Select earthquake forecasting models demonstrate consistency with decadal prospective observations in California

Select earthquake forecasting models demonstrate consistency with decadal prospective observations in California | 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 Select earthquake forecasting models demonstrate consistency with decadal prospective observations in California José Bayona, Francesco Serafini, Fábio Silva, Pablo Iturrieta, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8653631/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 Aftershock and earthquake forecasting systems are now operationalized by agencies in several countries, providing situational awareness to decision-makers and the public. To ensure that forecasts follow the best science available, the underlying models require rigorous testing against prospective data and benchmarking. Between August 2007 and August 2018, 27 time-varying forecasting models, including the types used for Operational Earthquake Forecasting (OEF), were automatically operated as part of a multi-institutional project by the Collaboratory for the Study of Earthquake Predictability (CSEP), generating an unprecedented database of over 50,000 next-day M w ≥ 3.95 seismicity forecasts in California. Here, we comprehensively evaluate their predictive skills against 597 prospective M w ≥ 3.95 earthquakes using community-vetted statistical methods. We find that approximately one-quarter, two-thirds, and 95% of the models produced forecasts consistent with the number, locations, and magnitudes of observed earthquakes, respectively, marking a significant milestone in earthquake predictability research and building confidence in their use for continuous OEF. Furthermore, newer models and models calibrated on small(er) earthquakes exhibited the best relative performances, demonstrating improved earthquake forecasting over time. We provide detailed recommendations and benchmarking data to support the development of OEF systems worldwide. Earth and environmental sciences/Solid Earth sciences/Seismology Earth and environmental sciences/Natural hazards Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementarymaterialNatComms.pdf Supplementary material to "Select earthquake forecasting models demonstrate consistency with decadal prospective observations in California" 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-8653631","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":581280638,"identity":"c058aeee-0373-495b-b6b5-52e9e3b28390","order_by":0,"name":"José 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