Northern Hemispheric atmospheric blocking representation in Community Earth System Model Large Ensemble 2

Northern Hemispheric atmospheric blocking representation in Community Earth System Model Large Ensemble 2 | 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 Research Article Northern Hemispheric atmospheric blocking representation in Community Earth System Model Large Ensemble 2 Prasad B. Shelke, James A. Renwick This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7450441/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Atmospheric blocking, a persistent high-pressure system that disrupts the westerly flow of jet streams, plays a critical role in driving extreme weather events but remains poorly represented in climate models. For the first time, this study assesses the representation of blocking in a large ensemble (100 members) using the Community Earth System Model Large Ensemble 2 (LENS2). A two-dimensional blocking detection method is used to analyze blocking frequency in LENS2 for the present-day (1980–2014) and future (2066–2100) periods. Comparisons with reanalysis datasets (ERA5 and NCEP2) reveal that LENS2 successfully reproduces the spatial distribution of blocking events over the Northern Hemisphere but exhibits region-dependent biases in frequency. Overall, winter blocking representation in LENS2 is found to be better than in previous models, while significant biases persist for the summer season. Future projections in LENS2 under the SSP370 scenario suggest a decrease in summer (winter) blocking by 2.5% (20%) by the end of the 21st century. However, summer blocking frequency is projected to increase over certain existing blocking-prone regions, such as Europe (+ 22%), the Pacific (+ 20%), and Russia (+ 12%), accompanied by an overall eastward shift in blocking centers in the future. Atmospheric Sciences Climate Analysis and Modeling Climatology Atmospheric blocking Extreme weather events Community Earth System Model Large Ensemble 2 (LENS2) 2D blocking detection Eastward shift of blocking centers under SSP370 Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted 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-7450441","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":505072193,"identity":"9f795338-ba33-4769-bb7c-cabf8b5bc013","order_by":0,"name":"Prasad B. 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