abrupt thaw beneath lakes. Nat. Commun. (2018).

  8. Jafarov, E. E. et al. Modeling the role of preferential snow accumulation in through talik development and hillslope groundwater flow in a transitional permafrost landscape. Environ. Res. Lett. (2018).

  9. Haynes, K. M., Connon, R. F. & Quinton, W. L. Permafrost thaw induced drying of wetlands at Scotty Creek, NWT, Canada. Environ. Res. Lett. (2018).

  10. Devoie, É. G., Craig, J. R., Connon, R. F. & Quinton, W. L. Taliks: a tipping point in discontinuous permafrost degradation in peatlands. Water Resour. Res. (2019).

  11. Kessler, M. A., Plug, L. J. & Walter Anthony, K. M. Simulating the decadal- to millennial-scale dynamics of morphology and sequestered carbon mobilization of two thermokarst lakes in NW Alaska. J. Geophys. Res. Biogeosci. (2012).

  12. Stephani, E., Drage, J., Miller, D., Jones, B. M. & Kanevskiy, M. Taliks, cryopegs, and permafrost dynamics related to channel migration, Colville River Delta, Alaska. Permafr. Periglac. Process. (2020).

  13. Gibson, C. M. et al. Wildfire as a major driver of recent permafrost thaw in boreal peatlands. Nat. Commun. (2018).

  14. Rey, D. M. et al. Wildfire‐initiated talik development exceeds current thaw projections: observations and models from Alaska’s continuous permafrost zone. Geophys. Res. Lett. 47, e2020GL087565 (2020).

  15. Walvoord, M. A., Voss, C. I., Ebel, B. A. & Minsley, B. J. Development of perennial thaw zones in boreal hillslopes enhances potential mobilization of permafrost carbon. Environ. Res. Lett. (2019).

  16. Connon, R., Devoie, É., Hayashi, M., Veness, T. & Quinton, W. The influence of shallow taliks on permafrost thaw and active layer dynamics in subarctic Canada. J. Geophys. Res. Earth Surf. (2018).

  17. Lader, R., Walsh, J. E., Bhatt, U. S. & Bieniek, P. A. Projections of twenty-first-century climate extremes for Alaska via dynamical downscaling and quantile mapping. J. Appl. Meteorol. Climatol. (2017).

  18. Parazoo, N. C., Koven, C. D., Lawrence, D. M., Romanovsky, V. & Miller, C. E. Detecting the permafrost carbon feedback: talik formation and increased cold-season respiration as precursors to sink-to-source transitions. Cryosphere (2018).

  19. Nicolsky, D. J., Romanovsky, V. E., Panda, S. K., Marchenko, S. S. & Muskett, R. R. Applicability of the ecosystem type approach to model permafrost dynamics across the Alaska North Slope. J. Geophys. Res. Earth Surf. (2017).

  20. Turetsky, M. R. et al. Carbon release through abrupt permafrost thaw. Nat. Geosci. (2020).

  21. Nitze, I., Grosse, G., Jones, B. M., Romanovsky, V. E. & Boike, J. Remote sensing quantifies widespread abundance of permafrost region disturbances across the Arctic and subarctic. Nat. Commun. 9, 5423 (2018).

  22. Olefeldt, D. et al. Circumpolar distribution and carbon storage of thermokarst landscapes. Nat. Commun. 7, 13043 (2016).

  23. Ferrians, O. J., Kachadoorian, R. & Greene, G. W. Permafrost and Related Engineering Problems in Alaska (US Government Printing Office, 1969).

  24. O’Neill, H. B., Roy‐Leveillee, P., Lebedeva, L. & Ling, F. Recent advances (2010–2019) in the study of taliks. Permafr. Periglac. Process. (2020).

  25. French, H. The Periglacial Environment (Wiley, 1996).

  26. Williams, P. J. & Smith, M. W. The Frozen Earth: Fundamentals of Geocryology (Cambridge Univ. Press, 1989);

  27. Walsh, J. E. & Brettschneider, B. Attribution of recent warming in Alaska. Polar Sci. (2019).

  28. Sturm, M. et al. Snow–shrub interactions in Arctic tundra: a hypothesis with climatic implications. J. Clim. 14, 336–344 (2001).

  29. Romanovsky, V. E. & Osterkamp, T. E. Interannual variations of the thermal regime of the active layer and near‐surface permafrost in northern Alaska. Permafr. Periglac. Process. (1995).

