Continental arc volcanism fueled Middle Permian warming

The Middle Permian was characterized by a major climatic warming trend that heralded the end of the late Paleozoic Ice Age, as well as by widespread marine anoxia during the Capitanian biotic crisis. Although the Emeishan large igneous province (ELIP) has been implicated as a potential driver of this warming, its role remains contentious. We present a comprehensive analysis of mercury abundance and isotopes, along with zircon geochemistry, from tuffs interbedded in a Middle Permian deep-water succession from South China. Our data reveal sustained continental arc volcanism (CAV) prior to the ELIP eruptions that coincided with the Middle Permian warming, suggesting a potential causal relationship between them. Supported by Carbon-Oxygen-Phosphorus-Sulfur-Evolution modeling, we propose that globally increased CAV may have released sufficiently large quantities of CO2 to the atmosphere to trigger climate warming, ultimately leading to marine anoxia and biotic crisis. Our findings challenge the prevailing view of the ELIP as the sole cause of the Middle Permian warming and highlight the potential importance of CAV in Earth’s climate history.