International Journal of Biometeorology最新文献

{"title":"Non-linear predictive modeling and comprehensive meta-analysis of rectal temperature in Santa Inês sheep: a systematic review of thermal challenges and biometerological trends","authors":"Giulia Correa Sassi,&nbsp;João Flavio de Paulo Costa Santos,&nbsp;Jaqueline de Oliveira Castro,&nbsp;Tadayuki Yanagi Junior","doi":"10.1007/s00484-026-03310-5","DOIUrl":"10.1007/s00484-026-03310-5","url":null,"abstract":"<div><p>A systematic and bibliometric review, combined with a meta-analysis, was used to adjust an equation for estimating the physiological responses of Santa Inês sheep subjected to different thermal challenges. The systematic review compiled data on physiological responses and the thermal environment, which were then used in the meta-analysis to adjust regression models. The bibliometric analysis mapped the relationships among studies, highlighting their usefulness in interpreting research findings and biases. Addressing prior methodological critiques, the core of this study involves replacing the linear approach with a non-linear segmented regression model to accurately define the Thermal Neutral Zone (TNZ). The Segmented Regression Model was crucial, establishing the upper limit of the Thermal Neutral Zone (TNZ) at an air temperature (t_air) of 34.64 °C, where t_rectal begins to increase abruptly. The model, while identifying a biologically significant breakpoint, exhibited a moderate Multiple R-squared of 0.3529, highlighting the high heterogeneity and methodological variability in the current Santa Inês literature. This non-linear approach offers a biologically superior tool for identifying the onset of thermal distress.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00484-026-03310-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148927765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the potential genotoxic/mutagenic effects of peroxide-treatment on organic fractions of thermal–mineral waters","authors":"Csaba Varga","doi":"10.1007/s00484-026-03304-3","DOIUrl":"10.1007/s00484-026-03304-3","url":null,"abstract":"","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13550015/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenophase-specific responses of winter wheat to drought stress: insights from four decades of observations in Shandong, China","authors":"Yuying Ran,&nbsp;Mengquan Wu,&nbsp;Lina Ren,&nbsp;Hao Wu,&nbsp;Lina Zhang,&nbsp;Yijie Tang,&nbsp;Longxing Liu,&nbsp;Wa Li,&nbsp;Gang Chen,&nbsp;Jinyi Lv,&nbsp;Yunjie Chen,&nbsp;XiaoDan Zhang,&nbsp;Shaoqing Liu","doi":"10.1007/s00484-026-03316-z","DOIUrl":"10.1007/s00484-026-03316-z","url":null,"abstract":"<div><p>As a cornerstone of global food security, winter wheat (<i>Triticum aestivum L.</i>) exhibits yield dynamics that are critically dependent on water availability during pivotal phenological stages. Leveraging monthly meteorological data (1980–2022) and ground-based phenological records from Shandong Province, China, this study quantifies drought conditions during essential growth phases using the seasonal-scale Standardized Precipitation Evapotranspiration Index (SPEI-3). By integrating the Theory of Runs with correlation analysis, we characterize the spatiotemporal patterns of drought and assess phenophase-specific responses over the past four decades. Our findings reveal that: (1) Drought intensity during key phenological stages generally weakened from 1980 to 2022, indicating a long-term alleviation of drought stress. Spatially, droughts were more severe and persistent in western and northern regions, relative to shorter, less frequent, and milder events in the south and east. (2) Phenological shifts displayed a clear divergence: the emergence and tillering stages of winter wheat were delayed, whereas the jointing, booting, and maturity stages advanced across most stations. (3) Drought sensitivity varied considerably across developmental phases. Booting, jointing, and maturity exhibited the strongest negative correlations with drought severity (as indicated by SPEI-3), while emergence and tillering showed weak, non-significant positive responses. Based on these findings, we propose a phenophase-specific adaptation framework that emphasizes targeted irrigation at the booting stage, regionally tailored cultivar selection, and flexible sowing management. This study provides new insights into the biometeorological mechanisms linking drought and crop development and offers a transferable foundation for improving climate adaptation in winter wheat systems.