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Recent trends in African fires driven by cropland expansion and El Niño to La Niña transition

Nature Climate Change volume 4, pages 791795 (2014) | Download Citation

Abstract

Landscape fires are key in African ecosystems1,2,3 and the continent is responsible for 70% of global burned area and 50% of fire-related carbon emissions4,5. Fires are mostly human ignited, but precipitation patterns govern when and where fires can occur6. The relative role of humans and precipitation in driving the spatio-temporal variability in burned area is not fully disentangled but is required to predict future burned area7,8. Over 2001–2012, observations indicate strong but opposing trends in the African hemispheres4. Here we use satellite data and statistical modelling and show that changes in precipitation, driven by the El Niño/Southern Oscillation (ENSO), which changed from El Niño to La Niña dominance over our study period, contributed substantially (51%) to the upward trend over southern Africa. This also contributed to the downward trend over northern Africa (24%), but here rapid demographic and socio-economic changes were almost as important (20%), mainly due to conversion of savannah into cropland, muting burned area. Given the economic perspective of Africa and the oscillative nature of ENSO, future African savannah burned area will probably decline. Combined with increasing global forest fire activity due to climate change9,10,11, our results indicate a potential shift in global pyrogeography from being savannah dominated to being forest dominated.

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Acknowledgements

We would like to thank P. Castellanos and A. Meesters for their helpful suggestions and all data providers and agencies for making their data publicly available. N.A. received financial support from the EU FP7 MACC-II project (contract number 218793) and G.R.v.d.W. is supported by the European Research Council (contract number 280061).

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Affiliations

  1. Earth and Climate Cluster, Department of Earth Sciences, Faculty of Earth and Life Sciences, VU University, De Boelelaan 1085, 1081HV, Amsterdam, The Netherlands

    • Niels Andela
    •  & Guido R. van der Werf

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Contributions

N.A. and G.R.v.d.W. designed the research, N.A. conducted the research, and N.A. and G.R.v.d.W. wrote the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Niels Andela.

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DOI

https://doi.org/10.1038/nclimate2313