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4036 Yang, X., Thornton, P., Ricciuto, D., Wang, Y., and Hoffman, F.: Global evaluation of terrestrial biogeochemistry in the Energy Exascale Earth System Model (E3SM) and the role of the phosphorus cycle in the historical terrestrial carbon balance, Biogeosciences, 20, 2813–2836, https://doi.org/10.5194/bg-20-2813-2023, 2023.

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4043 Yao, Y., Ciais, P., Viovy, N., Joetzjer, E. and Chave, J.: How drought events during the last century have impacted biomass carbon in Amazonian rainforests. Global Change Biology, 29(3), pp.747-762, https://doi.org/10.1111/gcb.16504, 2023.

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<figure><img src="image_107.png" /></figure>

4094 Tables

4095

4096 Table 1. Factors used to convert carbon in various units (by convention, Unit 1 = Unit 2 × conversion).

<table><thead><tr><td>Unit 1</td><td>Unit 2</td><td>Conversion</td><td>Source</td></tr></thead><tbody><tr><td>GtC (gigatonnes of carbon)</td><td>ppm (parts per million) (a)</td><td>2.124 (b)</td><td>Ballantyne et al. (2012)</td></tr><tr><td>GtC (gigatonnes of carbon)</td><td>PgC (petagrams of carbon)</td><td>1</td><td>SI unit conversion</td></tr><tr><td>GtCO2 (gigatonnes of carbon dioxide)</td><td>GtC (gigatonnes of carbon)</td><td>3.664</td><td>44.01/12.011 in mass equivalent</td></tr></tbody></table>

(a) Measurements of atmospheric CO₂ concentration have units of dry-air mole fraction. ‘ppm’ is an abbreviation for micromole/mol, dry air.

(b) The use of a factor of 2.124 assumes that all the atmosphere is well mixed within one year. In reality, only the troposphere is well mixed and the growth rate of CO₂ concentration in the less well-mixed stratosphere is not measured by sites from the NOAA network. Using a factor of 2.124 makes the approximation that the growth rate of CO₂ concentration in the stratosphere equals that of the troposphere on a yearly basis.

4097
<figure><img src="image_108.png" /><figcaption>4098 **Table 2.** How to cite the individual components of the global carbon budget presented here.</figcaption></figure>

<table><thead><tr><td>Component</td><td>Primary reference</td></tr></thead><tbody><tr><td>Global fossil CO<sub>2</sub> emissions (EFOS), total and by fuel type</td><td>Andrew and Peters (2025)</td></tr><tr><td>National territorial fossil CO<sub>2</sub> emissions (EFOS)</td><td>Erb and Marland (2025), UNFCCC (2022)</td></tr><tr><td>National consumption-based fossil CO<sub>2</sub> emissions (EFOS) by country (consumption)</td><td>Peters et al. (2011a) updated as described in this paper</td></tr><tr><td>Net land-use change flux (ELUC)</td><td>This paper (see Table 4 for individual model references).</td></tr><tr><td>Growth rate in atmospheric CO<sub>2</sub> concentration (GATM)</td><td>Lan et al. (2025a)</td></tr><tr><td>Ocean and land CO<sub>2</sub> sinks (SOCEAN and SLAND)</td><td>This paper (see Table 4 for individual model and data products references).</td></tr></tbody></table>

4099
<figure><img src="image_109.png" /></figure>

Table 3. Main methodological changes in the global carbon budget this year (GCB2025). Empty cells mean there were no methodological changes introduced that year. Table S9 lists methodological changes from the first global carbon budget publication up to 2024.

<table><thead><tr><th colspan="2">Fossil fuel emissions</th><th rowspan="2">LUC emissions</th><th colspan="3">Reservoirs</th><th rowspan="2">Other changes</th></tr><tr><th>Global</th><th>Country (territorial)</th><th>Atmosphere</th><th>Ocean</th><th>Land</th></tr></thead><tbody><tr><td></td><td></td><td>Bookkeeping estimates derived from models that estimate ELUC based on transient carbon densities responding to environmental changes (BLUE, OSCAR, LUCE).</td><td>Include an assessment of satellite-derived growth rates</td><td>Adjustments applied for known underestimation of GOBMs and cool surface skin effect in fCO2-products. Suspension of 19 ocean data sets from SOCAT.</td><td>Include the RSS adjustment.</td><td></td></tr></tbody></table>

4103
<figure><img src="image_110.png" /></figure>

4104 Table 4. References for the process models, bookkeeping models, ocean data products, and atmospheric

4105 inversions. All models and products are updated with new data to the end of year 2024.

4106

<table><thead><tr><th>Model/data name</th><th>Reference</th><th>Change from Global Carbon Budget 2024 (Friedlingstein et al., 2025a)</th></tr></thead><tbody><tr><td colspan="3"><strong>Bookkeeping models for land-use change emissions</strong></td></tr><tr><td>BLUE</td><td>Hansis et al. (2015)</td><td>Transient C densities used to estimate ELUC</td></tr><tr><td>OSCAR</td><td>Gasser et al. (2020)</td><td>No change</td></tr><tr><td>LUCE</td><td>Qin et al. (2024)</td><td>Transient C densities used to estimate ELUC</td></tr><tr><td colspan="3"><strong>Dynamic global vegetation models</strong></td></tr><tr><td>CABLE-POP</td><td>Haverd et al. (2018)</td><td>corrected N deposition input data, minor parameter changes</td></tr><tr><td>CLASSIC</td><td>Melton et al. (2020), Gauthier et al. (2025), Kou-Giesbrecht and Arora (2022)</td><td></td></tr><tr><td>CLM6.0</td><td>Lawrence et al. (2019)</td><td>New dust scheme, new BGC fire method, updates to MEGAN for BVOCs, parameter updates, new surface datasets, new N fixation method</td></tr><tr><td>CLM-FATES</td><td>Fisher et al. (2015), Koven et al. (2020)</td><td>New model</td></tr><tr><td>DLEM</td><td>Tian et al. (2015), You et al. (2022)</td><td>No change</td></tr><tr><td>EDv3</td><td>Moorcroft et al. (2001), Ma et al. (2022)</td><td>Updated meteorology inputs (i.e. hourly air temperature)</td></tr><tr><td>ELM</td><td>Yang et al. (2023), Burrows et al. (2020)</td><td>No change</td></tr><tr><td>ELM-FATES</td><td>Fisher et al. (2015), Koven et al. (2020), Needham et al. (2025)</td><td>New model</td></tr><tr><td>GDSTEM</td><td>Felzer et al. (2009), Felzer et al. (2011), Felzer (2012), Felzer and Jiang (2018)</td><td>New model</td></tr><tr><td>IBIS</td><td>Xia et al., (2024)</td><td>No change</td></tr><tr><td>iMAPLE</td><td>Yue et al. (2024)</td><td>No change.</td></tr></tbody></table>
<figure><img src="image_111.png" /></figure>

