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Complexity revealed in the greening of the Arctic

Nature Climate Change volume 10, pages 106–117 (2020)Cite this article

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Abstract

As the Arctic warms, vegetation is responding, and satellite measures indicate widespread greening at high latitudes. This ‘greening of the Arctic’ is among the world’s most important large-scale ecological responses to global climate change. However, a consensus is emerging that the underlying causes and future dynamics of so-called Arctic greening and browning trends are more complex, variable and inherently scale-dependent than previously thought. Here we summarize the complexities of observing and interpreting high-latitude greening to identify priorities for future research. Incorporating satellite and proximal remote sensing with in-situ data, while accounting for uncertainties and scale issues, will advance the study of past, present and future Arctic vegetation change.

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Fig. 1: Satellite records indicate greening trends across the circumpolar Arctic.
Fig. 2: Ecological interpretation of trends in NDVI requires a consideration of non-ecological factors.
Fig. 3: Spatial heterogeneity in landcover can influence NDVI–vegetation relationships.
Fig. 4: Satellite-derived estimates do not always match in-situ observations of plant phenology across the growing season.
Fig. 5: Arctic greening is influenced by issues of measurement scale and inference across ecological hierarchies.

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Data availability

Data come from publicly available remote sensing and ecological datasets including: MODIS (https://modis.gsfc.nasa.gov/), GIMMS3g.v1 (https://nex.nasa.gov/nex/projects/1349/), the High Latitude Drone Ecology Network (https://arcticdrones.org/), shrub abundance, annual growth ring and phenology datasets (https://github.com/ShrubHub/QikiqtarukHub, https://arcticdata.io/catalog/view/doi:10.18739/A24X0Q, https://arcticdata.io/catalog/view/doi:10.18739/A28Q18, https://arcticdata.io/catalog/view/doi:10.5065/D6542KRH).

Code availability

Code is available in a GitHub repository (https://github.com/ShrubHub/GreeningHub).

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Acknowledgements

We thank the Inuvialuit and Greenlandic People for the opportunity to conduct field research on their land. Data collection on Qikiqtaruk–Herschel Island was funded by the UK Natural Environment Research Council (NERC) NE/M016323/1 (to I.H.M.-S.) and a National Geographic Society grant CP-061R-17 and a Parrot Climate Innovation Grant (to J.T.K.). Data collection at Kangerlussuaq, Greenland was supported by the US National Science Foundation (NSF) grants 0724711, 0713994, 0732168, 0902125, 1107381, 1525636, 1748052 and the National Geographic Society (to E.P.), as well as an Arctic Institute of North America Grant-in-Aid (to C.J.). The sTundra working group was supported by sDiv, the Synthesis Centre of the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig (DFG FZT 118). The Event Drivers of Arctic Browning workshop was funded by P3-Plant Production and Protection (http://p3.sheffield.ac.uk/). Several members of the team are supported by the NASA ABoVE program (https://above.nasa.gov/). Additional funding was provided by the Research Council of Norway grant 287402 (to J.W.B. and H.T.) and 294948 (to F.S., J.W.B., A.B., H.T. and F.-J.W.P.), the NERC doctoral training partnership grant NE/L002558/1 (to J.J.A. and H.J.D.T.), the US NSF grants OPP-15-04134, AGS-15-02150 and OPP-16-03473 (to L.A.-H.), the Natural Sciences and Engineering Research Council of Canada and the Canadian Centennial Scholarship Fund (to S.A.-B.), the Academy of Finland decision 256991 and JPI Climate 291581 (to B.C.F.), the NASA ABoVE grants NNX17AE44G and NNX17AE13G (to S.J.G. and L.T.B.), NSF grants PLR-0632263, PLR-0856516, PLR-1432277, PLR-1504224, PLR-1836839 (to R.D.H.), the US NSF grant PLR-1417745 (to M.M.L.), an NERC IRF NE/L011859/1 (to M.M.-F.), Independent Research Fund Denmark 7027-00133B and Villum Fonden VKR023456 (to S.N.), the Norwegian Research Council grants 230970 and 274711 and the Swedish Research Council registration 2017-05268 (to F.-J.W.P.), University of Zurich Research Priority Program on Global Change and Biodiversity (to G.S.-S.) and the US NSF grants OPP-1108425 and PLR-1108425 (to P.F.S.).

