Greening of the land surface in the world’s cold regions consistent with recent warming


Global ecosystem function is highly dependent on climate and atmospheric composition, yet ecosystem responses to environmental changes remain uncertain. Cold, high-latitude ecosystems in particular have experienced rapid warming1, with poorly understood consequences2,3,4. Here, we use a satellite-observed proxy for vegetation cover—the fraction of absorbed photosynthetically active radiation5—to identify a decline in the temperature limitation of vegetation in global ecosystems between 1982 and 2012. We quantify the spatial functional response of maximum annual vegetation cover to temperature and show that the observed temporal decline in temperature limitation is consistent with expectations based on observed recent warming. An ensemble of Earth system models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) mischaracterized the functional response to temperature, leading to a large overestimation of vegetation cover in cold regions. We identify a 16.4% decline in the area of vegetated land that is limited by temperature over the past three decades, and suggest an expected large decline in temperature limitation under future warming scenarios. This rapid observed and expected decline in temperature limitation highlights the need for an improved understanding of other limitations to vegetation growth in cold regions3,4,6, such as soil characteristics, species migration, recruitment, establishment, competition and community dynamics.

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Fig. 1: Spatial relationship between temperature and vegetation cover.
Fig. 2: Changes in temperature limitation.
Fig. 3: Observed and predicted changes in F95.
Fig. 4: Current and predicted changes in the relative spatial extent of temperature-limited area of vegetated land.
Fig. 5: ESM estimates of the relationship between maximum vegetation cover and temperature.


  1. 1.

    Pithan, F. & Mauritsen, T. Arctic amplification dominated by temperature feedbacks in contemporary climate models. Nat. Geosci. 7, 181–184 (2014).

    Article  CAS  Google Scholar 

  2. 2.

    Zeng, Z. et al. Climate mitigation from vegetation biophysical feedbacks during the past three decades. Nat. Clim. Change 7, 432–436 (2017).

    Article  Google Scholar 

  3. 3.

    Epstein, H. E. et al. Dynamics of aboveground phytomass of the circumpolar Arctic tundra during the past three decades. Environ. Res. Lett. 7, 015506 (2012).

    Article  Google Scholar 

  4. 4.

    Elmendorf, S. C. et al. Plot-scale evidence of tundra vegetation change and links to recent summer warming. Nat. Clim. Change 2, 453–457 (2012).

    Article  Google Scholar 

  5. 5.

    Zhu, Z. et al. Global data sets of vegetation leaf area index (LAI)3g and fraction of photosynthetically active radiation (FPAR)3g derived from global inventory modeling and mapping studies (GIMMS) normalized difference vegetation index (NDVI3g) for the period 1981 to 2011. Remote Sens. 5, 927–948 (2013).

    Article  Google Scholar 

  6. 6.

    Myers-Smith, I. H. et al. Climate sensitivity of shrub growth across the tundra biome. Nat. Clim. Change 5, 887–891 (2015).

    Article  Google Scholar 

  7. 7.

    Myneni, R. B. et al. Increased plant growth in the northern high latitudes from 1981 to 1991. Nature 386, 698–702 (1997).

    Article  CAS  Google Scholar 

  8. 8.

    Zhu, Z. et al. Greening of the Earth and its drivers. Nat. Clim. Change 6, 791–795 (2016).

    Article  CAS  Google Scholar 

  9. 9.

    De Jong, R., de Bruin, S., de Wit, A., Schaepman, M. E. & Dent, D. L. Analysis of monotonic greening and browning trends from global NDVI time-series. Remote Sens. Environ. 115, 692–702 (2011).

    Article  Google Scholar 

  10. 10.

    Los, S. O. Analysis of trends in fused AVHRR and MODIS NDVI data for 1982-2006: indication for a CO2 fertilization effect in global vegetation. Glob. Biogeochem. Cycles 27, 318–330 (2013).

    Article  CAS  Google Scholar 

  11. 11.

    Mao, J. et al. Human-induced greening of the northern extratropical land surface. Nat. Clim. Change 6, 959–963 (2016).

    Article  Google Scholar 

  12. 12.

    Forzieri, G., Alkama, R., Miralles, D. G. & Cescatti, A. Satellites reveal contrasting responses of regional climate to the widespread greening of Earth. Science 356, 1180–1184 (2017).

    Article  CAS  Google Scholar 

  13. 13.

    Keenan, T. F. et al. Recent pause in the growth rate of atmospheric CO2 due to enhanced terrestrial carbon uptake. Nat. Commun. 7, 13428 (2016).

    Article  CAS  Google Scholar 

  14. 14.

    Zhu, Z. et al. Attribution of seasonal leaf area index trends in the northern latitudes with ‘optimally’ integrated ecosystem models. Glob. Change Biol. 23, 4798–4813 (2017).

    Article  Google Scholar 

  15. 15.

    Anav, A. et al. Evaluation of land surface models in reproducing satellite derived leaf area index over the high-latitude northern hemisphere. Part II: Earth system models. Remote Sens. 5, 3637–3661 (2013).

    Article  Google Scholar 

  16. 16.