<table><tbody><tr><td>ISAM</td><td>Jain et al. (2013), Meiyappan et al. (2015), Shu et al. (2020)</td><td>Vertically resolved soil biogeochemistry (carbon and nitrogen) module, following Shu et al. (2020)</td></tr><tr><td>JSBACH</td><td>Mauritsen et al. (2019), Reick et al. (2021)</td><td>No change</td></tr><tr><td>JULES-ES</td><td>Wiltshire et al. (2021), Sellar et al. (2019), Burton et al. (2019)</td><td>Minor updates to wildfire parameters</td></tr><tr><td>LPJ-GUESS</td><td>Smith et al. (2014)</td><td>Wood harvest without the LUH2 secondary mature, young, and non-forest harvest fraction info</td></tr><tr><td>LPJmL</td><td>Schaphoff et al. (2018), von Bloh et al. (2018), Lutz et al., (2019), Heinke et al. (2023)</td><td>Switch from version 5.7.5 to 5.10.0 incorporating updates to soil temperature scheme, revised N demand and N uptake processes, revised tree phenology, as well as bugfixes and code improvements</td></tr><tr><td>LPJ-EOSIM</td><td>Poulter et al. (2011) (d)</td><td>Incorporation of new respiration temperature responses and leaf respiration acclimation, updated the soil temperature and water scheme to have 8 layers</td></tr><tr><td>LPX-Bern</td><td>Lienert and Joos (2018)</td><td>No change</td></tr><tr><td>ORCHIDEEv3</td><td>Krinner et al. (2005), Zaehle and Friend (2010), Vuichard et al. (2019)</td><td>No change</td></tr><tr><td>SDGVM</td><td>Woodward and Lomas (2004), Walker et al. (2017)</td><td>Reverted to version used in Friedlingstein et al. (2022), but retaining the recent bug fix to monthly heterotrophic respiration output</td></tr><tr><td>VISIT</td><td>Ito and Inatomi (2012), Kato et al. (2013)</td><td>No change</td></tr><tr><td>VISIT-UT</td><td>Ito (2019)</td><td>New model</td></tr><tr><td colspan="3"><strong>Intermediate complexity land carbon cycle model</strong></td></tr><tr><td>CARDAMOM</td><td>Bloom et al. (2016), Smallman et al. (2021)</td><td>Analysis resolution increased from 1 x1 to 0.5x0.5 degree. Estimates of fAPAR from MODIS collection 6.1. New prior constraint on the leaf carbon per unit area parameter (LCA). MODIS burned area forcing was replaced by GFEDv5 burned area estimate</td></tr><tr><td colspan="3"><strong>Global ocean biogeochemistry models</strong></td></tr><tr><td>NEMO-PlankTOM12</td><td>Wright et al. (2021)</td><td>No change</td></tr><tr><td>NEMO4.2-PISCES (IPSL)</td><td>Aumont et al. (2015)</td><td>No change to the model version, but switch to ERA5 forcing - A,B,C,D simulations have been re-run starting from GCB2024 simulation restart fields from 1940 onwards</td></tr><tr><td>MICOM-HAMOCC (NorESM1-OCv1.2)</td><td>Schwinger et al. (2016)</td><td>No change, model has been re-run to provide monthly CFC/SF<sub>6</sub> outputs</td></tr><tr><td>MPIOM-</td><td>Lacroix et al. (2021)</td><td>No change</td></tr></tbody></table>
<figure><img src="image_112.png" /></figure>

<table><tbody><tr><td>HAMOCC6</td><td></td><td></td></tr><tr><td>NEMO3.6-PISCESv2-gas (CNRM)</td><td>Berthet et al. (2019), Séférian et al. (2019)</td><td>Updated simulations using 1750 preindustrial conditions instead of 1850. No change in model configuration, except nudging of surface ocean fields applied to minimize the change of atm forcing. The methodology used is based on Sanchez-Gomez et al. (2024)</td></tr><tr><td>FESOM2.1-REcoM3</td><td>Gürses et al. (2023)</td><td>Switched to ERA5 forcing - A,B,C,D simulations have been re-run starting from GCB2024 simulation restart fields</td></tr><tr><td>MOM6-COBALTv3 (Princeton)</td><td>Stock et al., (2025)</td><td>New model configuration MOM6-COBALTv3 with ~1° horizontal resolution (360x210). 1) updated ocean biogeochemical module COBALTv3 with an additional fixed nitrogen removal process - anaerobic ammonium oxidation (anammox); 2) updated air-sea gas exchange scheme - wind-wave-bubble formulation; 3) updated riverine carbon and nutrient inputs following R2OMIP protocol (Lacroix et al., 2024, https://zenodo.org/records/13799103); 4) updated river water discharge files.</td></tr><tr><td>CESM-ETHZ</td><td>Doney et al. (2009)</td><td>Compared to the 2024 submission, we changed the forcing to ERA5. To this end, a new spinup was performed, extending over 500 years.</td></tr><tr><td>MRI-ESM2-4</td><td>Tsujino et al. (2024), Sakamoto et al. (2023)</td><td>Iron circulation is modified according to Moore and Braucher (2008) and iron limitation on primary production is adjusted according to this change. Updated atmospheric CO2 for simulations A and C. The JRA-3Q reanalysis (Kosaka et al. 2024) is used to physically force the model. The model is spun up for 1925 years with xCO2=278ppm.</td></tr><tr><td>ACCESS (CSIRO)</td><td>Law et al. (2017)</td><td>No change in model since GCB2024, but switched to ERA5 forcing and extended spinup.</td></tr><tr><td colspan="3"><strong>fcO2-products</strong></td></tr><tr><td>VLIZ-SOMFFN</td><td>Landschützer et al. (2016)</td><td>Time period extended to 2024</td></tr><tr><td>Jena-MLS</td><td>Rödenbeck et al. (2014) updated to Rödenbeck et al (2022)</td><td>Time period extended to 2024</td></tr><tr><td>CMEMS-LSCE-FFNNv2</td><td>Chau et al. (2022)</td><td>Time period extended to 2024</td></tr><tr><td>UEXP-FNN-U</td><td>Watson et al. (2020) and Ford et al. (2024)</td><td>Updated to recalculated SOCATv2025 dataset (Ford et al. 2025). Updated salinity dataset to use a tiered approach (described in Gregor et al. 2024) including ESA CCI-SSS (v5.51) and CMEMS GLORYS12V1. Updated time period to 1980 to 2024</td></tr><tr><td>NIES-ML3</td><td>Zeng et al. (2022)</td><td>Time period extended to 2024.</td></tr><tr><td>JMA-MLR</td><td>liida et al. (2021)</td><td>Time period extended to 2024. Updated to recalculated SOCATv2025 dataset (Ford et al. 2025)</td></tr><tr><td>OceanSODA-ETHZv2</td><td>Gregor et al. (2024)</td><td>Time period extended to 2024</td></tr></tbody></table>
<figure><img src="image_113.png" /></figure>

