Skip to main content

Thank you for visiting nature.com. 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.

Effects of interannual climate variability on tropical tree cover

Abstract

Climatic warming is substantially intensifying the global water cycle1 and is projected to increase rainfall variability2. Using satellite data, we show that higher climatic variability is associated with reduced tree cover in the wet tropics globally. In contrast, interannual variability in rainfall can have neutral or even positive effects on tree cover in the dry tropics. In South America, tree cover in dry lands is higher in areas with high year-to-year variability in rainfall. This is consistent with evidence from case studies suggesting that in these areas rare wet episodes are essential for opening windows of opportunity where massive tree recruitment can overwhelm disturbance effects, allowing the establishment of extensive woodlands. In Australia, wet extremes have similar effects, but the net effect of rainfall variability is overwhelmed by negative effects of extreme dry years. In Africa, effects of rainfall variability are neutral for dry lands. It is most likely that differences in herbivore communities and fire regimes contribute to regulating tree expansion during wet extremes. Our results illustrate that increasing climatic variability may affect ecosystem services in contrasting, and sometimes surprising, ways. Expansion of dry tropical tree cover during extreme wet events may decrease grassland productivity but enhance carbon sequestration, soil nutrient retention and biodiversity3.

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

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Interactive effects of MAP and the coefficient of interannual variation in rainfall (CV) on tropical tree cover.
Figure 2: Dry-land tree cover response to extreme wet events.
Figure 3: Schematic diagram of the windows of opportunity theory depicting how a climatic pulse may trigger tree cover expansion.

References

  1. Durack, P. J., Wijffels, S. E. & Matear, R. J. Ocean salinities reveal strong global water cycle intensification during 1950 to 2000. Science 336, 455–458 (2012).

    Article  CAS  Google Scholar 

  2. O’Gorman, P. A. O. & Schneider, T. The physical basis for increases in precipitation extremes in simulations of 21st-century climate change. Proc. Natl Acad. Sci. USA 106, 14773–14777 (2009).

    Article  Google Scholar 

  3. Eldridge, D. J. et al. Impacts of shrub encroachment on ecosystem structure and functioning: Towards a global synthesis. Ecol. Lett. 14, 709–782 (2011).

    Article  Google Scholar 

  4. Hirota, M., Holmgren, M., Van Nes, E. H. & Scheffer, M. Global resilience of tropical forest and savanna to critical transitions. Science 334, 232–235 (2011).

    Article  CAS  Google Scholar 

  5. Staver, A. C., Archibald, S. & Levin, S. A. The global extent and determinants of savanna and forest as alternative biome states. Science 334, 230–232 (2011).

    Article  CAS  Google Scholar 

  6. Scheffer, M., Carpenter, S., Foley, J. A., Folke, C. & Walker, B. Catastrophic shifts in ecosystems. Nature 413, 591–596 (2001).

    Article  CAS  Google Scholar 

  7. Scheffer, M. et al. Early-warning signals for critical transitions. Nature 461, 53–59 (2009).

    Article  CAS  Google Scholar 

  8. Malhi, Y. & Wright, J. Spatial patterns and recent trends in the climate of tropical rainforest regions. Phil. Trans. R. Soc. Lond. B 359, 311–329 (2004).

    Article  Google Scholar 

  9. Holmgren, M., Scheffer, M., Ezcurra, E., Gutiérrez, J. R. & Mohren, G. M. J. El Niño effects on the dynamics of terrestrial ecosystems. Trends Ecol. Evol. 16, 89–94 (2001).

    Article  CAS  Google Scholar 

  10. Holmgren, M. et al. Extreme climatic events shape arid and semiarid ecosystems. Front. Ecol. Environ. 4, 87–95 (2006).

    Article  Google Scholar 

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

    Article  Google Scholar 

  12. Austin, M. P. & Williams, O. B. Influence of climate and community composition on the population demography of pasture species in semi-arid Australia. Vegetatio 43–49 (1988).

  13. Holmgren, M., López, B. C., Gutiérrez, J. R. & Squeo, F. A. Herbivory and plant growth rate determine the success of El Niño Southern Oscillation-driven tree establishment in semiarid South America. Glob. Change Biol. 12, 2263–2271 (2006).

    Article  Google Scholar 

  14. Sitters, J., Holmgren, M., Stoorvogel, J. J. & López, B. C. Rainfall-tuned management facilitates dry forest recovery. Restor. Ecol. 20, 33–42 (2012).

    Article  Google Scholar 

  15. Good, S. P. & Caylor, K. K. Climatological determinants of woody cover in Africa. Proc. Natl Acad. Sci. USA 108, 4902–4907 (2011).

