The projected timing of climate departure from recent variability


Ecological and societal disruptions by modern climate change are critically determined by the time frame over which climates shift beyond historical analogues. Here we present a new index of the year when the projected mean climate of a given location moves to a state continuously outside the bounds of historical variability under alternative greenhouse gas emissions scenarios. Using 1860 to 2005 as the historical period, this index has a global mean of 2069 (±18 years s.d.) for near-surface air temperature under an emissions stabilization scenario and 2047 (±14 years s.d.) under a ‘business-as-usual’ scenario. Unprecedented climates will occur earliest in the tropics and among low-income countries, highlighting the vulnerability of global biodiversity and the limited governmental capacity to respond to the impacts of climate change. Our findings shed light on the urgency of mitigating greenhouse gas emissions if climates potentially harmful to biodiversity and society are to be prevented.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Estimating the projected timing of climate departure from recent variability.
Figure 2: The projected timing of climate departure from recent variability.
Figure 3: The projected timing of climate departure from recent variability in global biodiversity hotspots.
Figure 4: Biodiversity hotspots: exposure to climate departures, and economic capacity to respond.
Figure 5: Susceptibility of societies to climate departures, and economic capacity to respond.


  1. 1

    Reilly, J. & Schimmelpfennig, D. Irreversibility, Uncertainty, and Learning: Portraits of Adaptation to Long-term Climate Change (Springer, 2000)

    Google Scholar 

  2. 2

    Alley, R. B. et al. Abrupt climate change. Science 299, 2005–2010 (2003)

    CAS  ADS  Article  Google Scholar 

  3. 3

    Williams, J. W. & Jackson, S. T. Novel climates, no-analog communities and ecological surprises. Front. Ecol. Environ 5, 475–482 (2007)

    Article  Google Scholar 

  4. 4

    Peterson, A. T., Soberon, J., Pearson, R. G. & Martinez-Meyer, E. Ecological Niches and Geographic Distributions (Monographs in Population Biology Vol. 49) (Princeton Univ. Press, 2011)

    Google Scholar 

  5. 5

    Doney, S. C. et al. Climate change impacts on marine ecosystems. Annu. Rev. Mar. Sci. 4, 11–37 (2012)

    ADS  Article  Google Scholar 

  6. 6

    Parmesan, C. & Yohe, G. A globally coherent fingerprint of climate change impacts across natural systems. Nature 421, 37–42 (2003)

    CAS  ADS  Article  Google Scholar 

  7. 7

    Chen, I.-C., Hill, J. K., Ohlemüller, R., Roy, D. B. & Thomas, C. D. Rapid range shifts of species associated with high levels of climate warming. Science 333, 1024–1026 (2011)

    CAS  ADS  Article  Google Scholar 

  8. 8

    Parmesan, C. Ecological and evolutionary responses to recent climate change. Annu. Rev. Ecol. Evol. Syst. 37, 637–669 (2006)

    Article  Google Scholar 

  9. 9

    Thomas, C. D., Franco, A. M. A. & Hill, J. K. Range retractions and extinction in the face of climate warming. Trends Ecol. Evol. 21, 415–416 (2006)

    Article  Google Scholar 

  10. 10

    Crowley, T. J. & North, G. R. Abrupt climate change and extinction events in Earth history. Science 240, 996–1002 (1988)

    CAS  ADS  Article  Google Scholar 

  11. 11

    Mora, C. & Zapata, F. A. in The Balance of Nature and Human Impact (ed. K. Rohde ) 239–257 (Cambridge Univ. Press, 2013)

    Google Scholar 

  12. 12

    Berg, M. P. et al. Adapt or disperse: understanding species persistence in a changing world. Glob. Change Biol. 16, 587–598 (2010)

    ADS  Article  Google Scholar 

  13. 13

    Lobell, D. B. & Gourdji, S. M. The influence of climate change on global crop productivity. Plant Physiol. 160, 1686–1697 (2012)

    CAS  Article  Google Scholar 

  14. 14

    Zhang, X. & Cai, X. Climate change impacts on global agricultural water deficit. Geophys. Res. Lett. 40, 1111–1117 (2013)

    ADS  Article  Google Scholar 

  15. 15

    Taylor, R. G. et al. Ground water and climate change. Nature Clim. Change 3, 322–329 (2013)