    Mahowald, N. et al. Projections of leaf area index in Earth system models. Earth Syst. Dynam. 7, 211–229 (2016).

    Article  Google Scholar 

  17. 17.

    Murray-Tortarolo, G. et al. Evaluation of land surface models in reproducing satellite-derived LAI over the high-latitude northern hemisphere. Part I: uncoupled DGVMs. Remote Sens. 5, 4819–4838 (2013).

    Article  Google Scholar 

  18. 18.

    Le Quéré, C. et al. Global carbon budget 2016. Earth Syst. Sci. Data 8, 605–649 (2016).

    Article  Google Scholar 

  19. 19.

    Ukkola, A. M. et al. Reduced streamflow in water-stressed climates consistent with CO2 effects on vegetation. Nat. Clim. Change 6, 75–78 (2015).

    Article  Google Scholar 

  20. 20.

    Donohue, R. J., Roderick, M. L., McVicar, T. R. & Farquhar, G. D. Impact of CO2 fertilization on maximum foliage cover across the globe’s warm, arid environments. Geophys. Res. Lett. 40, 3031–3035 (2013).

    Article  CAS  Google Scholar 

  21. 21.

    Myneni, R. B. & Williams, D. L. On the relationship between FAPAR and NDVI. Remote Sens. Environ. 49, 200–211 (1994).

    Article  Google Scholar 

  22. 22.

    Barichivich, J. et al. Temperature and snow-mediated moisture controls of summer photosynthetic activity in northern terrestrial ecosystems between 1982 and 2011. Remote Sens. 6, 1390–1431 (2014).

    Article  Google Scholar 

  23. 23.

    Huang, M. et al. Velocity of change in vegetation productivity over northern high latitudes. Nat. Ecol. Evol. 1, 1649–1654 (2017).

    Article  Google Scholar 

  24. 24.

    Burrows, M. T. et al. Geographical limits to species-range shifts are suggested by climate velocity. Nature 507, 492–495 (2014).

    Article  CAS  Google Scholar 

  25. 25.

    Tian, F. et al. Evaluating temporal consistency of long-term global NDVI datasets for trend analysis. Remote Sens. Environ. 163, 326–340 (2015).

    Article  Google Scholar 

  26. 26.

    Rogers, A. et al. Terrestrial biosphere models underestimate photosynthetic capacity and CO2 assimilation in the Arctic. New Phytol. 216, 1090–1103 (2017).

    Article  CAS  Google Scholar 

  27. 27.

    Arft, A. M. et al. Responses of tundra plants to experimental warming: a meta-analysis of the International Tundra Experiment. Ecol. Monogr. 69, 491–511 (1999).

    Google Scholar 

  28. 28.

    Jia, G. J., Epstein, H. E. & Walker, D. A. Spatial heterogeneity of tundra vegetation response to recent temperature changes. Glob. Change Biol. 12, 42–55 (2006).

    Article  Google Scholar 

  29. 29.

    Bhatt, U. S. et al. Changing seasonality of panarctic tundra vegetation in relationship to climatic variables. Environ. Res. Lett. 12, 055003 (2017).

    Article  Google Scholar 

  30. 30.

    Mekonnen, Z. A., Riley, W. J. & Grant, R. F. 21st century tundra shrubification could enhance net carbon uptake of North America Arctic tundra under an RCP8.5 climate trajectory. Environ. Res. Lett. 13, 054029 (2018).

    Article  Google Scholar 

  31. 31.

    Koven, C. D., Lawrence, D. M. & Riley, W. J. Permafrost carbon−climate feedback is sensitive to deep soil carbon decomposability but not deep soil nitrogen dynamics. Proc. Natl Acad. Sci. USA 112, 3752–3757 (2015).

    CAS  Google Scholar 

  32. 32.

    Harris, I., Jones, P. D., Osborn, T. J. & Lister, D. H. Updated high-resolution grids of monthly climatic observations—the CRU TS3.10 dataset. Int. J. Climatol. 34, 623–642 (2014).

    Article  Google Scholar 

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The authors are very grateful to the University of East Anglia Climatic Research Unit for providing the climate data used in this study, the CMIP5 project and ESG Federation for making ESM simulations publicly available, and the Vegetation Remote Sensing and Climate Research group at Boston University for making the satellite fAPAR data available. T.F.K. acknowledges support from NASA Terrestrial Ecology Program IDS Award NNH17AE86I. T.F.K. and W.J.R. were supported by the Director, Office of Science, Office of Biological and Environmental Research of the US Department of Energy under contract DE-AC02-05CH11231 as part of the Reducing Uncertainty in Biogeochemical Interactions through Synthesis and Computation Scientific Focus Area. We thank M. Torn for discussions on the interpretation and implication of the results, and A. Ukkola and I. C. Prentice for early methodological discussions.

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T.F.K. designed and performed the analysis and led the drafting of the manuscript. W.J.R. contributed analysis ideas and participated in drafting the manuscript.

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Correspondence to T. F. Keenan.

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Keenan, T.F., Riley, W.J. Greening of the land surface in the world’s cold regions consistent with recent warming. Nature Clim Change 8, 825–828 (2018).

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