Global Carbon Budget 2021

4 November 2021

Nearly 100 researchers from 70 institutions across 18 nations have – for the 10th consecutive year – synthesized global and regional measurements, national statistics, and model outcomes to submit an updated Global Carbon Budget to the Earth System Science Data journal:

Working on historical (since 1750), recent (since 1960), and immediate past (2011 to 2020) time scales, including projections for 2021, their work provides transparent, traceable, publicly-accessible assessment of the status of our planet. Their analysis shows that ocean and land carbon sinks have increased roughly proportional to CO2 emissions. Atmospheric CO2 concentrations also continue to increase, despite COVID-related reductions in 2020, due to continued CO2 emissions. They estimate that global fossil fuel emissions in 2021 will return toward 2019 levels. They do not find a trend (since 1960) in their carbon budget imbalance, suggesting that current accounting of the planetary carbon cycle includes most of the important features; future improvements will require better understanding of land (especially Northern Hemisphere) and ocean (especially Southern Ocean) carbon processing. They offer careful detailed description of all sources, assumptions, quality control, and uncertainty analysis in their most recent submission and ensure free fully-open access to synthesized and country-specific data via While a global community of scientists discusses and evaluates this latest submission, policy makers, businesses, journalists, and non-governmental organizations can check and benefit from their assessments of permissible remaining carbon emissions to meet various global atmospheric temperature targets.

The annual update of the global carbon budget is produced by the Global Carbon Project and was started in 2006. This is the 10th update of the global carbon budget published by ESSD in the living data format:

Global Carbon Budget 2021
Friedlingstein, P., Jones, M. W., O'Sullivan, M., Andrew, R. M., Bakker, D. C. E., Hauck, J., Le Quéré, C., Peters, G. P., Peters, W., Pongratz, J., Sitch, S., Canadell, J. G., Ciais, P., Jackson, R. B., Alin, S. R., Anthoni, P., Bates, N. R., Becker, M., Bellouin, N., Bopp, L., Chau, T. T. T., Chevallier, F., Chini, L. P., Cronin, M., Currie, K. I., Decharme, B., Djeutchouang, L., Dou, X., Evans, W., Feely, R. A., Feng, L., Gasser, T., Gilfillan, D., Gkritzalis, T., Grassi, G., Gregor, L., Gruber, N., Gürses, Ö., Harris, I., Houghton, R. A., Hurtt, G. C., Iida, Y., Ilyina, T., Luijkx, I. T., Jain, A. K., Jones, S. D., Kato, E., Kennedy, D., Klein Goldewijk, K., Knauer, J., Korsbakken, J. I., Körtzinger, A., Landschützer, P., Lauvset, S. K., Lefèvre, N., Lienert, S., Liu, J., Marland, G., McGuire, P. C., Melton, J. R., Munro, D. R., Nabel, J. E. M. S., Nakaoka, S.-I., Niwa, Y., Ono, T., Pierrot, D., Poulter, B., Rehder, G., Resplandy, L., Robertson, E., Rödenbeck, C., Rosan, T. M., Schwinger, J., Schwingshackl, C., Séférian, R., Sutton, A. J., Sweeney, C., Tanhua, T., Tans, P. P., Tian, H., Tilbrook, B., Tubiello, F., van der Werf, G., Vuichard, N., Wada, C., Wanninkhof, R., Watson, A., Willis, D., Wiltshire, A. J., Yuan, W., Yue, C., Yue, X., Zaehle, S., and Zeng, J.
Earth Syst. Sci. Data Discuss. [preprint],, in review, 2021.

Contact: Pierre Friedlingstein (