<table><tbody><tr><td>LDEO-HPD</td><td>Gloege et al. (2022) and Bennington et al. (2022)</td><td>Time period extended to 2024</td></tr><tr><td>CSIR-ML6</td><td>Gregor et al. (2019)</td><td>Time period extended to 2024</td></tr><tr><td colspan="3"><strong>Atmospheric inversions</strong></td></tr><tr><td>Jena<br>CarboScope</td><td>Rödenbeck et al. (2018) & Stephens et al. (2007).</td><td>Slight change in station set. Numerical flux resolution 2x2. TM3 run on spatial resolution 6x4 (multiple of 2x2)</td></tr><tr><td>CarbonTracker<br>Europe (CTE)</td><td>van der Laan-Luijkx et al. (2017)</td><td>Update of prior fluxes and assimilated observations.</td></tr><tr><td>NISMON-CO2</td><td>Niwa et al. (2022), Niwa et al. (2017).</td><td>Update of prior fluxes, specifically changed GFED to GBEI. Update of the meteorological input to JRA-3Q. Including more CO2 observations.</td></tr><tr><td>CT-NOAA</td><td>Jacobson et al. (2025), Byrne et al. (2023), Krol et al. (2005), Peiro et al. (2022)</td><td>New air-sea gas exchange and new terrestrial NBE (Jacobson et al., 2025). Unlike previous submissions, CT2025 uses only one set of priors.</td></tr><tr><td>CMS-Flux</td><td>Liu et al. (2021)</td><td>Update of prior fluxes and assimilated observations.</td></tr><tr><td>CAMS-Satellite</td><td>Chevallier et al. (2005) and Chevallier et al. (2025)</td><td>Update of the prior fluxes and assimilated observations.</td></tr><tr><td>GONGGA</td><td>Jin et al. (2024)</td><td>Update of the prior fluxes and assimilated observations.</td></tr><tr><td>COLA</td><td>Liu et al. (2022)</td><td>Update of the prior fluxes and assimilated observations.</td></tr><tr><td>GCASv2</td><td>Jiang et al. (2021) & Emmons et al. (2010)</td><td>Update of the prior fluxes and assimilated observations.</td></tr><tr><td>UoE</td><td>Feng et al. (2016) & Palmer et al. (2019)</td><td>Update of the prior fluxes and assimilated observations.</td></tr><tr><td>MIROC-ACTM</td><td>Chandra et al. (2022) & Patra et al. (2018)</td><td>Update of assimilated observations and prior fluxes, specifically changed to MiCASA and GFED. Update of the meteorological input to JRA-3Q.</td></tr><tr><td>NTFVAR</td><td>Nayagam et al. (2025) & Maksyutov et al. (2021)</td><td>Update of prior fluxes and assimilated observations.</td></tr><tr><td>THU</td><td>Kong et al. (2022)</td><td>New this year, after missing out 1 year. Compared to the previous submission: update of prior fluxes and assimilated observations.</td></tr><tr><td>NISMON-CO2_GOSAT</td><td>Niwa et al. (2022), Niwa et al. (2017).</td><td>New this year.</td></tr><tr><td colspan="3"><strong>Earth System Models</strong></td></tr><tr><td>CanESM5</td><td>Swart et al. (2019), Sospedra-Alfonso et al. (2021)</td><td>No change</td></tr><tr><td>EC-Earth3-CC</td><td>Döscher et al. (2021), Bilbao et al. (2021), Bernardello et al. (2024)</td><td>No change</td></tr><tr><td>IPSL-CM6A-CO2-LR</td><td>Boucher et al. (2020)</td><td>No change</td></tr><tr><td>MIROC-ES2L</td><td>Watanabe et al. (2020)</td><td>No change</td></tr></tbody></table>
<figure><img src="image_114.png" /></figure>

<table><tr><td>MPI-ESM1-2-LR</td><td>Mauritsen et al. (2019), Li et al. (2023)</td><td>No change</td></tr><tr><td>NorCPM-CC</td><td>Tjiputra et al. (2020), Bethke et al. (2021)</td><td>New this year.</td></tr></table>

4107
<figure><img src="image_115.png" /></figure>

**Table 5.** Comparison of results from the bookkeeping method and budget residuals with results from the
DGVMs, as well as additional estimates from atmospheric oxygen, atmospheric inversions and Earth System
Models (ESMs) for different periods, the last decade, and the last year available. All values are in GtC yr⁻¹. The
best estimate for GCB2025 (E_LUC) is calculated with the bookkeeping models (1a) and used in the budget Table
7, see Section 2 and Figure 7 for description of the bookkeeping component fluxes. The best estimate for
GCB2025 (S_LAND) is calculated with the DGVMs including the RSS correction (2b), and used in the budget
Table 7. The DGVM uncertainties represent ±1σ of the decadal or annual (for 2024) estimates from the
individual DGVMs. For the inverse systems the mean and range of available results is given when the number
of systems is less than 10, otherwise the ±1σ is provided. All values are rounded to the nearest 0.1 GtC and
therefore columns do not necessarily add to zero.

4118 Mean (GtC yr⁻¹)

<table><thead><tr><th></th><th>1960s</th><th>1970s</th><th>1980s</th><th>1990s</th><th>2000s</th><th>2010s</th><th>2015-2024</th><th>2024</th></tr></thead><tbody><tr><td>Bookkeeping (BK) Net flux (1a)</td><td>1.9±0.7</td><td>1.7±0.7</td><td>1.7±0.7</td><td>1.7±0.7</td><td>1.7±0.7</td><td>1.6±0.7</td><td>1.4±0.7</td><td>1.3±0.7</td></tr><tr><td>BK - deforestation (total)</td><td>1.8[1.6,2.1]</td><td>1.8[1.6,2.1]</td><td>1.7[1.5,1.9]</td><td>1.9[1.6,2.1]</td><td>2[1.7,2.2]</td><td>2[1.6,2.4]</td><td>1.9[1.5,2.3]</td><td>1.9[1.4,2.4]</td></tr><tr><td>BK - forest regrowth (total)</td><td>-0.9[-1,-0.7]</td><td>-0.9[-1,-0.8]</td><td>-0.9[-1,-0.8]</td><td>-1[-1,1,-0.8]</td><td>-1.1[-1,1,-0.9]</td><td>-1.3[-1,1,-0.9]</td><td>-1.3[-1,1,-1]</td><td>-1.3[-1,1,-1]</td></tr><tr><td>Land-use change emissions (E<sub>LUC</sub>)</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>BK - other transitions</td><td>0.3[0.3,0.3]</td><td>0.2[0.2,0.3]</td><td>0.2[0.1,0.3]</td><td>0.1[0.1,0.2]</td><td>0.1[0,0.1]</td><td>0.2[0.1,0.2]</td><td>0.1[0.1,0.1]</td><td>0.1[0.1,0.1]</td></tr><tr><td>BK - peat drainage & peat fires</td><td>0.2[0.1,0.2]</td><td>0.2[0.1,0.2]</td><td>0.2[0.2,0.2]</td><td>0.3[0.2,0.3]</td><td>0.2[0.2,0.3]</td><td>0.3[0.3,0.3]</td><td>0.2[0.2,0.3]</td><td>0.2[0.2,0.2]</td></tr><tr><td>BK - wood harvest & forest management</td><td>0.4[0.1,0.6]</td><td>0.4[0.1,0.6]</td><td>0.5[0.1,0.7]</td><td>0.5[0.1,0.7]</td><td>0.5[0.1,0.7]</td><td>0.4[0.1,0.7]</td><td>0.4[0.1,0.7]</td><td>0.4[0.1,0.7]</td></tr><tr><td>DGVMs-net flux (1b)</td><td>1.3±0.5</td><td>1.2±0.5</td><td>1.2±0.5</td><td>1.2±0.5</td><td>1.2±0.6</td><td>1.1±0.6</td><td>1±0.6</td><td>0.9±0.5</td></tr><tr><td>Terrestrial sink (S<sub>LAND</sub>)</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Residual sink from global budget (E<sub>FOS</sub>+E<sub>LUC</sub>(1a)-G<sub>ATM</sub>-S<sub>OCEAN</sub>) (2a)</td><td>1.9±0.8</td><td>2±0.8</td><td>1.7±0.9</td><td>2.6±0.9</td><td>2.9±0.9</td><td>3±0.9</td><td>2.4±0.9</td><td>0.3±1</td></tr><tr><td>DGVMs (2b)</td><td>0.9±0.3</td><td>1.6±0.5</td><td>1.4±0.6</td><td>2±0.5</td><td>2.2±0.6</td><td>2.5±0.7</td><td>2.4±0.8</td><td>1.9±0.9</td></tr><tr><td>Net land fluxes (S<sub>LAND</sub>-E<sub>LUC</sub>)</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>GCB2025 Budget (2b-1a)</td><td>-0.9±0.8</td><td>0.1±0.9</td><td>0.3±0.9</td><td>0.2±0.9</td><td>0.5±0.9</td><td>0.9±1</td><td>1±1</td><td>0.7±1.1</td></tr><tr><td>Atmospheric O<sub>2</sub></td><td>---</td><td>---</td><td>---</td><td>1.3±0.6</td><td>0.9±0.7</td><td>1±0.8</td><td>0.7±0.8</td><td>-</td></tr></tbody></table>
<figure><img src="image_116.png" /></figure>

