Weathering of the Emeishan Large Igneous Province Enhanced the Nutrient Flux to the Oceans and Led to Late Permian Climate Cooling

Abstract Mafic continental large igneous provinces (LIPs) erupted rapidly and may have overwhelmed Earth's atmospheric and biospheric systems. However, the exact balance and interplay between short‐term climate warming caused by CO 2 emissions and long‐term cooling due to LIP weathering remains poorly understood. To investigate the influence of LIP emplacement on long‐term climate change, we quantified the mass fluxes during the late Permian associated with the Emeishan LIP and its weathering products in the western Yangtze Cratonic Basin of southwestern China. The minimum value of the average denudation rate of the Emeishan LIP during the late Permian (Wuchiapingian) was 170.8 t/km 2 /yr, indicating enhanced capacity for atmospheric CO 2 consumption at that time. The estimated minimum dissolved element fluxes from the Emeishan LIP to the surface ocean were 2.29 × 10 6 t/yr Si, 11.7 × 10 3 t/yr P, and 68 × 10 3 t/yr Fe, which account for 1.3%–3.4% of the fluxes from modern global rivers. These high nutrient fluxes led to an atmospheric CO 2 removal rate of 8.5–85 × 10 6 t/yr through enhanced biological productivity, as estimated by the Fe fertilization model and dissolved Fe flux. This rate is approximately one order of magnitude higher than those resulting from Emeishan LIP basalt weathering and accounts for 0.05%–0.5% of the modern global CO 2 sink, which could have led to a reduction in atmospheric CO 2 . Our results highlight the key role of LIPs in modulating Earth's climate over long time periods and in driving long‐term cooling due to enhanced CO 2 drawdown caused by enhanced nutrient input to the surface ocean.