Tropical forests make an approximately neutral contribution to the global carbon cycle, with intact and recovering forests taking in as much carbon as is released through deforestation and degradation. In the near future, tropical forests are likely to become a carbon source, owing to continued forest loss and the effect of climate change on the ability of the remaining forests to capture excess atmospheric carbon dioxide. This will make it harder to limit global warming to below 2 °C. Encouragingly, recent international agreements commit to halting deforestation and degradation, but a lack of fundamental data for use in monitoring and model design makes policy action difficult.
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The author acknowledges partial support from the Natural Environment Research Council (grant NE/R000751/1) and the UK Space Agency (grant Forests 2020).
Nature thanks P. Brando, J. Chave and Y. Malhi for their contribution to the peer review of this work.
The authors declare no competing interests.
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Mitchard, E.T.A. The tropical forest carbon cycle and climate change. Nature 559, 527–534 (2018). https://doi.org/10.1038/s41586-018-0300-2
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