<table><thead><tr><th></th><th>1960s</th><th>1970s</th><th>1980s</th><th>1990s</th><th>2000s</th><th>2010s</th><th>2015-2024</th><th>2024</th></tr></thead><tbody><tr><td>DGVMs-net (2b-1b)</td><td>-0.3±0.4</td><td>0.4±0.6</td><td>0.2±0.5</td><td>0.8±0.4</td><td>1±0.4</td><td>1.4±0.6</td><td>1.4±0.7</td><td>1.1±0.8</td></tr><tr><td>Inversions*</td><td>-[-,-]</td><td>-[-,-]</td><td>-[-,-]</td><td>0.7[0.6,0.8]<br>(2)</td><td>1.4[1.3,1.6]<br>(3)</td><td>1.5[1.3,2.3]<br>(8)</td><td>1.3±0.3<br>(14)</td><td>0.2±0.7<br>(14)</td></tr><tr><td>ESMs</td><td>0[-0.7,0.5]</td><td>1.5[1.2,2.1]</td><td>1.1[0.5,1.4]</td><td>1.8[1.2,2.4]</td><td>1.8[0.4,2.7]</td><td>2[0.7,3.1]</td><td>2.3[-0.1,3.6]</td><td>0.8[-2.9-3.3]</td></tr></tbody></table>

<footnote>*Estimates are adjusted for the pre-industrial influence of river fluxes, for the cement carbonation sink, and adjusted to common EFOS (Sect. 2.7). The ranges given include varying numbers (in parentheses) of inversions in each decade (Table A4)</footnote>
<figure><img src="image_117.png" /></figure>

**Table 6:** Comparison of results for the un-adjusted ocean sinks from the f/CO₂-products, from global ocean biogeochemistry models (GOBMs), the best estimate for GCB2025 (adjusted SOCEAN) calculated from f/CO₂-products and GOBMs) and used in the budget Table 7, as well as additional estimates from ocean interior observation-based changes in the dissolved inorganic carbon (DIC) inventory, atmospheric oxygen, atmospheric inversions and Earth System Models (ESMs) for different periods, the last decade, and the last year available. All values are in GtC yr⁻¹. Uncertainties represent ±1σ of the estimates from the GOBMs and inversions (n>10) and range of ensemble members is given for ensembles with n<10 (f/CO₂-products, inversions, ocean interior, ESMs). The uncertainty of the GCB2025 budget estimate is based on expert judgement (Section 2 and Supplement S1 to S4) and for oxygen it is the standard deviation of a Monte Carlo ensemble (Section 2.8). Note that adjustments were applied to the f/CO₂-products and two of the ocean interior estimates to match the definition of SOCEAN (see section 2.5.1 and S3.6).

<table><caption>Mean (GtC yr<sup>-1</sup>)</caption><thead><tr><th>Product</th><th>1960s</th><th>1970s</th><th>1980s</th><th>1990s</th><th>2000s</th><th>2010s</th><th>2015-2024</th><th>2024</th></tr></thead><tbody><tr><td>GCB2025 Budget</td><td>1.3±0.4</td><td>1.6±0.4</td><td>2.1±0.4</td><td>2.3±0.4</td><td>2.6±0.4</td><td>3.1±0.4</td><td>3.2±0.4</td><td>3.4±0.4</td></tr><tr><td>fCO<sub>2</sub>-products</td><td>---</td><td>---</td><td>---</td><td>2.3 [2,3]</td><td>2.5 [2.4,2.9]</td><td>3.1 [2.9,3.5]</td><td>3.3 [2.9,3.9]</td><td>3.5 [2.8,4.2]</td></tr><tr><td>GOBMs</td><td>1.1±0.2</td><td>1.3±0.3</td><td>1.8±0.3</td><td>2.0±0.3</td><td>2.2±0.3</td><td>2.6±0.3</td><td>2.7±0.3</td><td>2.9±0.3</td></tr><tr><td>Atmospheric O<sub>2</sub></td><td>---</td><td>---</td><td>---</td><td>2.0±0.4</td><td>2.8±0.4</td><td>3.4±0.5</td><td>3.5±0.5</td><td>-</td></tr><tr><td>Inversions</td><td>- [-,-]</td><td>- [-,-]</td><td>- [-,-]</td><td>2.4 [2.2,2.5] (2)</td><td>2.3 [2.2,2.4] (3)</td><td>2.9 [2.1,3.1] (8)</td><td>3±0.3 (14)</td><td>3±0.4 (14)</td></tr><tr><td>Ocean interior</td><td>1.1 [-,-]</td><td>1.3 [-,-]</td><td>1.8 [-,-]</td><td>2.1 [2,2.3]</td><td>2.2 [1.7,2.5]</td><td>3.3 [2.7,4]</td><td>---</td><td>-</td></tr><tr><td>ESMs</td><td>0.7 [0.1,1.1]</td><td>1 [0.4,1.4]</td><td>1.5 [0.7,2]</td><td>1.7 [1.1,2.1]</td><td>1.9 [1.5,2.2]</td><td>2.4 [2.2,7]</td><td>2.5 [2.2,2.8]</td><td>2.6 [2.2-3.1]</td></tr></tbody></table>

4133

4134

4135
<figure><img src="image_118.png" /></figure>

**Table 7:** Decadal mean in the five components of the anthropogenic CO₂ budget for different periods, and last year available. All values are in GtC yr⁻¹, and uncertainties are reported as ±1σ. Fossil CO₂ emissions include cement carbonation. The table also shows the budget imbalance (BIM), which provides a measure of the discrepancies among the nearly independent estimates. A positive imbalance means the emissions are overestimated and/or the sinks are too small. All values are rounded to the nearest 0.1 GtC and therefore columns do not necessarily add to zero.

4146 Mean (GtC yr⁻¹)

<table><thead><tr><th></th><th></th><th>1960s</th><th>1970s</th><th>1980s</th><th>1990s</th><th>2000s</th><th>2010s</th><th>2015-2024</th><th>2024</th><th>2025 (Projection)</th></tr></thead><tbody><tr><td rowspan="3">Total emissions (E<sub>FOS</sub> + E<sub>LUC</sub>)</td><td>Fossil CO2 emissions (E<sub>FOS</sub>)*</td><td>3±0.2</td><td>4.7±0.2</td><td>5.4±0.3</td><td>6.4±0.3</td><td>7.8±0.4</td><td>9.5±0.5</td><td>9.8±0.5</td><td>10.3±0.5</td><td>10.4±0.5</td></tr><tr><td>Land-use change emissions (E<sub>LUC</sub>)</td><td>1.9±0.7</td><td>1.7±0.7</td><td>1.7±0.7</td><td>1.7±0.7</td><td>1.7±0.7</td><td>1.6±0.7</td><td>1.4±0.7</td><td>1.3±0.7</td><td>1.1±0.7</td></tr><tr><td>Total emissions</td><td>4.9±0.7</td><td>6.4±0.7</td><td>7.1±0.8</td><td>8.1±0.8</td><td>9.5±0.8</td><td>11.1±0.8</td><td>11.2±0.9</td><td>11.6±0.9</td><td>11.5±0.9</td></tr><tr><td rowspan="3">Partitoning</td><td>Growth rate in atmos CO2 (G<sub>ATM</sub>)</td><td>1.7±0.07</td><td>2.8±0.07</td><td>3.4±0.02</td><td>3.1±0.02</td><td>4±0.02</td><td>5.1±0.02</td><td>5.6±0.02</td><td>7.9±0.2</td><td>4.9±0.2</td></tr><tr><td>Ocean sink (S<sub>OCEA</sub>)</td><td>1.3±0.4</td><td>1.6±0.4</td><td>2.1±0.4</td><td>2.3±0.4</td><td>2.6±0.4</td><td>3.1±0.4</td><td>3.2±0.4</td><td>3.4±0.4</td><td>3.2±0.4</td></tr><tr><td>Terrestrial sink (S<sub>LAND</sub>)</td><td>0.9±0.3</td><td>1.6±0.5</td><td>1.4±0.6</td><td>2±0.5</td><td>2.2±0.6</td><td>2.5±0.7</td><td>2.4±0.8</td><td>1.9±0.9</td><td>3.4±1</td></tr><tr><td>Budge Imbalance</td><td>BIM= E<sub>FOS</sub>+ E<sub>LUC</sub> (G<sub>ATM</sub> +S<sub>OCEA</sub>)</td><td>0.9</td><td>0.5</td><td>0.3</td><td>0.7</td><td>0.7</td><td>0.4</td><td>0</td><td>-1.7</td><td></td></tr></tbody></table>
<figure><img src="image_119.png" /></figure>