    ADS  Article  Google Scholar 

  16. 16

    Patz, J. A. & Olson, S. H. Climate change and health: global to local influences on disease risk. Ann. Trop. Med. Parasitol. 100, 535–549 (2006)

    CAS  Article  Google Scholar 

  17. 17

    Epstein, P. R. Climate change and infectious disease: stormy weather ahead? Epidemiology 13, 373–375 (2002)

    Article  Google Scholar 

  18. 18

    Khasnis, A. A. & Nettleman, M. D. Global warming and infectious disease. Arch. Med. Res. 36, 689–696 (2005)

    Article  Google Scholar 

  19. 19

    Sherwood, S. C. & Huber, M. An adaptability limit to climate change due to heat stress. Proc. Natl Acad. Sci. USA 107, 9552–9555 (2010)

    CAS  ADS  Article  Google Scholar 

  20. 20

    Berry, H., Bowen, K. & Kjellstrom, T. Climate change and mental health: a causal pathways framework. Int. J. Public Health 55, 123–132 (2010)

    Article  Google Scholar 

  21. 21

    Díaz, S., Fargione, J., Chapin, F. S. & Tilman, D. Biodiversity loss threatens human well-being. PLoS Biol. 4, e277 (2006)

    Article  Google Scholar 

  22. 22

    Tol, R. S. Estimates of the damage costs of climate change. Part 1. Benchmark estimates. Environ. Resour. Econ. 21, 47–73 (2002)

    Article  Google Scholar 

  23. 23

    Kloor, K. The war against warming. Nature Rep. Clim. Change 3, 145–146, (2009)

    Article  Google Scholar 

  24. 24

    Williams, J. W., Jackson, S. T. & Kutzbach, J. E. Projected distributions of novel and disappearing climates by 2100 AD. Proc. Natl Acad. Sci. USA 104, 5738–5742 (2007)

    CAS  ADS  Article  Google Scholar 

  25. 25

    Solomon, S. et al. (eds). Climate Change: The Physical Science Basis. Summary for Policymakers (Cambridge Univ. Press, 2007)

  26. 26

    Taylor, K. E., Stouffer, R. J. & Meehl, G. A. An overview of CMIP5 and the experiment design. Bull. Am. Meteorol. Soc. 93, 485–498 (2012)

    ADS  Article  Google Scholar 

  27. 27

    Vuuren, D. P. et al. The representative concentration pathways: an overview. Clim. Change 109, 5–31 (2011)

    ADS  Article  Google Scholar 

  28. 28

    Meinshausen, M. et al. The RCP greenhouse gas concentrations and their extensions from 1765 to 2300. Clim. Change 109, 213–241 (2011)

    CAS  ADS  Article  Google Scholar 

  29. 29

    van Vliet, J., den Elzen, M. G. & van Vuuren, D. P. Meeting radiative forcing targets under delayed participation. Energy Econ. 31, S152–S162 (2009)

    Article  Google Scholar 

  30. 30

    Raven, J. A. et al. (eds). Ocean Acidification due to Increasing Atmospheric Carbon Dioxide (Royal Society, 2005)

  31. 31

    Zeebe, R. E., Zachos, J. C., Caldeira, K. & Tyrrell, T. Carbon emissions and acidification. Science 321, 51–52 (2008)

    CAS  Article  Google Scholar 

  32. 32

    Rockstrom, J. et al. A safe operating space for humanity. Nature 461, 472–475 (2009)

    ADS  Article  Google Scholar 

  33. 33

    Gaston, K. J. Global patterns in biodiversity. Nature 405, 220–227 (2000)

    CAS  Article  Google Scholar 

  34. 34

    Deutsch, C. A. et al. Impacts of climate warming on terrestrial ectotherms across latitude. Proc. Natl Acad. Sci. USA 105, 6668–6672 (2008)

    CAS  ADS  Article  Google Scholar 

  35. 35

    Colwell, R. K., Brehm, G., Cardelús, C. L., Gilman, A. C. & Longino, J. T. Global warming, elevational range shifts, and lowland biotic attrition in the wet tropics. Science 322, 258–261 (2008)

