Storyline attribution of fire weather during the 2025 Mediterranean summer

Storyline attribution of fire weather during the 2025 Mediterranean summer | 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 Storyline attribution of fire weather during the 2025 Mediterranean summer Linda van Garderen, Dalena León Fon Fay, Victoria Dietz, Willem Jan van de Berg, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9252889/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 The Mediterranean region is a climate change hotspot where increasing temperatures and changing hydroclimate are intensifying wildfire risk. The extreme fire season of summer 2025 provides a timely case to assess the role of anthropogenic climate change in shaping fire-conducive atmospheric conditions. Here, we apply a spectrally nudged storyline approach to conditionally attribute the thermodynamic contribution of climate change to the Fire Weather Index during July–August 2025, for past and future climate states. We find a robust increase in fire weather across the Mediterranean under climate change. The strongest and most spatially coherent signal is driven by temperature increases, while reductions in relative humidity and precipitation further amplify fire-conducive conditions in specific regions. These results demonstrate that climate change has substantially intensified the meteorological conditions conducive to wildfires during the 2025 Mediterranean summer. More broadly, this study highlights the value of conditional storyline attribution for linking physically driven climate changes to impact-relevant metrics such as fire weather. Earth and environmental sciences/Climate sciences/Climate change/Climate and Earth system modelling Earth and environmental sciences/Climate sciences/Climate change/Attribution Full Text Additional Declarations There is NO Competing Interest. Supplementary Files vanGarderen2026Supplementarymaterials.pdf Supplementary Materials 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. 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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-9252889","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":636291947,"identity":"5d2cd002-195a-4763-95e2-5653453f5a4e","order_by":0,"name":"Linda van 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The extreme fire season of summer 2025 provides a timely case to assess the role of anthropogenic climate change in shaping fire-conducive atmospheric conditions. Here, we apply a spectrally nudged storyline approach to conditionally attribute the thermodynamic contribution of climate change to the Fire Weather Index during July–August 2025, for past and future climate states. We find a robust increase in fire weather across the Mediterranean under climate change. The strongest and most spatially coherent signal is driven by temperature increases, while reductions in relative humidity and precipitation further amplify fire-conducive conditions in specific regions. \r\nThese results demonstrate that climate change has substantially intensified the meteorological conditions conducive to wildfires during the 2025 Mediterranean summer. 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