    Article  CAS  Google Scholar 

  16. Murphy, B. P. & Bowman, D. M. J. S. What controls the distribution of tropical forest and savanna? Ecol. Lett. 15, 748–758 (2012).

    Article  Google Scholar 

  17. Holmgren, M. & Scheffer, M. El Niño as a window of opportunity for the restoration of degraded arid ecosystems. Ecosystems 4, 151–159 (2001).

    Article  Google Scholar 

  18. Scheffer, M., Van Nes, E. H., Holmgren, M. & Hughes, T. Pulse-driven loss of top-down control: The critical-rate hypothesis. Ecosystems 11, 226–237 (2008).

    Article  Google Scholar 

  19. Bond, W. J. What limits trees in C4 grasslands and savannas? Annu. Rev. Ecol. Evol. Syst. 39, 641–659 (2008).

    Article  Google Scholar 

  20. Fensham, R. J., Fairfax, R. J. & Ward, D. P. Drought-induced tree death in savanna. Glob. Change Biol. 15, 380–387 (2009).

    Article  Google Scholar 

  21. Camberlin, P., Martiny, N., Philippon, N. & Richard, Y. Determinants of the interannual relationships between remote sensed photosynthetic activity and rainfall in tropical Africa. Remote Sens. Environ. 106, 199–216 (2007).

    Article  Google Scholar 

  22. De Vivo, M. & Carmignotto, A. P. Holocene vegetation change and the mammal faunas of South America and Africa. J. Biogeogr. 31, 943–957 (2004).

    Article  Google Scholar 

  23. Prins, H. H. T. & Van der Jeugd, H. Herbivore population crashes and woodland structure in East Africa. J. Ecol. 81, 305–314 (1993).

    Article  Google Scholar 

  24. Tews, J., Schurr, F. & Jeltsch, F. Seed dispersal by cattle may cause shrub encroachment of Grewia flava on southern Kalahari rangelands. Appl. Veget. Sci. 7, 89–102 (2004).

    Article  Google Scholar 

  25. Sankaran, M. et al. Determinants of woody cover in African savannas. Nature 438, 846–849 (2005).

    Article  CAS  Google Scholar 

  26. Hoffmann, W. A. et al. Ecological thresholds at the savanna-forest boundary: How plant traits, resources and fire govern the distribution of tropical biomes. Ecol. Lett. 15, 759–768 (2012).

    Article  Google Scholar 

  27. Dormann, C. F. et al. Methods to account for spatial autocorrelation in the analysis of species distributional data: A review. Ecography 30, 609–628 (2007).

    Article  Google Scholar 

  28. Hansen, M. C. et al. Global percent tree cover at a spatial resolution of 500 meters: First results of the MODIS vegetation continuous fields algorithm. Earth Inter. 7, 1–15 (2003).

    Article  Google Scholar 

  29. Mitchell, T. D. & Jones, P. D. An improved method of constructing a database of monthly climate observations and associated high-resolution grids. Int. J. Climatol. 25, 693–712 (2005).

    Article  Google Scholar 

  30. McKee, T. B., Doesken, N. J. & Kliest, J. in Proc. 8th Conf. Appl. Climatol. Vol. 17, 179–184 (American Meteorological Society, 1993).

  31. Markham, C. G. Seasonality of precipitation in the United States. Ann. Assoc. Amer. Geograph. 60, 593–597 (1970).

    Article  Google Scholar 

  32. Cleveland, W. S. Robust locally weighted regression and smoothing scatterplots. J. Am. Stat. Assoc. 368, 829–836 (1979).

    Article  Google Scholar 

  33. Holmgren, M. in New Models for Ecosystem Dynamics and Restoration (eds Hobbs, R. J. & Suding, K. N.) 112–123 (Island Press, 2009).

    Google Scholar 

Download references

Acknowledgements

This research was partly financially supported by the ERC-Early Warning grant and Spinoza award received by M.S. We thank C. J. F. Ter Braak for insightful discussions on the statistical approaches taken and G. Mazzochini for advice on spatial linear modelling. The data reported in this paper are extracted as described in the supporting online material from the publicly available sites of MODIS (http://www.glcf.umd.edu/data/vcf/) and CRU (http://www.cru.uea.ac.uk/cru/data/hrg/).

Author information

Authors and Affiliations

Authors

Contributions

M. Holmgren and M.S. conceived and wrote the paper. M. Hirota collected the data. All authors analysed and interpreted the data, and revised the manuscript.

Corresponding author

Correspondence to Milena Holmgren.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Holmgren, M., Hirota, M., van Nes, E. et al. Effects of interannual climate variability on tropical tree cover. Nature Clim Change 3, 755–758 (2013). https://doi.org/10.1038/nclimate1906

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nclimate1906

This article is cited by

Search

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