    CAS  ADS  Article  Google Scholar 

  36. 36

    Hoegh-Guldberg, O. Climate change, coral bleaching and the future of the world’s coral reefs. Mar. Freshw. Res. 50, 839–866 (1999)

    Google Scholar 

  37. 37

    Baker, A. C., Glynn, P. W. & Riegl, B. Climate change and coral reef bleaching: An ecological assessment of long-term impacts, recovery trends and future outlook. Estuar. Coast. Shelf Sci. 80, 435–471 (2008)

    ADS  Article  Google Scholar 

  38. 38

    Tittensor, D. P. et al. Global patterns and predictors of marine biodiversity across taxa. Nature 466, 1098–1101 (2010)

    CAS  ADS  Article  Google Scholar 

  39. 39

    Chown, S. L., Gaston, K. J. & Williams, P. H. Global patterns in species richness of pelagic seabirds: the Procellariiformes. Ecography 21, 342–350 (1998)

    Article  Google Scholar 

  40. 40

    La Sorte, F. A. & Jetz, W. Tracking of climatic niche boundaries under recent climate change. J. Anim. Ecol. 81, 914–925 (2012)

    Article  Google Scholar 

  41. 41

    Sorte, C. J. B. Predicting persistence in a changing climate: flow direction and limitations to redistribution. Oikos 122, 161–170 (2013)

    Article  Google Scholar 

  42. 42

    Devictor, V. et al. Differences in the climatic debts of birds and butterflies at a continental scale. Nature Clim. Change 2, 121–124 (2012)

    ADS  Article  Google Scholar 

  43. 43

    Zhu, K., Woodall, C. W. & Clark, J. S. Failure to migrate: lack of tree range expansion in response to climate change. Glob. Change Biol. 18, 1042–1052 (2012)

    ADS  Article  Google Scholar 

  44. 44

    Angert, A. L. et al. Do species’ traits predict recent shifts at expanding range edges? Ecol. Lett. 14, 677–689 (2011)

    Article  Google Scholar 

  45. 45

    Baird, A. & Maynard, J. A. Coral adaptation in the face of climate change. Science 320, 315–316 (2008)

    CAS  Article  Google Scholar 

  46. 46

    Pandolfi, J. M., Connolly, S. R., Marshall, D. J. & Cohen, A. L. Projecting coral reef futures under global warming and ocean acidification. Science 333, 418–422 (2011)

    CAS  ADS  Article  Google Scholar 

  47. 47

    Allen, C. D. et al. A global overview of drought and heat-induced tree mortality reveals emerging climate change risks for forests. For. Ecol. Manage. 259, 660–684 (2010)

    Article  Google Scholar 

  48. 48

    Carey, C. & Alexander, M. A. Climate change and amphibian declines: is there a link? Divers. Distrib. 9, 111–121 (2003)

    Article  Google Scholar 

  49. 49

    McKechnie, A. E. & Wolf, B. O. Climate change increases the likelihood of catastrophic avian mortality events during extreme heat waves. Biol. Lett. 6, 253–256 (2010)

    Article  Google Scholar 

  50. 50

    Mora, C. & Sale, P. Ongoing global biodiversity loss and the need to move beyond protected areas: a review of the technical and practical shortcomings of protected areas on land and sea. Mar. Ecol. Prog. Ser. 434, 251–266 (2011)

    ADS  Article  Google Scholar 

  51. 51

    Kier, G. et al. A global assessment of endemism and species richness across island and mainland regions. Proc. Natl Acad. Sci. USA 106, 9322–9327 (2009)

    CAS  ADS  Article  Google Scholar 

Download references


We thank D. Beilman for commenting on the paper; E. Wingert for help on the figures; D. Olsen for technical support; H. Kreft and the International Union for Conservation of Nature, BirdLife International, the Food and Agriculture Organization of the United Nations, the World Bank Database, the National Centers for Environmental Prediction, the World Database of Protected Areas, and the Gridded Human Population of the World Database for making their data openly available. We acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP5, and we thank the climate modelling groups (listed in Extended Data Table 1) for producing and making available their model outputs. This work was made possible by funding from the University of Hawai‘i Sea Grant to C.M. The paper was developed as part of the graduate course on ‘Methods for Large Scale Analyses’ in the Department of Geography, University of Hawai‘i at Mānoa. A.G.F. and T.W.G were supported by Pacific Islands Climate Change Cooperative (PICCC) award F10AC00077 and National Science Foundation Hawai‘i EPSCoR grant no. EPS-0903833. R.J.L. was supported by the Pacific Islands Climate Science Center and PICCC award F10A00079. R.S.D. and E.J.T. were supported by National Science Foundation Graduate Fellowships, and I.F.-S. by a postdoctoral fellowship from the Japanese Society for the Promotion of Science.