Author information

Author notes

  1. These authors contributed equally: Isla H. Myers-Smith, Jeffrey T. Kerby.

Authors and Affiliations

  1. School of GeoSciences, University of Edinburgh, Edinburgh, UK

    Isla H. Myers-Smith, Jakob J. Assmann, Sandra Angers-Blondin & Haydn J. D. Thomas

  2. Neukom Institute for Computational Science and the Institute of Arctic Studies, Dartmouth College, Hanover, NH, USA

    Jeffrey T. Kerby

  3. Department of Wildlife, Fish, and Conservation Biology, University of California, Davis, CA, USA

    Jeffrey T. Kerby, Christian John & Eric Post

  4. Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK

    Gareth K. Phoenix & Rachael Treharne

  5. Norwegian Institute for Nature Research, FRAM High North Research Centre for Climate and the Environment, Tromsø, Norway

    Jarle W. Bjerke & Hans Tømmervik

  6. Department of Environmental Sciences, University of Virginia, Charlottesville, VA, USA

    Howard E. Epstein

  7. Section for Ecoinformatics and Biodiversity and Arctic Research Center, Department of Bioscience, University of Aarhus, Aarhus C, Denmark

    Jakob J. Assmann & Signe Normand

  8. Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA

    Laia Andreu-Hayles

  9. European Commission, Joint Research Centre, Ispra, Italy

    Pieter S. A. Beck

  10. School of Informatics, Computing and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA

    Logan T. Berner & Scott J. Goetz

  11. Department of Atmospheric Sciences, University of Alaska Fairbanks, Fairbanks, AK, USA

    Uma S. Bhatt

  12. Senckenberg Gesellschaft für Naturforschung, Biodiversity and Climate Research Centre, Frankfurt am Main, Germany

    Anne D. Bjorkman

  13. Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden

    Anne D. Bjorkman

  14. Netherlands Organisation for Scientific Research, The Hague, the Netherlands

    Daan Blok

  15. Natural History Museum, University of Oslo, Oslo, Norway

    Anders Bryn

  16. NORCE Norwegian Research Centre, Bjerknes Center for Climate Research, Bergen, Norway

    Casper T. Christiansen

  17. Systems Ecology, Department of Ecological Science, Vrije Universiteit, Amsterdam, the Netherlands

    J. Hans C. Cornelissen

  18. School of Geography, University of Exeter, Exeter, UK

    Andrew M. Cunliffe

  19. Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA

    Sarah C. Elmendorf

  20. Arctic Centre, University of Lapland, Rovaniemi, Finland

    Bruce C. Forbes

  21. Biology Department, Grand Valley State University, Allendale, MI, USA

    Robert D. Hollister

  22. Department of Geography, University of Zurich, Zurich, Switzerland

    Rogier de Jong

  23. Department of Geography, Colgate University, Hamilton, NY, USA

    Michael M. Loranty

  24. School of Geography and the Environment, University of Oxford, Oxford, UK

    Marc Macias-Fauria

  25. School of Environment, Earth and Ecosystem Sciences, The Open University, Milton Keynes, UK

    Kadmiel Maseyk

  26. Umeå University, Department of Ecology and Environmental Sciences, Umeå, Sweden

    Johan Olofsson

  27. Biological and Environmental Sciences, School of Natural Sciences, University of Stirling, Stirling, UK

    Thomas C. Parker

  28. Department of Geosciences, University of Oslo, Oslo, Norway

    Frans-Jan W. Parmentier & Frode Stordal

  29. Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden

    Frans-Jan W. Parmentier

  30. Department of Arctic and Marine Biology, UiT—The Arctic University of Norway, Tromsø, Norway

    Frans-Jan W. Parmentier

  31. Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland

    Gabriela Schaepman-Strub

  32. Environment and Natural Resources Institute, University of Alaska Anchorage, Anchorage, AK, USA

    Patrick F. Sullivan

  33. Department of Biological Sciences and the Environmental Science and Engineering Program, University of Texas at El Paso, El Paso, TX, USA

    Craig E. Tweedie

  34. Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK, USA

    Donald A. Walker

  35. Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany

    Martin Wilmking

  36. WSL Institute for Snow and Avalanche Research SLF, Team Mountain Ecosystems, Davos Dorf, Switzerland

    Sonja Wipf

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Contributions

I.H.M.-S. and J.T.K. conducted the analyses and wrote the manuscript with contributions from all authors. G.K.P., J.W.B. and H.E.E. contributed substantially to early versions of the manuscript. I.H.M.-S., J.T.K., J.J.A., C.J., S.A.-B., A.M.C., H.J.D.T. and E.P. collected drone and in-situ data. This paper results from two collaborations: the sTundra working group at the German Centre for Integrative Biodiversity Research (iDiv) led by I.H.M.-S., S.C.E. and A.D.B., and the ‘Event Drivers of Arctic Browning Workshop’ at the University of Sheffield led by G.K.P.

Corresponding authors

Correspondence to Isla H. Myers-Smith or Jeffrey T. Kerby.

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The authors declare no competing interests.

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Peer review information Nature Climate Change thanks Matthias Forkel and John Gamon for their contribution to the peer review of this work.

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Myers-Smith, I.H., Kerby, J.T., Phoenix, G.K. et al. Complexity revealed in the greening of the Arctic. Nat. Clim. Chang. 10, 106–117 (2020). https://doi.org/10.1038/s41558-019-0688-1

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