Low Latency Global Carbon Budget Reveals Late 2024 Carbon Losses and Contrasting Early 2025 Land Sink Recovery Signals

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ABSTRACT The 2023/24 El Niño strongly reduced land carbon uptake, but the persistence of this anomaly after surface cooling remains uncertain. Here we quantify the July 2024–June 2025 global CO 2 budget using low‐latency fossil emission estimates, three DGVMs, machine learning ocean flux emulators and OCO‐2‐constrained atmospheric inversions. The atmospheric CO 2 growth rate was 2.62 ± 0.08 ppm yr −1 , 6.5% above the 2013–2022 July‐to‐June mean. DGVMs estimate that the net land sink was 1.32 ± 0.19 GtC yr −1 weaker than the 2015–2022 July‐to‐June mean, whereas combining bottom‐up and top‐down constraints gives a smaller deficit of 0.49 GtC yr −1 . The annual anomaly is dominated by late‐2024 land carbon losses. Early‐2025 recovery, however, is method‐dependent: DGVMs retain a weak annual land‐sink deficit, while all inversions indicate fluxes close to the reference mean and a stronger‐than‐normal northern sink in late spring 2025. Ocean uptake shows no global weakening. A statistical decomposition links global land flux variability mainly to temperature, with terrestrial water storage contributing more strongly at regional scales. These results identify Northern Hemisphere land‐sink recovery as a central uncertainty in low‐latency carbon‐budget assessments.