Constraining near-term projections of the South Asian high and Afro-Asian summer monsoon rainfall

Constraining near-term projections of the South Asian high and Afro-Asian summer monsoon rainfall | 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 Constraining near-term projections of the South Asian high and Afro-Asian summer monsoon rainfall Yanyan Huang, Dapeng Zhang, Botao Zhou, Qiaohong Sun, Huijun Wang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7565196/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 Reliable projections of Afro-Asian summer monsoon precipitation (AfroASMP) are critical for sustaining regional development and managing climate risks for billions of people. The complex historical variability of AfroASMP highlights the central role of dynamical circulations, alongside the favorable thermodynamic conditions associated with the centurial global warming. We identify that up to 80% of the variance in AfroASMP over past six decades is dynamically dominated by the South Asian High (SAH), an extensive upper-tropospheric mode spanning West Africa to the western Pacific. Using a multi-model weighting scheme, the constrained near-term SAH projects a larger amplitude than raw simulations across three emission scenarios (SSP1-2.6, SSP2-4.5, SSP5-8.5). SAH-based constraints indicate a reduction in AfroASMP of 10–50 mm, with the largest decrease in heavy rainfall over Africa (54%) under SSP5-8.5, and increases in dry conditions over India and North China (~ 20%). The framework offers physically grounded evidence for climate adaptation and policy decisions. Earth and environmental sciences/Climate sciences/Climate change/Projection and prediction Earth and environmental sciences/Climate sciences/Atmospheric science/Atmospheric dynamics Full Text Additional Declarations There is NO Competing Interest. Supplementary Files Supportinginformation.docx Supplementary table and figures 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-7565196","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":517183948,"identity":"0a391a40-8020-4d5e-b652-92b0521838f4","order_by":0,"name":"Yanyan 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