Continental-scale wildfires during end-Triassic greenhouse warming

Continental-scale wildfires during end-Triassic greenhouse warming | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Continental-scale wildfires during end-Triassic greenhouse warming Bas van de Schootbrugge, Teuntje Hollaar, Matthew Kent, Barry Lomax, and 15 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8211214/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Two-hundred-million years ago, the emission of an estimated 100,000 Gt of CO2 during pulsed eruptions in the Central Atlantic Magmatic Province had dire consequences for the biosphere driving the end-Triassic mass-extinction (ETME). Palynological assemblages obtained from drill cores in Germany, Luxemburg, Denmark and the UK that span the extinction event exhibit a remarkable darkening of pollen and spores that is at odds with simple thermal maturation. Here, we investigate this latest Triassic “Dark Zone”, using the Palynomorph Darkening Index (PDI) obtained from trilete fern spores and Classopollis pollen. Coinciding with a collapse of forest communities and the spread of a fern-dominated pioneer vegetation, PDI reaches peak darkness in the Germanic Triletes Beds and equivalent strata elsewhere. Comparison of PDI records from fossil pollen and spores to the results of controlled heating experiments of modern Lycopodium spores indicates that latest Triassic darkening of palynomorphs was caused by surface fires carried in fern savannahs. Frequent wildfires were widespread in Europe during the ETME based on elevated levels of micro-charcoal and pyrolytic polycyclic aromatic hydrocarbons (PAHs) during the “Dark Zone”. Continental-scale wildfires during the end-Triassic mass-extinction suggests intense climate change-induced heat stress on vegetation contributed to the collapse of terrestrial ecosystems. Earth and environmental sciences/Ecology/Palaeoecology Earth and environmental sciences/Ecology/Fire ecology Earth and environmental sciences/Climate sciences/Palaeoclimate Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryData1.xlsx Dataset 1 SupplementaryData2.xlsx Dataset 2 Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8211214","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":553442438,"identity":"4dd12423-6e2e-4c32-9ca4-740ac7483171","order_by":0,"name":"Bas van de 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