Fig. 1: Re-evaluation of Earth’s carbon budget.
a,b, Earth’s carbon budget recalculated using our ‘Weighted-T’ regression model of terrestrial carbon exchange and a simple ocean model (a) and a comparison between the observed and our modelled atmospheric growth rate of CO2 (b). Reported annual fossil fuel (Frep, including cement effects) emissions are from the Global Carbon Project 20215. The atmospheric CO2 growth rate (AGRobs) is calculated from the average of observed CO2 concentrations at Mauna Loa and the South Pole observatories39. The ocean sink (Omod) is determined using a pulse-response model driven with observed CO2 concentrations33. The net land carbon exchange (Bnet,mod) is derived from the ‘Weighted-T’ model (see text). Annual average fluxes (dots) are shown at the midpoint of each year and five-year running means (solid lines) are applied to all data to guide the eye. b, Comparison of the observed AGR to the growth rate calculated as AGRmod = Frep − Omod − Bnet,mod.