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying temperature reduction and expansion range of urban green spaces","authors":"Zi-En Lin,&nbsp;Tzu-Ping Lin","doi":"10.1007/s00484-026-03290-6","DOIUrl":"10.1007/s00484-026-03290-6","url":null,"abstract":"<div><p>This study, grounded in policy promotion and practical land-use planning. The cooling effects of green spaces of different scales and types on surrounding microclimates were first assessed and then simplified into two key metrics. The first metric, Degree of cooling Effect (△T), quantifies the degree of cooling provided by green spaces, expressed as the difference between the reference air temperature at the outer boundary of each green space and the air temperature in its surrounding areas (°C). The second metric, Range of cooling Effect (RE), indicates the distance and extent over which green spaces exert measurable cooling on the surrounding microclimate. Interpolation techniques were subsequently applied to generate air temperature distribution maps, which were validated against results reported in previous studies. Based on these methods, a schematic urban cross-section of cooling effects was developed using Daan Forest Park as a representative case, providing a clear visual representation of the contributions of green spaces to microclimate cooling and supporting policy and practical planning applications. Since the primary analysis focused on park-square-type green spaces, this study further examines the cooling effects of greenways and tree-lined boulevards and explores alternative methods for evaluating the cooling performance of green spaces.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148904876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Health risks and benefits of UV radiation: Assessing exposure times related to vitamin D3 synthesis alongside the potential risk of sunburn in northern mid-latitudes","authors":"Slavica Malinović-Milićević,&nbsp;Gorica Stanojević,&nbsp;Elena Milićević,&nbsp;Milan M. Radovanović,&nbsp;Dragoslav Pavić,&nbsp;Yerlan Kabiyev","doi":"10.1007/s00484-026-03314-1","DOIUrl":"10.1007/s00484-026-03314-1","url":null,"abstract":"<div><p>In this research, the duration of exposure of unprotected skin required for the synthesis of 1000 IU of vitamin D₃ (₁₀₀₀D₃), along with the associated risk of erythema, was examined for Novi Sad (45.33° N, 19.85° E, 84 m asl) and Kopaonik (43.28° N, 20.80° E, 1710 m asl) (Serbia) in the period 2004–2020. A novel model for estimating hourly ultraviolet radiation doses from daily values was proposed. The focus was on data around local noon (10:00 and 15:00 h CET), skin types II and III, and four age groups (0–21, 22–40, 41–59, 60+). The analysis showed that from April to September, most individuals can expose their skin to sunlight enough to produce ₁₀₀₀D₃ without exceeding the erythema threshold. Nevertheless, during February, March, October, and November, most age groups have a greater risk of erythema prior to achieving ₁₀₀₀D₃. However, in the winter months, the exposure required to obtain ₁₀₀₀D₃ frequently exceeds the level at which erythema can develop. Moreover, during January and December, even spending up to five hours in the sun is insufficient for most individuals to reach the ₁₀₀₀D₃. It is also noted that levels of hourly erythema and vitamin D₃ doses are higher in Kopaonik than in Novi Sad, likely due to the higher elevation. Therefore, the exposure time for causing erythema is shorter in Kopaonik. However, due to a smaller body exposure area, the exposure time required to achieve the ₁₀₀₀D₃ is longer in Kopaonik than in Novi Sad, while sub-erythemal vitamin D₃ synthesis windows are very close, except during winter.