Spatiotemporal Characteristics of Heatwave in the Central Region of Bangladesh

Spatiotemporal Characteristics of Heatwave in the Central Region of Bangladesh | 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 Spatiotemporal Characteristics of Heatwave in the Central Region of Bangladesh Humaira Rahman Logna, Md Anarul Haque Mondol, Sworna Akter, Hafizur Rahman, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7496532/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 Bangladesh, being one of the countries vulnerable to climate change, is also susceptible to heatwave and heat stress alike. This study aims for a comprehensive assessment of the spatiotemporal characteristics of heatwaves in the central region of Bangladesh from 1981 to 2020, based on historical climatic data. Calculated heat indices, using the formula of apparent temperature, characterize heatwave, and categorized into severity-based thresholds based on the National Weather Service (NWS) definition of heatwave, modified accordingly to reflect local climatic variations. Along with the broad spatial distribution of heatwave, this study also explores the seasonal variation of heatwaves through trend analysis and the potential seasonal shifts in the region. Also, evaluating the frequency of severe and extreme heat days through the coefficient of determination and regression analysis provides quantitative insight into predicting future risks. Spatially, in Tangail, Faridpur, and Madaripur, the heatwave events have amplified mainly after the 1990s, while Madaripur exhibits the earliest onset, and Dhaka, in contrast, shows a delay. Summer and monsoon have emerged as the seasons experiencing the most heatwaves throughout the region. The findings also reveal statistically significant intensification patterns in the overall frequency of heat days across the region. The annual severe heat days in regions like Tangail, Faridpur, and Madaripur have been shifting toward extreme heat days in the last decade, with severe days showing a downward trend and extreme days increasing. In contrast, the number of extreme heat days is rising continuously in Dhaka. This pattern reveals a potential risk for the future, suggesting a regionalized approach to deal with the growing heatwave. Both academics and policymakers can benefit from the localized insights this study offers into the features of heatwaves. Future studies should cover a larger geographic area and include a more thorough set of socioeconomic indicators in order to improve the understanding of heatwave risks on a national level. Heat index spatiotemporal characteristics extreme heat air temperature climate change seasonal variation humidity Bangladesh Full Text Additional Declarations No competing interests reported. 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. 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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-7496532","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":526661145,"identity":"2074e390-f58c-4356-956d-120e851191cf","order_by":0,"name":"Humaira Rahman Logna","email":"","orcid":"","institution":"Jahangirnagar University","correspondingAuthor":false,"prefix":"","firstName":"Humaira","middleName":"Rahman","lastName":"Logna","suffix":""},{"id":526661146,"identity":"941894d8-0225-4c86-b620-2ac08c1581eb","order_by":1,"name":"Md Anarul Haque 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This study aims for a comprehensive assessment of the spatiotemporal characteristics of heatwaves in the central region of Bangladesh from 1981 to 2020, based on historical climatic data. Calculated heat indices, using the formula of apparent temperature, characterize heatwave, and categorized into severity-based thresholds based on the National Weather Service (NWS) definition of heatwave, modified accordingly to reflect local climatic variations. Along with the broad spatial distribution of heatwave, this study also explores the seasonal variation of heatwaves through trend analysis and the potential seasonal shifts in the region. Also, evaluating the frequency of severe and extreme heat days through the coefficient of determination and regression analysis provides quantitative insight into predicting future risks. 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