Six-fold increase of atmospheric pCO(2) during the Permian–Triassic mass extinction

The Permian–Triassic mass extinction was marked by a massive release of carbon into the ocean-atmosphere system, evidenced by a sharp negative carbon isotope excursion. Large carbon emissions would have increased atmospheric pCO(2) and caused global warming. However, the magnitude of pCO(2) changes during the PTME has not yet been estimated. Here, we present a continuous pCO(2) record across the PTME reconstructed from high-resolution δ(13)C of C(3) plants from southwestern China. We show that pCO(2) increased from 426 +133/−96 ppmv in the latest Permian to 2507 +4764/−1193 ppmv at the PTME within about 75 kyr, and that the reconstructed pCO(2) significantly correlates with sea surface temperatures. Mass balance modelling suggests that volcanic CO(2) is probably not the only trigger of the carbon cycle perturbation, and that large quantities of (13)C-depleted carbon emission from organic matter and methane were likely required during complex interactions with the Siberian Traps volcanism.