Improved Scaling and Impact Metrics for Euro-Atlantic Atmospheric Rivers

Improved Scaling and Impact Metrics for Euro-Atlantic Atmospheric Rivers | 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 Improved Scaling and Impact Metrics for Euro-Atlantic Atmospheric Rivers Venugopal Thandlam, Erik Sahlée, Anna Rutgersson This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7876106/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 11 You are reading this latest preprint version Abstract Atmospheric rivers (AR) are essential to the global water cycle, significantly impacting regional precipitation patterns and extreme weather events. Existing AR scales, while valuable, often lack regional specificity, particularly in capturing the nuances of ARs in subpolar regions. This study addresses these limitations by developing an improved AR scale and impact metrics tailored to the Euro-Atlantic region. Using high-resolution reanalysis data and the Bayesian AR Detector, we analyse AR characteristics and highlight contrasts between Pacific and Atlantic ARs. Recognising the limitations of the current AR scale developed by the Centre for Western Weather and Water Extremes, we introduce the new Uppsala University AR scale (NS), specifically designed for the Euro-Atlantic region. The NS incorporates a lower integrated water vapour threshold, equal weights for all categories, and a 72-hour persistence, reflecting regional AR behaviour more accurately. The study proposes alternative impact metrics - AR Severity Index (ARSI), ARSI-kinetic, and Risk Index - to comprehensively assess AR impacts. While ARSI focuses on physical strength, the Risk Index combines intensity with contextual factors for a broader view of overall risk. These refined metrics and the region-specific AR scale enhance understanding of AR impacts and hazards in the Euro-Atlantic region, contributing to improved forecasting, disaster preparedness, and water resource management. Earth and environmental sciences/Climate sciences Earth and environmental sciences/Environmental sciences Earth and environmental sciences/Hydrology Earth and environmental sciences/Natural hazards Atmospheric River Bayesian AR Detector Euro-Atlantic Uppsala University AR scale ARSI ARSI-kinetic Risk Index Full Text Additional Declarations No competing interests reported. Supplementary Files Supplementaryinformation.pdf Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 05 Jan, 2026 Reviews received at journal 03 Jan, 2026 Reviewers agreed at journal 13 Dec, 2025 Reviewers agreed at journal 13 Nov, 2025 Reviews received at journal 13 Nov, 2025 Reviewers agreed at journal 03 Nov, 2025 Reviewers invited by journal 30 Oct, 2025 Editor assigned by journal 30 Oct, 2025 Editor invited by journal 24 Oct, 2025 Submission checks completed at journal 19 Oct, 2025 First submitted to journal 19 Oct, 2025 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-7876106","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":542975322,"identity":"a2a6b39a-20ae-433b-a964-db8ef101f964","order_by":0,"name":"Venugopal 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