Climate migration in Europe? Evidence from drought exposure and internal migration in Italy

Climate migration in Europe? Evidence from drought exposure and internal migration in Italy | 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 Climate migration in Europe? Evidence from drought exposure and internal migration in Italy Emre Karabulutoğlu, Lorenzo Casprini, Raya Muttarak This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8487713/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 In recent years, studies on climate-induced migration have proliferated, but the focus has been mainly on low- and middle-income countries. This paper fills this gap by examining whether climate-driven migration patterns emerge in high-income settings, specifically Italy, one of the European countries most severely affected by climate change due to its Mediterranean location. Using annual bilateral migration flow data from the Italian National Institute of Statistics (ISTAT) for the period 2002-2023, drawn from the National Register of the Resident Population across 104 provinces (NUTS-3 level), and combining these data with drought severity indices (SPEI and PDSI), we examine how worsening climatic conditions affect internal migration within Italy. We adopt a panel data framework using a Poisson pseudo-maximum likelihood estimator, which allows us to capture both spatial and temporal variation in climate shocks and migration responses across provinces and regions. Our findings yield three main insights. First, we find robust evidence that drought exposure drives internal migration flows, showing that even high-income countries with greater adaptive capacity are not immune to climate-induced mobility. Translating the estimated effects into population counts shows that drought exposure over the past two decades is associated with several hundred thousand additional inter-provincial moves, with implied effects exceeding 560,000 migrants in high-exposure settings. Additional analyses also indicate higher international out-migration from drought-affected provinces, challenging the view that climate migration is primarily a concern of lower-income countries. Second, we reveal significant heterogeneity by citizenship status: foreign citizens display a markedly higher propensity to migrate in response to adverse climatic conditions than Italian citizens. Third, we find that local economic structure plays a crucial role, with drought-induced out-migration being strongest in middle-income regions rather than in the poorest or richest areas. Analyses of agricultural dependence reveal similar non-linear patterns, and further evidence indicates that drought affects migration by depressing local incomes and widening income gaps relative to potential destinations. Together, these results have important implications for climate adaptation policy, highlighting the need for proactive planning and early warning systems to anticipate and manage climate-induced movements. Earth and environmental sciences/Environmental social sciences/Climate-change impacts Earth and environmental sciences/Environmental social sciences/Environmental economics Earth and environmental sciences/Environmental social sciences/Climate-change adaptation Scientific community and society/Social sciences/Economics Scientific community and society/Social sciences/Interdisciplinary studies Full Text Additional Declarations There is NO Competing Interest. 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-8487713","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":571409222,"identity":"12472b4d-35ef-4f05-aa02-53905afb8f1b","order_by":0,"name":"Emre Karabulutoğlu","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0001-5667-5400","institution":"TOBB University of Economics and Technology","correspondingAuthor":true,"prefix":"","firstName":"Emre","middleName":"","lastName":"Karabulutoğlu","suffix":""},{"id":571409223,"identity":"439ab572-cb58-4593-b1a4-57de69e56d61","order_by":1,"name":"Lorenzo Casprini","email":"","orcid":"https://orcid.org/0009-0005-9377-5941","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Lorenzo","middleName":"","lastName":"Casprini","suffix":""},{"id":571409224,"identity":"b2b5c825-023f-49fb-832b-db30056d64e8","order_by":2,"name":"Raya Muttarak","email":"","orcid":"https://orcid.org/0000-0003-0627-4451","institution":"University of Bologna","correspondingAuthor":false,"prefix":"","firstName":"Raya","middleName":"","lastName":"Muttarak","suffix":""}],"badges":[],"createdAt":"2025-12-31 08:30:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8487713/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8487713/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":99861032,"identity":"69bda2f3-dafa-45fc-95a8-19462aab04ae","added_by":"auto","created_at":"2026-01-09 07:06:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":4199099,"visible":true,"origin":"","legend":"","description":"","filename":"InternalMigrationItaly.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8487713/v1/30785cefd9c2b9fda178f5b0.pdf"},{"id":99861031,"identity":"7728e07f-5393-46ad-bacd-44468660d46e","added_by":"auto","created_at":"2026-01-09 07:06:03","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":6323,"visible":true,"origin":"","legend":"","description":"","filename":"NCOMMS25105535.json","url":"https://assets-eu.researchsquare.com/files/rs-8487713/v1/24cda2e05057738377427a93.json"},{"id":100357861,"identity":"ad4bc7ac-777d-4ac3-9c4c-18ddb712b98d","added_by":"auto","created_at":"2026-01-16 07:20:27","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2329172,"visible":true,"origin":"","legend":"Article File","description":"","filename":"InternalMigrationItaly.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8487713/v1_covered_8205ea83-7198-4fdb-baaa-c4c582096bc1.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Climate migration in Europe? 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