<table><thead><tr><th></th><th>1960s</th><th>1970s</th><th>1980s</th><th>1990s</th><th>2000s</th><th>2010s</th><th>2015-2024</th><th>2024</th><th>2025 (Projection)</th></tr></thead><tbody><tr><td>N+S<sub>LAN</sub><br>D)</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>

<footnote>*Fossil emissions excluding the cement carbonation sink amount to 3±0.2 GtC yr⁻¹, 4.7±0.2 GtC yr⁻¹, 5.5±0.3 GtC yr⁻¹, 6.4±0.3 GtC yr⁻¹, 7.9±0.4 GtC yr⁻¹, and 9.7±0.5 GtC yr⁻¹ for the decades 1960s to 2010s respectively and to 10±0.5 GtC yr⁻¹ for 2024, and 10.5±0.5 GtC yr⁻¹ for 2025.</footnote>
<figure><img src="image_120.png" /></figure>

**Table 8.** Cumulative CO₂ for different time periods in gigatonnes of carbon (GtC). Fossil CO₂ emissions include cement carbonation. The budget imbalance (BIM) provides a measure of the discrepancies among the nearly independent estimates. All values are rounded to the nearest 5 GtC and therefore columns do not necessarily add to zero. Uncertainties are reported as follows: E<sub>FOS</sub> is 5% of cumulative emissions; E<sub>LUC</sub> prior to 1959 is 1σ spread from the DGVMs, E<sub>LUC</sub> post-1959 is 0.7\*number of years (where 0.7 GtC yr<sup>-1</sup> is the uncertainty on the annual E<sub>LUC</sub> flux estimate); G<sub>ATM</sub> uncertainty is held constant at 5 GtC for all time periods; S<sub>OCEAN</sub> uncertainty is 20% of the cumulative sink (20% relates to the annual uncertainty of 0.4 GtC yr<sup>-1</sup>, which is ~20% of the current ocean sink); and S<sub>LAND</sub> is the 1σ spread from the DGVMs estimates.

Mean (GtC yr⁻¹)

<table><thead><tr><th></th><th></th><th>1750-2024</th><th>1850-2014</th><th>1850-2024</th><th>1960-2024</th><th>1850-2025</th></tr></thead><tbody><tr><td rowspan="3">Emissions</td><td>Fossil CO2 emissions (E<sub>FOS</sub>)</td><td>500±25</td><td>400±20</td><td>495±25</td><td>415±20</td><td>510±25</td></tr><tr><td>Land-use change emissions (E<sub>LUC</sub>)</td><td>280±65</td><td>235±55</td><td>250±60</td><td>110±45</td><td>250±60</td></tr><tr><td>Total emissions</td><td>780±70</td><td>635±60</td><td>745±65</td><td>525±50</td><td>755±65</td></tr><tr><td rowspan="3">Partitioning</td><td>Growth rate in atmos CO2 (G<sub>ATM</sub>)</td><td>310±5</td><td>235±5</td><td>290±5</td><td>230±5</td><td>295±5</td></tr><tr><td>Ocean sink (S<sub>OCEAN</sub>)</td><td>210±40</td><td>170±35</td><td>200±40</td><td>145±30</td><td>205±40</td></tr><tr><td>Terrestrial sink (S<sub>LAND</sub>)</td><td>190±50</td><td>150±40</td><td>175±50</td><td>120±30</td><td>175±50</td></tr><tr><td>Budget imbalance</td><td>BIM=E<sub>FOS</sub>+E<sub>LUC</sub>-(G<sub>ATM</sub>+S<sub>OCEAN</sub>+S<sub>LAND</sub>)</td><td>65</td><td>80</td><td>80</td><td>35</td><td>80</td></tr></tbody></table>

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<figure><img src="image_121.png" /></figure>

Table 9. Average annual growth rate in fossil CO₂ emissions over the most recent decade (2015-2024) and the previous decade (2005-2014). The data for the World include the cement carbonation sink. IAS are emissions from international aviation and shipping. The rest of the world is defined as World minus China, USA, India, EU27, and IAS.

<table><thead><tr><th></th><th>World</th><th>China</th><th>USA</th><th>India</th><th>EU27</th><th>OECD</th><th>Non-OEC<br>D</th><th>IAS</th><th>Rest of<br>the World</th></tr></thead><tbody><tr><td>2005-2014</td><td>2.1%</td><td>6.7%</td><td>-1.4%</td><td>6.4%-</td><td>2.2%</td><td>-1.0%</td><td>4.6%</td><td>1.9%</td><td>1.8%</td></tr><tr><td>2015-2024</td><td>0.8%</td><td>2.5%</td><td>-1.2%</td><td>3.6%</td><td>-2.5%</td><td>-1.5%</td><td>2.1%</td><td>-1.4%</td><td>0.6%</td></tr></tbody></table>
<figure><img src="image_122.png" /></figure>

Table 10. Major known sources of uncertainties in each component of the Global Carbon Budget, defined as input data or processes that have a demonstrated effect of at least ±0.3 GtC yr⁻¹.

<table><thead><tr><th>Source of uncertainty</th><th>Time scale (years)</th><th>Location</th><th>Evidence</th></tr></thead><tbody><tr><td colspan="4">Fossil CO2 emissions (EFOS; Section 2.1)</td></tr><tr><td>energy statistics</td><td>annual to decadal</td><td>global, but mainly China & major developing countries</td><td>(Korsbakken et al., 2016, Guan et al., 2012)</td></tr><tr><td>carbon content of coal</td><td>annual to decadal</td><td>global, but mainly China & major developing countries</td><td>(Liu et al., 2015)</td></tr><tr><td>system boundary</td><td>annual to decadal</td><td>all countries</td><td>(Andrew, 2020a)</td></tr><tr><td colspan="4">Net land-use change flux (ELUC; section 2.2)</td></tr><tr><td>land-cover and land-use change statistics</td><td>continuous</td><td>global; in particular tropics</td><td>(Houghton et al., 2012, Gasser et al., 2020, Ganzenmüller et al., 2022, Yu et al. 2022)</td></tr><tr><td>sub-grid-scale transitions</td><td>annual to decadal</td><td>global</td><td>(Wilkenskjeld et al., 2014, Bastos et al., 2021)</td></tr><tr><td>vegetation biomass</td><td>annual to decadal</td><td>global; in particular tropics</td><td>(Houghton et al., 2012, Bastos et al., 2021)</td></tr><tr><td>forest degradation (fire, selective logging)</td><td>annual to decadal</td><td>tropics; Amazon</td><td>(Aragão et al., 2018, Qin et al., 2021, Lapola et al., 2023)</td></tr><tr><td>wood and crop harvest</td><td>annual to decadal</td><td>global; SE Asia</td><td>(Arneth et al., 2017, Erb et al., 2018)</td></tr><tr><td>peat burning</td><td>multi-decadal trend</td><td>global</td><td>(van der Werf et al., 2010, 2017)</td></tr><tr><td colspan="4">Atmospheric growth rate (GATM; section 2.4) no demonstrated uncertainties larger than ±0.3 GtC yr⁻¹. The uncertainties in annual GATM have been estimated as ±0.2 GtC yr⁻¹, although the conversion of the growth rate into a global annual flux assuming instantaneous mixing throughout the atmosphere introduces additional errors (see Section 2.4.2).</td></tr><tr><td colspan="4">Ocean sink (SOCEAN; section 2.5)</td></tr><tr><td>sparsity in surface fCO2 observations</td><td>mean, decadal variability and trend</td><td>global, in particular southern hemisphere</td><td>(Gloege et al., 2021, Denvil-Sommer et al., 2021, Hauck et al., 2023a; Dong et al., 2024b)</td></tr></tbody></table>
<figure><img src="image_123.png" /></figure>

