Physiologically Equivalent Temperature Values Research Articles

Effect of the spatial form of Jiangnan traditional villages on microclimate and human comfort

The spatial form of a village can affect human comfort by changing microclimatic conditions, which in turn can affect the health of residents. The architectural forms of traditional Jiangnan villages have been adapted to local environmental and landscape characteristics, creating optimal thermal comfort conditions. However, these traditional forms are being lost in China's rapid drive toward urbanization and modernization, resulting in built environments that offer far less thermal comfort. To explore the elements of traditional adaptation, we conducted microclimate research in Shecun Village, Nanjing, and examined how the form of the surrounding landscape influenced the spatial layout of village streets and public spaces. Air temperature, relative humidity, and average wind speed were measured at locations around the village and were compared to similar data collected from a meteorological station in urban Nanjing. Based on these data, ENVI-met software was used to create a numerical simulation to demonstrate the relationship between the spatial forms of traditional Jiangnan villages and local microclimate factors. We found that the average physiological equivalent temperature (PET) values of all measurement points in the village in the summer were between 42°C and 48°C, and those in the winter were between 17°C and 20°C. In general, the thermal comfort in the winter was better than that in the summer, and the overall middle-level climate environment of the village in the winter and summer was comfortable. The PET values at different points followed the order of building complex space (MP1, 3 and 5) > vegetation space (MP2) > water space (MP4). The PET value was positively correlated with comfort sensation in winter, but this value had the opposite correlation in the summer. The average value of PET at the vegetation space was 3.18°C higher than that at the water space in the winter, which showed that the water body was beneficial for thermal comfort in the summer, but was the opposite in the winter. These results showed that the traditional village site selection in accordance with local conditions, made use of the surrounding landscape environment to provide villages with a more comfortable and pleasant living environment. This information provides a useful reference for the design of modern public spaces.

Investigation of the thermal environment in schoolyards under Mediterranean conditions. Contribution to bioclimatic conditions improvement with the application of mild interventions – The case study of a school within the urban environment

This study aimed to examine the thermal environment in schoolyards under Mediterranean conditions, and the impact of two interventions on the amelioration on the bioclimatic conditions.The investigation was performed for three schools in Athens, Greece, through microclimatic simulations by ENVI-met, for a typical day in June, and was evaluated based on the air and surface temperature values. The bioclimatic index Physiological Equivalent Temperature (PET) was applied to evaluate the thermal comfort conditions.By that, the school under the most adverse thermal conditions was selected for the application of two interventions, which increased the greenery by 25% (Proposal 1) and 50% (Proposal 2). The surface coating material “safety floor slabs”, was selected to replace the others in both proposals.Through microclimatic simulations, the following results were obtained: “Proposal 1” caused a 2.3°C reduction in surface temperature, and a 4% reduction in PET values. ‘Proposal 2’ caused an 8.1°C reduction in surface temperature, and an 11% reduction in PET values. The cooling effect of ‘Proposal 2’ was double compared to ‘Proposal 1’, achieving a maximum air temperature reduction by up to 0.8°C. The cooling effect produced was limited to the areas affected by tree shade, leaving the unshaded areas almost unaffected.

Evaluation of the Effects of Thermal Comfort Conditions on Cardiovascular Diseases in Amasya City, Turkey.

Studies fall short when it comes to determining the relationship between thermal comfort and cardiovascular diseases. Studies examining the relationship between thermal comfort conditions and human health in Turkey, located in the transition zone of air masses at mid-latitudes, are quite limited. This is the first study conducted in Turkey that deals with thermal comfort conditions and CVDs, which is the leading cause of death. This study aimed to examine the relationship between thermal comfort conditions and CVDs of Amasya, a medium-sized exemplary Turkish city. To determine the thermal comfort conditions in the study area between 2014-2019, the physiologically equivalent temperature (PET) index obtained from the Rayman model, which uses hourly air temperature (ºC), relative humidity (%), wind speed (m/s), and cloud cover (octa) data, was used. The relationship between PET values and CVDs was determined by Pearson correlation analysis and linear regression analysis. The study indicated a negative, high, and moderate correlation between PET values and cardiovascular diseases (p < 0.001). The results show that when PET values increase by 1 ºC, patient admissions will decrease by about 104 to 108 patients (-104.737 to -108.619 units.). These results can be informative and guiding for both the protection of public health and studies on climate change and human health.

Effects of Tree Species and Layout on the Outdoor Thermal Environment of Squares in Hot-Humid Areas of China

Planting trees is an effective way to regulate the outdoor thermal environment and combat urban heat islands (UHIs). Tree species and layout can have a considerable effect on, for example, the outdoor shading and wind fields, and finally the distribution of the occupant thermal sensations in outdoor spaces. We studied the influence of common tree species and layouts on the outdoor thermal environment under typical summer and winter weather conditions in the hot–humid areas of China. Each arbor model was established by the physical parameters obtained from field measurements. Physiological equivalent temperature (PET) was used to evaluate the thermal performance of the outdoor environment. The ENVI-met software was validated with field measurements and then used to assess the outdoor thermal environment under typical summer and winter weather conditions. The results showed the following: (1) Without considering the tree species, the difference in maximum PET values for different planting distances in summer and winter was 1.14 and 2.13 °C, respectively. (2) Planting arbors with different planting methods in inactive spaces had little effect on the thermal environment of the surrounding active space. (3) Arbors with high leaf area density (LAD) values performed better in regulating outdoor thermal comfort than arbors with low LAD values. The maximum differences in PET values of different arbors in summer and winter were 0.98 and 1.37 °C, respectively. This study provides practical suggestions for arbor planting in square spaces in the hot–humid areas of China.