  30. Sturm, M., Perovich, D. K. & Holmgren, J. Thermal conductivity and heat transfer through the snow on the ice of the Beaufort Sea. J. Geophys. Res. Oceans (2002).

  31. Goodrich, L. E. The influence of snow cover on the ground thermal regime. Can. Geotech. J. 19, 421–432 (1982).

    Article  Google Scholar 

  32. Romanovsky, V. E. & Osterkamp, T. E. Effects of unfrozen water on heat and mass transport processes in the active layer and permafrost. Permafr. Periglac. Process. 11, 219–239 (2000).

  33. Jorgenson, M. T. et al. Resilience and vulnerability of permafrost to climate change. Can. J. For. Res. (2010).

  34. Douglas, T. A. et al. Recent degradation of Interior Alaska permafrost mapped with ground surveys, geophysics, deep drilling, and repeat airborne LiDAR. Cryosphere 15, 3555–3575 (2021).

    Article  Google Scholar 

  35. Dyrness, C. T. Control of Depth to Permafrost and Soil Temperature by the Forest Floor in Black Spruce/Feathermoss Communities Research Note PNW-RN-396 (USDA, 1982).

  36. Jafarov, E. E., Romanovsky, V. E., Genet, H., McGuire, A. D. & Marchenko, S. S. The effects of fire on the thermal stability of permafrost in lowland and upland black spruce forests of Interior Alaska in a changing climate. Environ. Res. Lett. (2013).

  37. Farouki, O. T. The thermal properties of soils in cold regions. Cold Reg. Sci. Technol. 5, 67–75 (1981).

    Article  Google Scholar 

  38. Homer, C. G. et al. Completion of the 2011 National Land Cover Database for the conterminous United States—representing a decade of land cover change information. Photogramm. Eng. Remote Sens. 81, 345–354 (2015).

    Google Scholar 

  39. Brown, J., Ferrians Jr, O. J., Heginbottom, J. A. & Melnikov, E. S. Circum-Arctic Map of Permafrost and Ground-Ice Conditions. (USGS, 1997).

  40. Osterkamp, T. E. et al. Observations of thermokarst and its impact on boreal forests in Alaska, USA. Arct. Antarct. Alp. Res. 32, 303–315 (2000).

  41. Collins, M. et al. in Climate Change 2013: The Physical Science Basis (eds Stocker, T. F. et al.) 1029–1136 (Cambridge Univ. Press, 2013).

  42. Connon, R. F., Quinton, W. L., Craig, J. R. & Hayashi, M. Changing hydrologic connectivity due to permafrost thaw in the lower Liard River valley, NWT, Canada. Hydrol. Process. 28, 4163–4178 (2014).

    Article  Google Scholar 

  43. Rowland, J. C., Travis, B. J. & Wilson, C. J. The role of advective heat transport in talik development beneath lakes and ponds in discontinuous permafrost. Geophys. Res. Lett. (2011).

  44. James, S. R. et al. The biophysical role of water and ice within permafrost nearing collapse: insights from novel geophysical observations. J. Geophys. Res. Earth Surf. (2021).

  45. Kanevskiy, M. et al. Patterns and rates of riverbank erosion involving ice-rich permafrost (yedoma) in northern Alaska. Geomorphology (2016).

  46. Jorgenson, M. T. et al. Permafrost characteristics of Alaska—a new permafrost map of Alaska. In Proc. Ninth International Conference on Permafrost (eds Kane, D. L. & Hinkel, K. M.) 121–122 (Institute of Northern Engineering, Univ. Alaska Fairbanks, 2008).

  47. Shur, Y. L. & Jorgenson, M. T. Patterns of permafrost formation and degradation in relation to climate and ecosystems. Permafr. Periglac. Process. 18, 7–19 (2007).

    Article  Google Scholar 

  48. French, H. M. Past and present permafrost as an indicator of climate change. Polar Res. 18, 269–274 (1999).

    Article  Google Scholar 

  49. Hamilton, T., Craig, J. & Sellman, P. The Fox permafrost tunnel: a late Quaternary geologic record in central Alaska. GSA Bull. 100, 948–969 (1988).

    Article  Google Scholar 

  50. Romanovsky, V., Cable, W. & Dolgikh, K. Soil Temperature and Moisture, Kougarok Road Mile Marker 64, Seward Peninsula, Alaska, Beginning 2016 (Oak Ridge National Laboratory, 2020);

  51. Romanovsky, V., Cable, W. & Dolgikh, K. Soil Temperature and Moisture, Teller Road Mile Marker 27, Seward Peninsula, Alaska, Beginning 2016 (Oak Ridge National Laboratory, 2020);

  52. Osterkamp, T. E. & Romanovsky, V. E. Freezing of the active layer on the coastal plain of the Alaskan Arctic. Permafr. Periglaci. Process. 8, 23–44 (1997).