<table><tbody><tr><td>riverine carbon outgassing and its anthropogenic perturbation</td><td>annual to decadal</td><td>global, in particular partitioning between Tropics and South</td><td>(Aumont et al., 2001, Lacroix et al., 2020, Crisp et al., 2022)</td></tr><tr><td>Models underestimate interior ocean anthropogenic carbon storage</td><td>annual to decadal</td><td>global</td><td>(Friedlingstein et al., 2022a, this study, DeVries et al., 2023, Müller et al., 2023)</td></tr><tr><td>near-surface temperature and salinity gradients</td><td>mean on all time-scales</td><td>global</td><td>(Watson et al., 2020, Dong et al., 2022, Bellenger et al., 2023, Dong et al., 2024a)</td></tr><tr><td colspan="4">Land sink (SLAND; section 2.6)</td></tr><tr><td>strength of CO2 fertilisation</td><td>multi-decadal trend</td><td>global</td><td>(Wenzel et al., 2016; Walker et al., 2021)</td></tr><tr><td>response to variability in temperature and rainfall</td><td>annual to decadal</td><td>global; in particular tropics</td><td>(Cox et al., 2013; Jung et al., 2017; Humphrey et al., 2018; 2021)</td></tr><tr><td>nutrient limitation and supply</td><td>annual to multi-decadal</td><td>global</td><td>(Zaehle et al., 2014)</td></tr><tr><td>carbon allocation and tissue turnover rates</td><td>annual to decadal</td><td>global</td><td>(De Kauwe et al., 2014; O'Sullivan et al., 2022)</td></tr><tr><td>tree mortality</td><td>annual</td><td>global in particular tropics</td><td>(Hubau et al., 2021; Brienen et al., 2020)</td></tr><tr><td>response to diffuse radiation</td><td>annual</td><td>global</td><td>(Mercado et al., 2009; O'Sullivan et al., 2021)</td></tr></tbody></table>

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<figure><img src="image_124.png" /><figcaption>4197 Figures</figcaption></figure>

<figure><img src="image_125.png" /></figure>

4198

Figure 1. Surface average atmospheric CO₂ concentration (ppm). Since 1980, monthly data are from NOAA/GML (Lan et al., 2025a) and are based on an average of direct atmospheric CO₂ measurements from multiple stations in the marine boundary layer (Masarie and Tans, 1995). The 1958-1979 monthly data are from the Scripps Institution of Oceanography, based on an average of direct atmospheric CO₂ measurements from the Mauna Loa and South Pole stations (Keeling et al., 1976). To account for the difference of mean CO₂ and seasonality between the NOAA/GML and the Scripps station networks used here, the Scripps surface average (from two stations) was de-seasonalised and adjusted to match the NOAA/GML surface average (from multiple stations) by adding the mean difference of 0.667 ppm, calculated here from overlapping data during 1980-2012.

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<figure><img src="image_126.png" /></figure>

The global carbon cycle

<figure><img src="image_127.png" /></figure>

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4210

Figure 2. Schematic representation of the overall perturbation of the global carbon cycle caused by anthropogenic activities, averaged globally for the decade 2015-2024. See legends for the corresponding arrows. Fluxes estimates and their 1 standard deviation uncertainty are as reported in Table 7. The CDR estimate is for the year 2024. The uncertainty in the atmospheric CO₂ growth rate is very small (±0.02 GtC yr⁻¹) and is neglected for the figure. The anthropogenic perturbation occurs on top of an active carbon cycle, with fluxes and stocks represented in the background and taken from Canadell et al. (2021) for all numbers, except for the carbon stocks in coasts which is from a literature review of coastal marine sediments (Price and Warren, 2016). Fluxes are in GtC yr⁻¹ and reservoirs in GtC. This figure was produced by Nigel Hawtin.

4219
<figure><img src="image_128.png" /></figure>

<figure><img src="image_129.png" /><figcaption>**Figure 3.** Combined components of the global carbon budget as a function of time, for fossil CO₂ emissions (EFOS, including a small sink from cement carbonation; grey) and emissions from land-use change (ELUC; brown), as well as their partitioning among the atmosphere (GATM; cyan), ocean (SOCEAN; blue), and land (SLAND; green). The figure shows annual estimates of each flux (in GtC yr⁻¹) since the year 1850. The partitioning is based on nearly independent estimates from observations (for GATM) and from process model ensembles constrained by data (for SOCEAN and SLAND) and does not exactly add up to the sum of the emissions, resulting in a budget imbalance (BIM) which is represented by the difference between the bottom red line (mirroring total emissions) and the sum of carbon fluxes in the ocean, land, and atmosphere reservoirs. The EFOS estimate is based on a mosaic of different datasets and has an uncertainty of ±5% (±1σ). The ELUC estimate is from three bookkeeping models (Table 4) with uncertainty of ±0.7 GtC yr⁻¹. The GATM estimates prior to 1959 are from Joos and Spahni (2008) with uncertainties equivalent to about ±0.1-0.15 GtC yr⁻¹ and from Lan et al. (2025a) since 1959 with uncertainties of about +0.07 GtC yr⁻¹ during 1959-1979 and ±0.02 GtC yr⁻¹ since 1980. The SOCEAN estimate prior to 1959 is the average from Khatiwala et al. (2013) and DeVries (2014) with uncertainty of about ±30%. After 1959, it is the average of an ensemble of models (GOBMs) and an ensemble of f/CO₂-products (with adjustments, Table 4) with uncertainties of about ±0.4 GtC yr⁻¹. The SLAND estimate is the average of an ensemble of models (DGVMs) (Table 4) with uncertainties of about ±1 GtC yr⁻¹. See the text for more details of each component and their uncertainties.</figcaption></figure>
<figure><img src="image_130.png" /></figure>

<figure><img src="image_131.png" /></figure>

<figure><img src="image_132.png" /></figure>

<figure><img src="image_133.png" /></figure>

<figure><img src="image_134.png" /></figure>

<figure><img src="image_135.png" /></figure>

<figure><img src="image_136.png" /></figure>

4239

**Figure 4.** Components of the global carbon budget and their uncertainties as a function of time, presented individually for (a) fossil CO₂, including cement carbonation emissions (EFOS), (b) emissions from land-use change (ELUC), (c) growth rate in atmospheric CO₂ concentration (GATM), (d) the ocean CO₂ sink (SOCEAN), (e) the land CO₂ sink (SLAND), (f) the budget imbalance (BIM) that is not accounted for by the other terms. Individual estimates from the three bookkeeping models are shown as dashed lines for ELUC in panel (b). Positive values of SLAND and SOCEAN represent a flux from the atmosphere to land or the ocean. All data are in Gt yr⁻¹ with the uncertainty bounds representing ±1 standard deviation in shaded colour. Data sources are as in Figure 3. The red dots indicate our projections for the year 2025 and the red error bars the uncertainty in the 2025 projections (see methods).