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148872503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear expansion, spatial diffusion, and climate-driven dynamics of scorpionism in Brazil: a nationwide time-series and DLNM analysis (2007–2025)","authors":"Elania Barros da Silva,&nbsp;José Francisco de Oliveira Júnior,&nbsp;Amaury de Souza,&nbsp;David Mendes,&nbsp;Mônica Dayane Albuquerque Tenório,&nbsp;Luis Felipe Francisco Ferreira da Silva,&nbsp;Kelvy Rosalvo Alencar Cardoso,&nbsp;Sudhir Kumar Singh","doi":"10.1007/s00484-026-03311-4","DOIUrl":"10.1007/s00484-026-03311-4","url":null,"abstract":"<div><p>Scorpionism has emerged as a growing public health concern in Brazil, characterized by increasing incidence and geographic expansion. Despite this trend, studies integrating climatic drivers and advanced time-series modeling remain limited. This study aims to analyze the temporal dynamics, spatial diffusion, and climate–disease relationships of scorpion sting incidence in Brazil using a nationwide dataset from 2007 to 2025. Monthly scorpion sting data from SINAN/DATASUS were combined with high-resolution climatic variables from the TerraClimate dataset. Descriptive statistics, seasonal analysis, and lagged correlation were applied to explore temporal patterns. A distributed lag non-linear model (DLNM) was used to quantify the non-linear and delayed effects of temperature and precipitation on scorpion sting incidence. The results revealed a pronounced non-linear increase in scorpionism, with a structural breakpoint around 2011 indicating accelerated expansion. Seasonal patterns showed higher incidence between September and November. Lag analysis demonstrated that temperature had the strongest association with incidence, peaking at a one-month lag (<i>r</i> ≈ 0.57), while precipitation exhibited weaker but delayed effects. DLNM results confirmed significant non-linear and lag-dependent relationships, with elevated temperatures associated with increased risk at short lag periods. Scorpionism in Brazil is a climate-sensitive and dynamically evolving epidemiological system, driven by the interaction of environmental variability and urban expansion. These findings highlight the need for integrated, climate-informed public health strategies and predictive modeling approaches to mitigate future risk.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13529833/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148863174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term citizen science data reveals climate influences of tropical tree flowering at the regional scale","authors":"Krishna Anujan,&nbsp;Jacob Mardian,&nbsp;Carina Luo,&nbsp;Ramraj Rajakumar,&nbsp;Hana Tasic,&nbsp;Nadia Akseer,&nbsp;Geetha Ramaswami","doi":"10.1007/s00484-026-03291-5","DOIUrl":"10.1007/s00484-026-03291-5","url":null,"abstract":"<div><p>Tropical tree reproductive phenology is sensitive to changing climate, but inter-individual and interannual variability at the regional scale is poorly understood. While large-scale and long-term datasets of environmental variables are available, reproductive phenology needs to be measured in-site, limiting the spatiotemporal scales of the data. We leveraged a unique dataset assembled by SeasonWatch, a citizen-science phenology monitoring programme in India to assess the environmental correlates of flowering in three ubiquitous and economically important tree species - jackfruit, mango and tamarind - in the south-western Indian state of Kerala. We explored (i) seasonal patterns in the flowering of trees (ii) environmental correlates of flowering onset considering only trees with consecutive observations. We used 165,006 phenology observations spread over 19,591 individual trees over 9 years. We first used bootstrapped circular statistics that accounts for observation biases in time to examine consistency in seasonality of flowering status over the whole season, and flowering onset across years and trees. Similar to results from cohort-based tree monitoring, we demonstrate seasonality in flowering status and onset across species, but also report large interannual and inter-individual variability. We then used used generalized linear mixed models with remotely sensed observations (ERA5-LAND) to show that some of the interannual variation in flowering onset across individuals was associated with environmental variables. Soil moisture, minimum temperature and solar radiation had significant associations with the onset of flowering but these effects were heterogeneous across species and habitats across Kerala. Our results become increasingly important in the face of large spatiotemporal change in the climate of this landscape and other tropical regions. We demonstrate the potential and limitations of citizen-science observations in making and testing predictions at scale for predictive climate science in tropical landscapes.