Global Warming and Mass Extinctions Associated With Large Igneous Province Volcanism

Abstract

The coincidence of large igneous province (LIP) eruptions with at least three, if not all, of the Big Five biotic crises of the Phanerozoic implies that volcanism is a key driver of mass extinctions. Many LIP-induced extinction scenarios invoke global warming, caused primarily (but not exclusively) by greenhouse gases emitted at the site of LIP emplacement and by contact metamorphism of carbon-rich host rocks. Here we explore (1) the climate-changing products of volcanism including sulfur dioxide (SO 2 ), carbon dioxide (CO 2 ) and methane (CH 4 ) from eruptions, contact metamorphism, and melting (dissociation) of gas hydrates; (2) their deadly effects, including marine anoxia and thermal stress; (3) increasingly sophisticated paleotemperature proxies (e.g., δ 18 O of shell material) through case studies of the best-known LIP-warming-extinction nexi; and (4) global warming through the lens of the putative Anthropocene extinction. End Cretaceous Deccan Traps Warming (+4°C) No −2‰ Note: The Big Five extinction events are highlighted in bold text. PDD = Pripyat-Dnieper-Donets rift system; CAMP = Central Atlantic Magmatic Province. Modified from Bond and Grasby (2017).

Volcanic Climate Warming Through Radiative and Dynamical Feedbacks of SO2 Emissions

“…Indeed, thermal maxima or hyperthermal events have occurred concurrently or near in time to several flood basalt eruptions/large igneous province emplacements through Earth's history. These include the Permian‐Triassic, Paleocene‐Eocene, and others and have been linked to major eruptions such as the Siberian Traps and North Atlantic Igneous Province, respectively (Bond & Sun, 2021; Gutjahr et al., 2017). As with the MMCO and CRB, a great deal of CO 2 is necessary to match paleotemperature proxies from these events, and there remains a dispute if sufficient CO 2 was emitted to explain these warm climates (Armstrong McKay et al., 2014; Self et al., 2006; Sobolev et al., 2011).…”

“…Given our results, it seems more plausible that other factors following the CRB eruption (e.g., the drawdown of CO 2 and the end of transient additional warming through the response to SO 2 emissions) were proximate to the extinction, rather than cooling driven by volcanic aerosols from the CRB eruptions (but it would be important to test this with more comprehensive aerosol microphysical parameterizations (Timmreck et al., 2010)). However, most of the past extinctions associated with flood basalt eruptions are believed to be due to associated climate warming (Bond & Sun, 2021; Courtillot & Renne, 2003; Reichow et al., 2009; Sobolev et al., 2011; Wignall, 2001). Indeed, past mass extinctions are correlated with ≥5.2°C temperature increases, which our eruption simulation briefly exceeds (Song et al., 2021).…”

“…The climate impact of such eruptions is still being debated in the literature with the cooling provided by shortwave sunlight reflection from H 2 SO 4 aerosols balanced against the warming influence of CO 2 emissions (Armstrong McKay et al., 2014; Black et al., 2018; Schmidt et al., 2016; Self et al., 2005, 2006). Such eruptions have been implicated in producing “hyperthermal” periods in Earth's history such as the Permian‐Triassic hothouse and the Paleocene‐Eocene Thermal Maximum, but the volume of emitted CO 2 seems insufficient for such warming (Bond & Sun, 2021; Gutjahr et al., 2017).…”

“…They have covered vast areas with basalt, released massive amounts of climatically‐relevant gases into the atmosphere, and are nearly contemporaneous with many of Earth's mass extinctions or ocean anoxic events (Courtillot & Renne, 2003; Sobolev et al., 2011; Wignall, 2001). Flood basalts appear common on other terrestrial worlds in the Solar System (Bond & Sun, 2021; Head et al., 2011; Jaeger et al., 2010; Lancaster et al., 1995; O’Hara, 2000). Unlike explosive eruptions of stratovolcanoes such as Toba, Tambora, and Pinatubo that last only for hours to weeks, flood basalt eruptions continue for years if not millenia (Barry et al., 2010; Courtillot & Renne, 2003; Jerram & Widdowson, 2005).…”

Longer-term terrestrial responses in the aftermath of the end-Cretaceous mass extinction

“…The sulfate aerosols would be then considered as instantaneous in terms of geological time and are almost impossible to be preserved or recognized in the geological record. Such extremely short-lived events are unlikely to be recorded even in high-resolution paleothermometry studies, where decadal-centennial sampling is extremely difficult to make (Schmidt et al, 2016;Bond and Sun, 2021).…”