Author information




All authors contributed equally to conceive the study, compile the data, conduct analyses, and write the manuscript.

Corresponding author

Correspondence to Camilo Mora.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Extended data figures and tables

Extended Data Figure 1 Evaluating robustness of Earth System Models.

ac, Analysis of near-surface air temperature. df, Analysis of sea surface temperature. a, d, Normalized Taylor diagrams. The Taylor diagrams compare actual observations with CMIP5 model simulations, and summarize three different metrics of similitude: the correlation (curved axis), the ratio of the standard deviations (x and y axes) and the root mean squared error (blue arcs). Blue points indicate perfect fit, red points the multi-model average, and black points the comparison of each Earth System Model to actual observations. The closer a red or black point is to the blue point, the better the fit between actual and simulated data. b, c, e, f, Comparison between actual and multi-model minimum (b, e) and maximum (c, f) temperatures for the 20-year period 1986–2005 (the time frame for which actual observations were mostly available). Dashed lines indicate the 1:1 relationship.

Extended Data Figure 2 Multi-model uncertainty in the projected timing of climate departure.

Results are shown for near-surface air temperature (a), sea surface temperature (b), evaporation (c), sensible heat flux (d), ocean surface pH (e), precipitation (f) and transpiration (g). Maps on the left show the mean year of climate departure under RCP85, and maps on the right illustrate the spatial patterns of inter-model standard error of the mean for RCP85. The histograms on the right indicate the frequency of grid cells by multi-model standard error of the mean according to each emissions scenario (blue, RCP45; red, RCP85).

Extended Data Figure 3 Sea surface temperature and projected timing of climate departure.

a, b, Projected year when annual (a) or monthly (b) sea surface temperature means move to a state continuously outside annual or monthly historical bounds, respectively. c, Absolute change in mean annual sea surface temperature. (Results in ac are based on RCP85.) d, Cumulative frequency of 100-km resolution grid cells according to the year of climate departure under the two emissions scenarios and for mean annual and monthly sea surface temperature. e, Scatter plot relating the grid cells from the absolute change map (c) to the same grid cells from the projected timing of climate departure map (a).

Extended Data Figure 4 Projected timing of climate departure for different climate variables.

We calculated the year of climate departure for five variables in addition to temperature. We considered the year of climate departure as the year at which the first variable exceeded its historical bounds of variability. The plots show the year of climate departure (left), the absolute change (middle) and the relation between the departure year and absolute change (right) under RCP85. The plot at the bottom right compares the global average year using temperature alone with the year when considering additional climate variables. Vertical lines indicate s.d.

Extended Data Figure 5 Biodiversity hotspots.

Global patterns of species richness were mapped for 13 marine and terrestrial taxa. For each taxon, we outlined biodiversity hotspots as the top 10% most species-rich places on Earth where the given taxon occurred (bold black lines). For mammals, birds, reptiles, amphibians, marine fishes, cephalopods, corals, mangroves and seagrasses (ah, jm), we used expert-verified geographical ranges to map patterns of species richness by counting the number of species whose ranges overlapped with an equal-area grid with a resolution of 100 km. i, For terrestrial vascular plants we used the number of species in different regions (data from ref. 51) and calculated species richness as the highest number of species occurring in the regions intersecting each 100-km resolution grid cell. The number of species or species richness used for each taxonomic group is indicated in parentheses.

Extended Data Figure 6 Average gross domestic product (US$) per person for countries where the world’s biodiversity hotspots are located.

Horizontal bars represent the average GDP per person for the countries containing the hotspots for the 13 taxa examined.

Extended Data Table 1 Earth System Models analysed
Extended Data Table 2 Data sources

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Mora, C., Frazier, A., Longman, R. et al. The projected timing of climate departure from recent variability. Nature 502, 183–187 (2013).

Download citation

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


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