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148837474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat stress responses and thermoregulatory dynamics in Murrah buffalo calves assessed by infrared thermography","authors":"Reetu Kumari,&nbsp;Priyambada Kumari,&nbsp;Brijesh Yadav,&nbsp;Shanker Kumar Singh,&nbsp;Vansh Sharma,&nbsp;Manish Tiwari,&nbsp;Saeeda Khanam,&nbsp;Pooja Dawar,&nbsp;Krishna Verma,&nbsp;Arun Kumar Madan","doi":"10.1007/s00484-026-03307-0","DOIUrl":"10.1007/s00484-026-03307-0","url":null,"abstract":"<div><p>The study investigated thermoregulatory dynamics in <i>Murrah</i> buffalo calves under heat stress using infrared thermography. Six calves (8–12 months old; weighing 125 ± 15.35 kg) were exposed in a psychrometric chamber to temperatures of 25, 28, 31, 34, 37, and 40 °C, corresponding to temperature–humidity indices (THIs) ranging from 73 to 90. Each exposure lasted 12 h daily (0600–1800 h) for 10 consecutive days, with animals kept at 25 °C and 65% humidity (THI: 73.49) during the remaining 12 h. On the 10th day, respiratory rate (RR), pulse rate (PR), rectal temperature (RT), feed intake and water intake were recorded and infrared thermography was done to record body surface temperatures (BST) at head, neck, eye, ear, croup, and muzzle besides blood sampling. Significant increases (<i>p</i> &lt; 0.05) in RT, PR, RR, and water intake were first observed at 34 °C, while feed intake declined significantly (<i>p</i> &lt; 0.05) at 34 °C. BSTs increased significantly (<i>p</i> &lt; 0.05) at 28 °C compared to 25 °C and rose progressively thereafter, though values at 28 and 31 °C, and 34 and 37 °C, were similar except at muzzle. An approximate 5 °C rectal-to-surface temperature gradient was associated with effective thermoregulation under cyclic heat stress. Hematological changes included leukocytosis (<i>p</i> &lt; 0.05) at 34 °C, along with lymphocytosis, granulocytopenia (<i>p</i> &lt; 0.05) and elevated plasma cortisol (<i>p</i> &lt; 0.05) at 31 °C. Among anatomical sites, muzzle temperature exhibited strongest correlation with ambient temperature (<i>p</i> &lt; 0.01), while ear and neck temperatures correlated most strongly with RT (<i>p</i> &lt; 0.01). Correlation analysis further revealed that all studied physiological and hematological parameters, except erythrocytic indices and granulocyte percentage, were significantly (<i>p</i> &lt; 0.05) associated with BST at one or more body sites. In conclusion, progressive cyclic heat exposure induced staged thermophysiological adjustments in Murrah buffalo calves, with 31–34 °C representing a transitional range of systemic activation. Maintenance of an approximate 5 °C rectal-to-surface temperature gradient reflected effective thermoregulatory reserve, whereas its narrowing indicated increasing thermal strain. Ear and neck surface temperatures showed strong associations with rectal temperature, supporting their potential as non-invasive indicators of thermal status. Infrared thermography may therefore aid precision-based heat stress monitoring in buffalo.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148838044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Outdoor thermal perception at a beach within a subtropical marine park","authors":"Jiayi Mi,&nbsp;Qiong Li,&nbsp;Peijie Tang,&nbsp;Qi Li,&nbsp;Haotian Wu,&nbsp;Renzhi Wu,&nbsp;Ariane Middel,&nbsp;Andreas Matzarakis","doi":"10.1007/s00484-026-03298-y","DOIUrl":"10.1007/s00484-026-03298-y","url":null,"abstract":"<div><p>Subtropical coastal regions are increasingly important public spaces within urban systems, yet microclimatic conditions and associated thermal outcomes of beaches and coastal areas remain understudied despite growing climate-related heat risks. The field study on Hailing