Accelerated heatwave trends from nonlinear land-atmosphere interactions in midlatitude humid regions

Accelerated heatwave trends from nonlinear land-atmosphere interactions in midlatitude humid regions | 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 Accelerated heatwave trends from nonlinear land-atmosphere interactions in midlatitude humid regions Yinglin Tian, Jiangong Liu, Yu Huang, Pierre Gentine, Kai Kornhuber This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6585759/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 most extreme temperatures are increasing more rapidly than moderate ones, yet the physical mechanisms behind this acceleration remain unclear. Here, we show that nonlinear land–atmosphere interactions play a pivotal role in intensifying heatwave trends across midlatitude humid regions. Using an explainable machine learning framework, we quantify a nonlinear nature of these interactions, characterized by critical thresholds in temperature and soil moisture, beyond which heat extremes are strongly amplified. This behavior is evident across 30% of midlatitude humid areas, contributing to a 10% increase in individual heatwave magnitudes. In these regions, 15% of the accelerated rise in extreme temperatures is attributable to the increasing probability of crossing the critical thresholds—a value that rises to 53% in Central Europe, a prominent heatwave hotspot. We also find that biases in CMIP6 extreme heat projections stem from an underestimation of these nonlinear interaction processes, which is further led by a lagged soil moisture response during heatwave events. After statistically correcting these projections, we estimate that the difference between the most extreme and moderate temperature could be 4.2 ± 0.16 times greater than currently projected in midlatitude humid regions by the end of the 21st century. Earth and environmental sciences/Climate sciences/Climate change/Attribution Earth and environmental sciences/Climate sciences/Climate change/Climate and Earth system modelling Earth and environmental sciences/Climate sciences/Climate change/Projection and prediction Full Text Additional Declarations There is NO Competing Interest. Supplementary Files NonlinearSIversub.pdf Supplementary Information 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-6585759","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":483943011,"identity":"65211cbd-d3da-4560-bddd-31a40a835d10","order_by":0,"name":"Yinglin Tian","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0003-4134-1234","institution":"Potsdam Institute for Climate Impact Research (PIK)","correspondingAuthor":true,"prefix":"","firstName":"Yinglin","middleName":"","lastName":"Tian","suffix":""},{"id":483943012,"identity":"f789a71e-e09e-498c-bacf-3e16e88ddc46","order_by":1,"name":"Jiangong Liu","email":"","orcid":"https://orcid.org/0000-0002-4148-9522","institution":"Columbia University","correspondingAuthor":false,"prefix":"","firstName":"Jiangong","middleName":"","lastName":"Liu","suffix":""},{"id":483943013,"identity":"736eaa11-b270-408b-94e8-3f9c3c8d77ac","order_by":2,"name":"Yu Huang","email":"","orcid":"","institution":"Columbia University","correspondingAuthor":false,"prefix":"","firstName":"Yu","middleName":"","lastName":"Huang","suffix":""},{"id":483943014,"identity":"673f2d0b-d56a-40da-bb16-9908d206bc6d","order_by":3,"name":"Pierre Gentine","email":"","orcid":"https://orcid.org/0000-0002-0845-8345","institution":"Columbia University","correspondingAuthor":false,"prefix":"","firstName":"Pierre","middleName":"","lastName":"Gentine","suffix":""},{"id":483943015,"identity":"d5774666-9a47-45bc-86da-7e8f3cab5264","order_by":4,"name":"Kai Kornhuber","email":"","orcid":"","institution":"Lamont-Doherty Earth Observatory, Columbia University","correspondingAuthor":false,"prefix":"","firstName":"Kai","middleName":"","lastName":"Kornhuber","suffix":""}],"badges":[],"createdAt":"2025-05-03 20:25:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6585759/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6585759/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88875285,"identity":"f50f5609-e37e-4626-ad14-298fb3e13498","added_by":"auto","created_at":"2025-08-12 09:56:39","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1359715,"visible":true,"origin":"","legend":"Article File","description":"","filename":"NonlinearDraftversub.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6585759/v1_covered_547fe163-4bb3-4a65-beb9-4c61bebf8273.pdf"},{"id":88873680,"identity":"b5d6eec2-422b-4289-bf90-4ae9dd8d25dc","added_by":"auto","created_at":"2025-08-12 09:40:37","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":2313465,"visible":true,"origin":"","legend":"Supplementary Information","description":"","filename":"NonlinearSIversub.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6585759/v1/a7c6d719a13936d0f1019751.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Accelerated heatwave trends from nonlinear land-atmosphere interactions in midlatitude humid regions","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"nature-portfolio","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Nature Portfolio","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"ejp","reportingPortfolio":"","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6585759/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6585759/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"The most extreme temperatures are increasing more rapidly than moderate ones, yet the physical mechanisms behind this acceleration remain unclear. Here, we show that nonlinear land–atmosphere interactions play a pivotal role in intensifying heatwave trends across midlatitude humid regions. Using an explainable machine learning framework, we quantify a nonlinear nature of these interactions, characterized by critical thresholds in temperature and soil moisture, beyond which heat extremes are strongly amplified. This behavior is evident across 30% of midlatitude humid areas, contributing to a 10% increase in individual heatwave magnitudes. In these regions, 15% of the accelerated rise in extreme temperatures is attributable to the increasing probability of crossing the critical thresholds—a value that rises to 53% in Central Europe, a prominent heatwave hotspot. We also find that biases in CMIP6 extreme heat projections stem from an underestimation of these nonlinear interaction processes, which is further led by a lagged soil moisture response during heatwave events. After statistically correcting these projections, we estimate that the difference between the most extreme and moderate temperature could be 4.2 ± 0.16 times greater than currently projected in midlatitude humid regions by the end of the 21st century.","manuscriptTitle":"Accelerated heatwave trends from nonlinear land-atmosphere interactions in midlatitude humid regions","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-12 09:40:33","doi":"10.21203/rs.3.rs-6585759/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"d7760d5b-d014-4226-9267-79bed6cf9941","owner":[],"postedDate":"August 12th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":51386463,"name":"Earth and environmental sciences/Climate sciences/Climate change/Attribution"},{"id":51386464,"name":"Earth and environmental sciences/Climate sciences/Climate change/Climate and Earth system modelling"},{"id":51386465,"name":"Earth and environmental sciences/Climate sciences/Climate change/Projection and prediction"}],"tags":[],"updatedAt":"2025-08-12T09:40:33+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-12 09:40:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6585759","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6585759","identity":"rs-6585759","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}