Planetary warming may be exacerbated if it accelerates loss of soil carbon to the atmosphere. This carbon-cycle–climate feedback is included in climate projections. Yet, despite ancillary data supporting a positive feedback, there is limited evidence for soil carbon loss under warming. The low confidence engendered in feedback projections is reduced further by the common representation in models of an outdated knowledge of soil carbon turnover. 'Model-knowledge integration' — representing in models an advanced understanding of soil carbon stabilization — is the first step to build confidence. This will inform experiments that further increase confidence by resolving competing mechanisms that most influence projected soil-carbon stocks. Improving feedback projections is an imperative for establishing greenhouse gas emission targets that limit climate change.
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This work was supported by grants from the US National Science Foundation (DEB-1021098 and DEB-1457614). M.A.B. was supported by The Royal Netherlands Academy of Arts and Sciences (Visiting Professors Programme); T.W.C. was supported by the Yale Climate and Energy Institute and a Marie Skłodowska Curie Fellowship; and W.R.W. was supported by grants from the US Department of Agriculture (NIFA 2015-67003-23485) and the US Department of Energy (TES DE-SC0014374). Thanks to W.v.d.P. and F.C. for comments on an earlier draft of this script.
The authors declare no competing financial interests.
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Bradford, M., Wieder, W., Bonan, G. et al. Managing uncertainty in soil carbon feedbacks to climate change. Nature Clim Change 6, 751–758 (2016). https://doi.org/10.1038/nclimate3071
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