EARTH SYSTEM MODELLING OF EXPLOSIVE VOLCANISM DURING THE CARBONIFEROUS-PERMIAN TRANSITION

The peak of the LPIA coincided with anomalously low pCO2, but driver(s) for the CO2 drawdown remain debated. The direct and indirect effect of frequent explosive volcanism surrounding the equatorial Pangaea may have provided the nutrient feedbacks that led to increased (marine) organic carbon burial and reduced CO₂ levels. However, this idea has not been tested against observed data, for example gas flux and nutrient load. In this study, we performed a number of sensitivity tests in an Earth system model of intermediate complexity, cGENIE (carbon-centric Grid-Enabled Integrated Earth system model) with data-driven estimates of SO₂ and CO₂ fluxes to assess their effects on the climate, as well as elevated Fe flux to evaluate their impact on marine productivity. We hypothesize that enhanced Fe reactivity of atmospheric dust through explosive volcanism may have stimulated biological productivity, thereby enhancing organic carbon burial and leading to the reduction of atmospheric CO₂ levels and amplifying global cooling at the peak of the Late Paleozoic Ice Age.