4249
<figure><img src="image_137.png" /></figure>

<figure><img src="image_138.png" /><figcaption>Figure 5. Fossil CO₂ emissions for (a) territorial (solid lines) and consumption (dashed lines) emissions for the top three country emitters (USA, China, India) and for the European Union (EU27), (b) global emissions by fuel type, including coal, oil, gas, and cement, and cement minus cement carbonation (dashed), and (c) per-capita emissions the world and for the large emitters as in panel (a). Territorial emissions are from Andrew & Peters (2025), while consumption-based emissions are updated from Peters et al. (2011a). See Section 2.1 and Supplement S.1 for details of the calculations and data sources.</figcaption></figure>
<figure><img src="image_139.png" /></figure>

<figure><img src="image_140.png" /><figcaption>**Figure 6.** The 2015-2024 decadal mean components of the global carbon budget, presented for (a) fossil CO₂ emissions (EFOS), (b) land-use change emissions (ELUC), (c) the ocean CO₂ sink (SOCEAN), and (d) the land CO₂ sink (SLAND). Positive values for EFOS and ELUC represent a flux to the atmosphere, whereas positive values of SOCEAN and SLAND represent a flux from the atmosphere to the ocean or the land (carbon sink). In all panels, red colours represent a source (flux from the land/ocean to the atmosphere), blue colours represent a sink (flux from the atmosphere into the land/ocean). All units are in gC m⁻² yr⁻¹. Note the different scales in each panel. EFOS data shown is from GCP-GridFEDv2025.0 and does not include cement carbonation. The ELUC map shows the average ELUC from the three bookkeeping models plus emissions from peat drainage and peat fires. BLUE and LUCE provide spatially explicit estimates at 0.25° resolution. Gridded ELUC estimates for OSCAR are derived by spatially distributing their national data based on the spatial patterns of BLUE gross fluxes in each country (see Schwingshackl et al., 2022, for more details about the methodology). SOCEAN data shown is the average of un-adjusted GOBMs and /CO₂-products means, using GOBMs simulation A, no adjustment for bias and drift applied to the gridded fields (see Section 2.5). SLAND data shown is the average of the DGVMs for simulation S2 with the RSS adjustment included (see Section 2.6).</figcaption></figure>

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<figure><img src="image_141.png" /></figure>

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<figure><img src="image_143.png" /></figure>

<figure><img src="image_144.png" /></figure>

4274

Figure 7. Net CO₂ exchanges between the atmosphere and the terrestrial biosphere related to land use change.

4275 (a) Net CO₂ emissions from land-use change from the four countries with largest cumulative emissions since 1959. Values shown are the average of the three bookkeeping models, with shaded regions as ±1σ uncertainty.

4276 (b) Sub-components of E_LUC: (i) emissions from deforestation (including permanent deforestation and deforestation in shifting cultivation cycles), (ii) emissions from peat drainage & peat fires, (iii) removals from forest (re-)growth (including forest (re-)growth due to afforestation and reforestation and forest regrowth in shifting cultivation cycles), (iv) fluxes from wood harvest and other forest management (comprising slash and product decay following wood harvest, regrowth after wood harvest, and fire suppression), and (v) emissions and removals related to other land-use transitions. The sum of the five components is E_LUC shown in Figure 4b. (c) Sub-components of ‘deforestation (total)’ and of ‘forest (re-)growth (total)’: (i) deforestation in shifting cultivation cycles, (ii) permanent deforestation, (iii) forest (re-)growth due to afforestation and/or reforestation, and (iv) forest regrowth in shifting cultivation cycles.
<figure><img src="image_145.png" /></figure>

<figure><img src="image_146.png" /></figure>

4287

4288 **Figure 8.** Comparison of land-use flux estimates from bookkeeping models (BMs; following the GCB definition of E<sub>LUC</sub>), national GHG inventories (NGHGIs; following IPCC guidelines and thus including all carbon fluxes on managed land), and atmospheric inversion systems (considering fluxes on managed land only).

4289
4290 To compare BM results with NGHGIs, a translation is necessary for some subcomponents. (a) Net land-use fluxes, for which a translation of BMs is necessary, (b) subcomponents permanent deforestation, peat drainage & peat fires, and other transitions, which can be directly compared and (c) subcomponent forest (re-)growth & other forest management, for which a translation is necessary. The lines represent the mean of 3 BMs and 14 atmospheric inversion estimates, respectively; Shaded areas denote the full range across BM estimates and the standard deviation for atmospheric inversions, respectively. The subcomponent forest (re-)growth & other forest management includes removals from forest (re-)growth (permanent), emissions and removals from wood harvest & other forest management, and emissions and removals in shifting cultivation cycles. The translation of BM estimates to NGHGI estimates in (a) and (c) is done by adding the natural land sink in managed forests to the BM estimates (see also Table S10). The GCB definition of E<sub>LUC</sub> and the NGHGI definition of land-use fluxes are equally valid, each in its own context. For illustrative purposes we only show the translation of BM estimates to the NGHGI definition. NGHGI data are from the LULUCF data hub V3.1 (Melo et al. 2025).

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<figure><img src="image_147.png" /></figure>

<figure><img src="image_148.png" /><figcaption>Figure 9: Annual atmospheric CO₂ growth rates based on observations from the surface network (by NOAA (National Oceanic and Atmospheric Administration) and SIO (Scripps Institution of Oceanography), as well as using the Growth Rate from Satellite Observations (GRESO) approach using OCO-2 based XCO₂ observations in ppm yr⁻¹ with uncertainties. To obtain G_ATM, the surface observation-based growth rate in units of ppm yr⁻¹ is converted to units of GtC yr⁻¹ by multiplying by a conversion factor (CF) of 2.124 GtC per ppm, assuming instantaneous mixing of CO₂ throughout the atmosphere. The purple lines are the atmospheric growth rates (in GtC yr⁻¹) calculated as the sum of the fluxes derived by the atmospheric inversions. Note that the right hand axis shows the growth rate in GtC yr⁻¹, with intervals of the conversion factor.</figcaption></figure>

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<figure><img src="image_149.png" /></figure>

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a

<figure><img src="image_150.png" /></figure>

b

<figure><img src="image_151.png" /></figure>

4318 **Figure 10.** (a) The land CO₂ sink ($S_{LAND}$) estimated by individual DGVMs (thin green lines). The DGVM multi-model mean is shown as the thick green line. The $S_{LAND}$ budget estimate (black with ±1σ uncertainty), is the

4319 DGVM multi-model mean adjusted for the RSS bias (i.e. reduced by 19%). (b) Comparison of the

4320 anthropogenic atmosphere-ocean CO₂ flux showing the budget values of $S_{OCEAN}$ (black; with the uncertainty in

4321 grey shading), individual ocean models (royal blue), and the ocean $/CO₂$-products (cyan). Adjustments were

4322 applied to $S_{OCEAN}$ (black) for the known underestimation in GOBMs and the warm layer/cool skin effect for

4323 $/CO₂$-products. Individual model lines as well as GOBM and $/CO₂$-product ensemble means (thick cyan and

4324 royal blue lines) do not include these adjustments, with the exception of 2 $/CO₂$-products (UExP-FNN-U and

4325 JMA-MLR) that include temperature corrections as part of their air-sea CO₂ flux calculation (see section 2.5).

4326 Two $/CO₂$-products (Jena-MLS, LDEO-HPD) extend back to 1959. All $/CO₂$-products were adjusted for the pre-

4327 industrial ocean source of CO₂ from river input to the ocean, by subtracting a source of 0.65 GtC yr⁻¹ to make

4328 them comparable to $S_{OCEAN}$ (see Section 2.5). The bar-plot in the lower right illustrates the number of monthly

4329 gridded values in the SOCAT v2025 dataset (Bakker et al., 2025a). Grey bars indicate the number of grid cells

4330 in SOCAT v2024, and coloured bars indicate the newly added grid cells in v2025.