  53. Pardo Lara, R., Berg, A. A., Warland, J. & Tetlock, E. In situ estimates of freezing/melting point depression in agricultural soils using permittivity and temperature measurements. Water Resour. Res. (2020).

  54. Kudryavtsev, V. A., Garagulya, L. S. & Melamed, V. G. Fundamentals of Frost Forecasting in Geological Engineering Investigations (US Army Cold Regions Research and Engineering Laboratory, 1977).

  55. Nicolsky, D. J., Romanovsky, V. E., Alexeev, V. A. & Lawrence, D. M. Improved modeling of permafrost dynamics in a GCM land-surface scheme. Geophys. Res. Lett. (2007).

  56. Marchenko, S., Romanovsky, V. & Tipenko, G. Numerical modeling of spatial permafrost dynamics in Alaska. In Proc. Ninth International Conference on Permafrost (eds Kane, D. L. & Hinkel, K. M.) 1125–1130 (Institute of Northern Engineering, 2008).

  57. Alexiades, V., Solomon, A. D. & Lunardini, V. J. Mathematical modeling of melting and freezing processes. J. Sol. Energy Eng. (1993).

  58. Pollack, H. N., Hurter, S. J. & Johnson, J. R. Heat flow from the Earth’s interior: analysis of the global data set. Rev. Geophys. (1993).

  59. Marchuk, G. I. & Brown, A. A. Methods of Numerical Mathematics, vol. 2, 2nd edn. (Springer, 1982).

Download references


This work was funded by NSF AON Award numbers 1832238 (L.M.F., V.E.R., D.N. and A.K.) and 1304271 (L.M.F., V.E.R., D.N. and A.K.), NSF-funded Bonanza Creek LTER project (V.E.R.), the Department of Energy Next Generation Ecosystem Experiment Arctic (NGEE-Arctic) (L.M.F., V.E.R. and A.K.) and the Tomsk State University Development Programme (Priority-2030) (D.N.). We thank B. Cable, K. Dolgikh and C. Wright for maintaining permafrost monitoring stations and B. Gaglioti for assistance calculating thawing degree day and freezing degree day values.

Author information

Authors and Affiliations



V.E.R. and L.M.F. conceived the study and conducted data collection and analysis. L.M.F. led manuscript writing. V.E.R. conducted numerical modelling. D.N. conducted model validation and data analysis. A.K. contributed to ground temperature monitoring and data collection.

Corresponding author

Correspondence to Louise M. Farquharson.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Geoscience thanks Boris Biskaborn, Élise Devoie and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Tom Richardson, in collaboration with the Nature Geoscience team.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Extended Data Fig. 1 GIPL model validation for Smith Lake #2 site.

Model output is plotted against observations from ground temperature sensors in permafrost boreholes. RMSE error, 0.84 °C.

Extended Data Fig. 2 GIPL model validation for the Bonanza Creek site.

Model output is plotted against observations from ground temperature sensors in permafrost boreholes. RMSE error, 1.2 °C.

Extended Data Fig. 3 Bonanza Creek volumetric liquid water content (%) and ground temperature (°C) at 0.54 m depth between fall 2009 and summer 2019.

Note the lack of freezing during the winters of 2017–2018 and 2018–2019.

Extended Data Fig. 4 A comparison of measured active layer depths and those modeled by the GIPL model for Bonanza Creek.

Active layer depths were measured using an active layer probe at the end of the summer (late August) over an 18-year period. The labels indicate the year of measurement.

Supplementary information

Supplementary Information

Supplementary Tables 2–4 and Figs. 1–31.

Supplementary Table 1

A summary of talik formation at all sites, along with metadata and data sources

Source data

Source Data Fig. 2

Raw data for thawing degree days, freezing degree days and snowfall.

Source Data Fig. 4

Raw data from potential thaw, potential freeze, active-layer depths and talik thickness for Bonanza Creek and SL#2 sites; data include model input files for model runs and the GIPL model.exe file.

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Farquharson, L.M., Romanovsky, V.E., Kholodov, A. et al. Sub-aerial talik formation observed across the discontinuous permafrost zone of Alaska. Nat. Geosci. 15, 475–481 (2022).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing