Sources & further reading

How figures are used here

• Every number on this site is taken from one of the sources below, in that source’s own terms and units, with the source named beside it.
• Each source is labelled as an IPCC assessment, an independent peer-reviewed paper, or a peer-reviewed synthesis that feeds into IPCC assessments.
• Where sources disagree, both ends of the range are shown and both are cited. Unit conversions we made ourselves are footnoted.
• Global estimates carry real uncertainty and are revised over time. Please read the original work before relying on any figure.

References

1. Canadell, J.G., Monteiro, P.M.S., et al. (2021). Global Carbon and Other Biogeochemical Cycles and Feedbacks. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the IPCC, pp. 673–816. Cambridge University Press. doi:10.1017/9781009157896.007

   Type: IPCC assessment (AR6 WGI, Chapter 5). Checked against: Full text (Chapter 5 PDF): Table 5.1 and section 5.2.1.5, pp. 699–700.

2. Friedlingstein, P., O’Sullivan, M., Jones, M.W., Andrew, R.M., et al. (2025). Global Carbon Budget 2024. Earth System Science Data, 17, 965–1039. doi:10.5194/essd-17-965-2025

   Type: peer-reviewed community synthesis (not independent of IPCC AR6). Checked against: Abstract and full text (sections on the land sink and LULUCF).

3. Field, C.B., Behrenfeld, M.J., Randerson, J.T., Falkowski, P. (1998). Primary production of the biosphere: integrating terrestrial and oceanic components. Science, 281, 237–240. doi:10.1126/science.281.5374.237

   Type: independent peer-reviewed paper. Checked against: Abstract.

4. Elbert, W., Weber, B., Burrows, S., Steinkamp, J., et al. (2012). Contribution of cryptogamic covers to the global cycles of carbon and nitrogen. Nature Geoscience, 5, 459–462. doi:10.1038/ngeo1486

   Type: independent peer-reviewed paper. Checked against: Abstract and Supplementary Information.

5. Davies-Barnard, T., Friedlingstein, P. (2020). The global distribution of biological nitrogen fixation in terrestrial natural ecosystems. Global Biogeochemical Cycles, 34, e2019GB006387. doi:10.1029/2019GB006387

   Type: independent peer-reviewed paper. Checked against: Abstract.

6. Drake, T.W., Raymond, P.A., Spencer, R.G.M. (2018). Terrestrial carbon inputs to inland waters: a current synthesis of estimates and uncertainty. Limnology and Oceanography Letters, 3, 132–142. doi:10.1002/lol2.10055

   Type: independent peer-reviewed paper. Checked against: Abstract.

7. Tian, H., Yao, Y., Li, Y., Shi, H., et al. (2023). Increased terrestrial carbon export and CO₂ evasion from global inland waters since the preindustrial era. Global Biogeochemical Cycles, 37, e2023GB007776. doi:10.1029/2023GB007776

   Type: independent peer-reviewed paper. Checked against: Abstract.

8. Raymond, P.A., Hartmann, J., Lauerwald, R., Sobek, S., et al. (2013). Global carbon dioxide emissions from inland waters. Nature, 503, 355–359. doi:10.1038/nature12760

   Type: independent peer-reviewed paper. Checked against: Abstract.

9. Mendonça, R., Müller, R.A., Clow, D., Verpoorter, C., et al. (2017). Organic carbon burial in global lakes and reservoirs. Nature Communications, 8, 1694. doi:10.1038/s41467-017-01789-6

   Type: independent peer-reviewed paper. Checked against: Abstract.

10. Regnier, P., Resplandy, L., Najjar, R.G., Ciais, P. (2022). The land-to-ocean loops of the global carbon cycle. Nature, 603, 401–410. doi:10.1038/s41586-021-04339-9

    Type: independent peer-reviewed paper. Checked against: Abstract.

11. Resplandy, L., Keeling, R.F., Rödenbeck, C., Stephens, B.B., et al. (2018). Revision of global carbon fluxes based on a reassessment of oceanic and riverine carbon transport. Nature Geoscience, 11, 504–509. doi:10.1038/s41561-018-0151-3

    Type: independent peer-reviewed paper. Checked against: Abstract.

12. Tubiello, F.N., Biancalani, R., Salvatore, M., Rossi, S., Conchedda, G. (2016). A worldwide assessment of greenhouse gas emissions from drained organic soils. Sustainability, 8, 371. doi:10.3390/su8040371

    Type: independent peer-reviewed paper. Checked against: Abstract.

13. Leifeld, J., Menichetti, L. (2018). The underappreciated potential of peatlands in global climate change mitigation strategies. Nature Communications, 9, 1071. doi:10.1038/s41467-018-03406-6

    Type: independent peer-reviewed paper. Checked against: Abstract.

14. Yu, Z., Loisel, J., Brosseau, D.P., Beilman, D.W., Hunt, S.J. (2010). Global peatland dynamics since the Last Glacial Maximum. Geophysical Research Letters, 37. doi:10.1029/2010GL043584

    Type: independent peer-reviewed paper. Checked against: Abstract.

15. Jobbágy, E.G., Jackson, R.B. (2000). The vertical distribution of soil organic carbon and its relation to climate and vegetation. Ecological Applications, 10, 423–436. doi:10.1890/1051-0761(2000)010[0423:TVDOSO]2.0.CO;2

    Type: independent peer-reviewed paper. Checked against: Abstract.

Further reading

• The Global Carbon Project publishes the annual Global Carbon Budget, with data and figures: globalcarbonbudget.org.
• The IPCC Sixth Assessment Report, Working Group I, Chapter 5, is freely available at ipcc.ch/report/ar6/wg1.

Spotted an error or a newer estimate? Please let us know.