Island, China, combined micrometeorological measurements with thermal perception assessment using thermal indices, including Physiologically Equivalent Temperature (PET), modified PET (mPET), Universal Thermal Climate Index (UTCI), and a human energy budget (EB) approach, to characterize the beach microclimate and evaluate human thermal responses. This study distinguishes between objective thermal stress and individual-reported thermal perception under self-selected exposure. Results showed that the beach surface had high albedo and increased reflected shortwave radiation, thereby intensifying the radiative heat load and contributing to daytime thermal stress. Sea breezes reduced thermal stress under typical sea–land breeze conditions. Tree-covered beach spaces exhibited improved thermal conditions, with denser canopies (e.g., <i>Casuarina equisetifolia</i> L.) providing stronger solar shielding than coconut canopies. Under unshaded beach conditions, air temperature and mean radiant temperature dominated thermal perception, while the influence of air humidity was partly linked to sea-breeze processes. Under tree-shaded conditions, wind speed and mean radiant temperature became the primary drivers. Users demonstrated adaptive behaviors, including preferential use of shaded areas and exposure management in beach zones. Calibrated thermoneutral ranges for beach users were identified as 20.9 to 30.4 °C (PET), 24.7 to 30.7 °C (mPET), 25.8 to 30.8 °C (UTCI), and − 56.1 to 34.8 W m^− 2 (EB). These results provide evidence to support climate-responsive beach design and heat-mitigation strategies in subtropical coastal environments.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148817035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A fourteen-year analysis of thermal stress in Kuwait","authors":"Ali Al-Hemoud,&nbsp;Hassan Al-Dashti,&nbsp;Ahmad Al-Khayat,&nbsp;Weam Behbehani,&nbsp;Bashayer Almaraghi,&nbsp;Jason Glaser,&nbsp;Petros Koutrakis,&nbsp;Barrak Alahmad","doi":"10.1007/s00484-026-03303-4","DOIUrl":"10.1007/s00484-026-03303-4","url":null,"abstract":"<div><p>The Arabian Peninsula region, particularly the Gulf Cooperative Countries (GCC) experience extreme heat with a warming trend and frequent and intense heat waves. Summer maximum temperatures (June, July, and August ‘JJA’) routinely soar above 50 °C. In this study, we analyzed the heat index (HI) for every hour of the last 14 years (2012–2025) in Kuwait. Heat Index is the combined metric incorporating ambient air temperature and relative humidity (RH) – or the ‘‘feels like’’ temperature. Specifically, we used the US National Weather Service (NWS) HI and classified three risk-threshold systems: HI classified according to Kuwait Oil Company “KOC thresholds”, HI classified according to Saudi Arabia Aramco “Aramco thresholds”, and HI classified according to the NWS “NWS thresholds”. We divided hours and days into four HI category ranges (Extreme Danger, Danger, Extreme Caution, and Caution). Results show a positive linear trend for the annual minimum, average, and maximum temperature and RH during the study period. The mean annual numbers of days of ‘Maximum’ HI levels in the ‘Danger’ category were (119.71 (32%), 96.78 (26.51%), 101.64 (27.84%)) for KOC, Aramco, and NWS thresholds, respectively. The total annual number of days of ‘Maximum’ HI levels exceeded the ‘Extreme Danger’ category for KOC (≥ 46 °C), Aramco (≥ 52 °C), and NWS (≥ 54 °C) by 282 days (77%), 29 (7.9%), and 5 days (1.36%), respectively. The year 2025 demonstrated the highest number of days on which daily maximum HI exceeded the ‘Extreme Danger’, particularly in August. A total of 17 h exceeded the NWS threshold (≥ 54 °C), and the hours ranged from as early as 9 am to 4 pm. Moreover, HI as high as 52 °C was observed, in some instances, as early as 7 am and as late as 7 pm and midnight. This study provides a basis for heat stress extremities in hot arid environments, especially in the era of climate change. Temporal variability in thermal stress is essential to understand for both public and occupational health.</p></div>","PeriodicalId":588,"journal":{"name":"International Journal of Biometeorology","volume":"70 9","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}