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Paleotemperatures of surface seawater are calculated from multiple proxies, including oxygen isotopes from carbonate and apatite fossil shells (δ 18O), carbonate clumped isotopes (Δ47), and organic geochemical proxies such as TEX 86 (see Methods). Within each time interval, the largest magnitude of temperature change and its duration and rate are quantified. For this study, a paleotemperature database is constructed for 45 approximately uniform time intervals (averaging ~10 Myr) spanning the late Ordovician (~450 Ma) to the early Miocene (~15 Ma) (Supplementary Data 1). These data allow investigation of the role that temperature change played in past extinctions. Paleotemperature data for the Phanerozoic have increased in abundance enormously over the past two decades, furnishing information for each geologic stage in post-Cambrian periods 12. Although the temporal coincidence between climate change and extinction is clear, there is a paucity of quantitative analysis investigating the precise relationship between magnitudes and rates of temperature change and extinction through the Phanerozoic Eon.
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The Permian-Triassic mass extinction (~252 Ma), the largest of the Phanerozoic 10, occurred within a short interval of ~60,000 years and was associated with rapid climate warming 8, 11.
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Of the Big Five extinctions, for example, the end-Ordovician mass extinction (~443 Ma) was related to a short-lived cooling event accompanied by a glaciation maximum and a major drop in sea level 7, 9. A large body of evidence has focused on abrupt climate change (both warming and cooling) as a direct or indirect mechanism that drove many mass and minor extinctions 3, 4, 5, 6, 7, 8. Our findings predict that a temperature increase of 5.2 ☌ above the pre-industrial level at present rates of increase would likely result in mass extinction comparable to that of the major Phanerozoic events, even without other, non-climatic anthropogenic impacts.įive large-magnitude mass extinctions (the “Big Five”) have occurred during the past 450 million years (Myr) 1, where the estimated extinction of marine animals for each event was over 75% at the species level 2. The significant relationship between temperature change and extinction still exists when we exclude the five largest mass extinctions of the Phanerozoic. Major mass extinctions in the Phanerozoic can be linked to thresholds in climate change (warming or cooling) that equate to magnitudes >5.2 ☌ and rates >10 ☌/Myr. The results show that both the rate and magnitude of temperature change are significantly positively correlated with the extinction rate of marine animals. Here, we analyze magnitudes and rates of temperature change and extinction rates of marine fossils through the past 450 million years (Myr). However, the quantitative relationship between temperature change and extinction is unclear. Climate change is a critical factor affecting biodiversity.