Figure 1
Top: evolution of agricultural land (divided into cropland and pasture) and natural land cover relative to 1850. Bottom: annual net land-use change flux (ELUC) and fossil emissions (EFOS), with cumulative numbers since 1850 (bar plot on the right); data are from the Global Carbon Budget 2025 (GCB2025). Shading indicates the uncertainty range according to GCB2025
Figure 2
Net emissions from land-use change (ELUC) as estimated by different versions of the Global Carbon Budget (GCB). The text on the right mentions the most important changes introduced for different GCB versions since 2016. These include the use of different models and model versions (for model references see text), successive integration of regionally specific land-use change (LUC) maps, general updates in the global land-use reconstruction dataset HYDE (History Database of the Global Environment; denoted by different version numbers), and the inclusion of effects of environmental changes on carbon densities (as of GCB2025).
Figure 3
Components of the net land-use change CO2 flux (ELUC). The left panel shows an ELUC decomposition focused on drivers; estimates are derived from three bookkeeping models (BMs, as in the Global Carbon Budget 2025, Friedlingstein et al. (2026)). The right panel shows a decomposition and – for forests – a translation of the bookkeeping estimates that matches the definition of fluxes as used by the national greenhouse gas inventories (NGHGIs; which follow IPCC guidelines and thus include all CO2 fluxes on managed land). Sub-component fluxes are (i) emissions from deforestation (including permanent deforestation and deforestation in shifting cultivation cycles in the left panel, and including only permanent deforestation in the right panel), (ii) emissions from peat drainage and peat fires (same in both panels), (iii) emissions and removals related to other land-use transitions (same in both panels), (iv) removals from forest (re)growth (including forest (re)growth due to afforestation and reforestation and forest regrowth in shifting cultivation cycles) in the left panel, (v) fluxes from wood harvest and other forest management (comprising slash and wood product decay following wood harvest and regrowth after wood harvest) in the left panel, and (vi) forest flux (forest (re)growth and other forest management including the natural land sink in managed forests) in the right panel.
Figure 4
Graphical explanation of the interaction terms that arise when land-use changes—here exemplarily deforestation and reforestation—occur under changing environmental conditions. Two interaction terms can be distinguished: (i) Environmental changes create altered carbon stocks that land-use change acts upon—attributed to the net land-use change flux (ELUC = L + δL, i.e., the net land-use change flux including the environmental contribution) in the Global Carbon Budget; (ii) land-use change alters the vegetation distribution, which then responds differently to environmental changes and creates or destroys additional sinks or sources—attributed to the natural land sink (SLAND). Historically and on the global scale, environmental changes have increased the terrestrial carbon stocks. In the future, the beneficial effects on vegetation due to increasing atmospheric CO2 concentrations may be overcompensated for by detrimental climate change impacts (both regionally and globally), and areas that provided additional sinks in the past may turn into sources.
Figure 5
The (a) natural land sink (SLAND) and (c) net land-use change flux (ELUC) as defined by the Global Carbon Budget 2025 and interaction terms of land-use change and environmental changes: (b) replaced or re-established sinks/sources (RSS) and (d) the change in ELUC (δL) when calculated under transient as compared to fixed pre-industrial carbon densities (i.e., with vs without accounting for environmental changes). (e) The net land-atmosphere flux, FNET, is the sum of ELUC (corrected for δL) and SLAND (corrected for RSS). In all panels, negative fluxes indicate terrestrial sinks (flux from the atmosphere into land), and positive fluxes indicate sources. All fluxes are averages over 2015–2024. They amount to –2.4 PgC/yr for SLAND, –0.5 PgC/yr for RSS, 1.4 PgC/yr for ELUC, 0.3 PgC/yr for δL, and –1.0 PgC/yr for FNET. Panel (f) classifies regions based on whether FNET acts as a sink or a source (green vs. brown areas) and further distinguishes whether ELUC and SLAND is a sink or a source, respectively, and which of the two fluxes dominates in magnitude (plus signs in the legend denote sources, minus signs sinks). For example, the light green color covering half of the land surface indicates that the land, in net terms, takes up CO2, because the uptake by the natural land sink overcompensates the emissions from land-use change. The supplemental material shows the maps for the 1960s and for 2024 for comparison. All fluxes are based on the Global Carbon Budget 2025 (Friedlingstein et al., 2026) except for δL, which is calculated only with the bookkeeping model BLUE following Dorgeist et al. (2024).
Figure A.1
Same as Figure 5, but averaged over the years 1960–1969, the decade in which the global natural land sink, SLAND, had grown large enough to overcompensate the net land-use change flux, ELUC, which is globally a strong emission term. The fluxes amount to –0.9 PgC/yr for SLAND, –0.1 PgC/yr for RSS, 1.4 PgC/yr for ELUC, 0.2 PgC/yr for δL, and 0.4 PgC/yr for FNET.
Figure A.2
Same as Figure 5, but for the year 2024. Note that the land-use forcing for 2024, on which the net land-use change flux (ELUC) is based, is extrapolated from recent trends (Friedlingstein et al., 2025). Compared to Fig. 4, the detrimental impacts of hot-dry El Niño conditions on top of global warming in particular in the Amazon become apparent for the natural land sink and the replaced or re-established sinks/sources term (RSS). The fluxes amount to –1.9 PgC/yr for SLAND, –0.4 PgC/yr for RSS, 1.2 PgC/yr for ELUC, 0.3 PgC/yr for δL, and –0.6 PgC/yr for FNET.