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<figure><img src="image_152.png" /></figure>

a

Bottom-up – Net Land Sink Anomaly 2024

<figure><img src="image_153.png" /></figure>

b

Inversions – Net Land Sink Anomaly 2024

<figure><img src="image_154.png" /></figure>

c

Bottom-up – Ocean Sink Anomaly 2024

<figure><img src="image_155.png" /></figure>

d

Inversions – Ocean Sink Anomaly 2024

<figure><img src="image_156.png" /></figure>

4333

Figure 11. Anomalies in land and ocean sinks for 2024. Maps show the 2024 fluxes relative to the 2015-2024 decadal mean. Units are gC m⁻² yr⁻¹. (a) The bottom-up anomaly in the net land flux combines both the anomaly in S<sub>LAND</sub> from DGVMs and in E<sub>LUC</sub> from bookkeeping models, although the E<sub>LUC</sub> contribution to the anomaly is minimal. Panel (b) shows the mean anomaly in the net land flux across 14 inversions. Panel (c) shows the mean anomaly from GOBMs and /CO₂ product ensemble means. The mean anomaly for GOBMs and /CO₂ products is first calculated, and then the mean of the two products is shown. Panel (d) shows the mean anomaly in ocean fluxes across 14 inversions.

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<figure><img src="image_157.png" /></figure>

<figure><img src="image_158.png" /><figcaption>Figure 12. Attribution of the atmosphere-ocean (SOCEAN) and atmosphere-land (SLAND) CO₂ fluxes to (a) increasing atmospheric CO₂ concentrations and (b) changes in climate, averaged over the previous decade 2015-2024. All data shown is from the processed-based GOBMs and DGVMs. Note that the sum of ocean CO₂ and climate effects shown here will not equal the ocean sink shown in Figure 6, which includes the fCO₂-products. No adjustments were applied to the DGVMs or GOBMs. See Supplement S.3.2 and S.4.1 for attribution methodology. Units are in gC m⁻² yr⁻¹ (note the non-linear colour scale). Positive values (blue) are CO₂ sinks, negative values (red) are CO₂ sources.</figcaption></figure>

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<figure><img src="image_159.png" /></figure>

<figure><img src="image_160.png" /><figcaption>**Figure 13.** The 2015-2024 decadal mean global net atmosphere-ocean and net atmosphere-land fluxes derived from the ocean models and $f\text{CO}_2$ products (y-axis, right and left pointing blue triangles respectively), and from the DGVMs (x-axis, green symbols), and the same fluxes estimated from the atmospheric inversions (purple symbols). The shaded distributions show the densities of the ensembles of individual estimates. The black central cross ('GCB') is the mean (±1σ) of $S_{\text{OCEAN}}$ and ($S_{\text{LAND}}$ − $E_{\text{LUC}}$) as assessed in this budget. The grey diagonal line represents the constraint on the global land + ocean net flux, i.e. global fossil fuel emissions minus the atmospheric growth rate from this budget ($E_{\text{FOS}}$ − $G_{\text{ATM}}$). The orange square represents the same global net atmosphere-ocean and atmosphere-land fluxes as estimated from the atmospheric $O_2$ constraint (the ellipse drawn around the central atmospheric $O_2$ estimate is a contour representing the 1σ uncertainty of the land and ocean fluxes as a joint probability distribution). Positive values are $\text{CO}_2$ sinks. Note that the inverse estimates have been scaled for a minor difference between $E_{\text{FOS}}$ and GridFEDv2025.1 (Jones et al., 2025). The 'GCB' central mean estimate includes the $S_{\text{LAND}}$ and $S_{\text{OCEAN}}$ global adjustments. The inversions and $f\text{CO}_2$ products include the river adjustment (see Section 2). No further adjustments were applied to the individual bottom-up estimates.</figcaption></figure>

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<figure><img src="image_161.png" /></figure>

<figure><img src="image_162.png" /><figcaption>**Figure 14.** CO₂ fluxes between the atmosphere and the Earth's surface separated between land and oceans, globally and in three latitude bands. The ocean flux is $S_{OCEAN}$ and the land flux is the net atmosphere-land fluxes from the DGVMs. The latitude bands are (top row) global, (2nd row) north (>30°N), (3rd row) tropics (30°S-30°N), and (bottom row) south (<30°S), and over ocean (left column), land (middle column), and total (right column). Estimates are shown for: process-based models (DGVMs for land, GOBMs for oceans); inversion systems (land and ocean); and fCO₂-products (ocean only). Positive values are CO₂ sinks. Mean estimates from the combination of the process models for the land and oceans are shown (black line) with ±1 σ of the model ensemble (grey shading). For the total uncertainty in the process-based estimate of the total sink, uncertainties are summed in quadrature. Mean estimates from the atmospheric inversions are shown (purple lines) with their full spread (purple shading). Mean estimates from the fCO₂-products are shown for the ocean domain (light blue</figcaption></figure>

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<figure><img src="image_163.png" /></figure>

4378 lines) with full model spread (light blue shading). The global SOCEAN (upper left) and the sum of SOCEAN in all

4379 three regions represents the anthropogenic atmosphere-to-ocean flux based on the assumption that the pre-

4380 industrial ocean sink was 0 GtC yr⁻¹ when riverine fluxes are not considered. This assumption does not hold at

4381 the regional level, where pre-industrial fluxes can be significantly different from zero. Hence, the regional

4382 panels for SOCEAN represent a combination of natural and anthropogenic fluxes.

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<figure><img src="image_164.png" /></figure>

<figure><img src="image_165.png" /></figure>

<figure><img src="image_166.png" /></figure>
<figure><img src="image_167.png" /></figure>

<table><tr><td>4386</td><td>Figure 15. Decadal mean (a) land and (b) ocean fluxes for RECCAP-2 regions over 2015-2024. For land fluxes, SLAND is estimated by the DGVMs (green bars), with the error bar as ±1σ spread among models. A positive SLAND is a net transfer of carbon from the atmosphere to the land. ELUC fluxes are shown for both DGVMs (green) and bookkeeping models (orange), again with the uncertainty calculated as the ±1σ spread. Note, a positive ELUC flux indicates a loss of carbon from the land. For the DGVMs, SLAND and ELUC are adjusted for RSS bias. The net land flux is shown for both DGVMs (green) and atmospheric inversions (purple), including the full model spread for inversions. The ocean sink (SOCEAN) is estimated by GOBMs (royal blue), CO2-products (cyan), and atmospheric inversions (purple). No adjustments were applied to GOBMs and CO2-products at regional scale. Uncertainty is estimated as the ±1σ spread for GOBMs, and the full model spread for the other two datasets. The dotted lines show the CO2-products and inversion results without river flux adjustment. Positive values are CO2 sinks.</td></tr><tr><td>4387</td><td></td></tr><tr><td>4388</td><td></td></tr><tr><td>4389</td><td></td></tr><tr><td>4390</td><td></td></tr><tr><td>4391</td><td></td></tr><tr><td>4392</td><td></td></tr><tr><td>4393</td><td></td></tr><tr><td>4394</td><td></td></tr><tr><td>4395</td><td></td></tr><tr><td>4396</td><td></td></tr><tr><td>4397</td><td></td></tr><tr><td>4398</td><td></td></tr></table>