Assessment of outdoor shading strategies to improve outdoor thermal comfort in school courtyards in hot and arid climates

• To encourage students to perform different activities and interact in open spaces of school • to improve OTC for students in school courtyards located in a hot, arid climate. • Significant reduction in the PET for courtyard temperatures based on the ENVI-met model reached 18.5°C • To integrate hybrid scenarios of staggered shading and trees whether in the current schools or in the early design stages Schools in hot arid climate depend on courtyard to encourage students’ for social activity. In order to improve Outdoor Thermal Comfort (OTC), applying passive mitigation strategies in the courtyard is critical issue. This paper aims to improve students’ thermal comfort in school courtyards throughout the study of a public school with an E-shaped style in New Assiut City. Hence, different shading strategies (shading with different heights, vegetation, and hybrid) are simulated by using ENVI-met model v 5.0.0 to improve OTC for students in school courtyards. Firstly, monitoring was conducted inside outer courtyards. Then nine scenarios of passive strategies were implemented inside two courtyards with a ratio H/W = 0.4 and 0.7. After that, Physiological Equivalent Temperature (PET) was used to compare different scenarios. The results found, by applying hybrid orthogonal and diagonal staggered shading with trees in wide canyons, significant reductions of PET values reached 18.5°C and 18.6°C respectively. In addition, the shading at height= 4 m hybrid with trees achieves the best OTC improvement in the school courtyards. Thus, PET values were located in comfortable and slightly warm ranges for wide courtyard with H/W ratio = 0.4, and this result is more sufficient than in deep canyon with H/W = 0.7. Hence, the study provides information for architects and planners to integrate hybrid scenarios of staggered shading and trees whether in the current schools or in the early design stages for them to reduce heat stress and improve students’ thermal comfort.

Field Survey on Local Thermal Comfort of Students at a University Campus: A Case Study in Shanghai

University campuses have various functional outdoor spaces characterized by diversified spatial morphology. This study focuses on the local thermal environment of a university campus by conducting fixed weather station monitoring and a mobile survey on a typical summer day. Questionnaire results of college students accompanied by the surrounding climatic conditions reveal obvious linear relationships between thermal sensation voting (TSV) and thermal index physiological equivalent temperature (PET). The range from 29.16 °C to 32.04 °C of the PET is discussed as evaluating the thermal neutral sensation. The PET variations at nine test sites are different due to their different surrounding environments. Mobile survey results across the whole university campus emphasize that the PET varied with time and space in local zones. Spatial differences in the thermal environment are small at 9:00 and larger at 14:00. A correlation analysis of the local Ta and relative humidity (RH) reveals the different effects of spatial morphology characteristic parameters. After calculating the averaged PET values of local zones, problem zones with a higher PET exceeding the thermal neutral limit are recognized. Appropriate optimization on the geometry layouts and land cover patterns is proposed, which would help guide environmentally comfortable university campus design.

Sensitivity of Different Physics Schemes in the Simulation of Heat Wave Events over Bangladesh Using WRF-ARW Model

Heat waves (HWs) are an extreme temperature condition that has a direct impact on human lives. In recent years, a large number ofpeople have died all over the world due to hot weather. The purpose of this study is to predict HWs accurately to mitigate the casualtiescaused by them. Two HW events are selected for this study (Event-1: 0000 UTC of 18 May to 0000 UTC of 25 May 2015, Event-2:0000 UTC of 05 April to 2100 UTC of 08 April 2015). At first, sensitivity tests have been done using different combinations ofphysics schemes. Sensitivity of Planetary boundary layer (PBL) and surface layer (SL) schemes combinations (YSU-Revised MM5,YSU-MM5, MYJ-Eta, and ACM2-Revised MM5) and land surface models (RUC, Noah, Noah-MP, and CLM4) are investigated topredict Comfort Index (CI), which is identified by using Physiological Equivalent Temperature (PET). To simulate PET, the primarymeteorological variables 2-m air temperature (T2), 2-m relative humidity (rh2), mean radiant temperature (TMRT), wind speed at 10m (ws10), and cloud cover data have been used. These parameters were simulated by the WRF model using both single and nesteddomains. The experiments found that the combination of the YSU-MM5 scheme and the Noah land surface model predicted theWRF simulated variables very well. The study also found that the CI exists between the slight heat stress to extreme heat stress andthe maximum PET values were found to be 47.6 ºC and 48.5 ºC for Rajshahi and Khulna event respectively.&#x0D; Dhaka Univ. J. Sci. 70(1): 70-78, 2022 (January)

Impacts of Water Bodies on Microclimates and Outdoor Thermal Comfort: Implications for Sustainable Rural Revitalization

Water is the source of life and the fundamental element of ecology, and climate is inseparable from water. To evaluate the influence of water-adaptive space in a traditional Weizi (polder village) settlement on its microclimate, the authors analyzed the morphological characteristics of such a polder village and applied the ENVI-met model to simulate the impact of water bodies and village morphological elements on human thermal comfort. This paper demonstrates the positive impact of water bodies on improving the thermal environment of a village and regulating its microclimate by quantifying the impact of morphological elements of the settlement on microclimate. The results indicate that: 1) The simulation model fits the actual measurements well, and the simulation accurately reflects experimental results; 2) In summer, the cooling effect of water bodies is better in the afternoon than in the morning, especially from 12:00 to 15:00. The cooling effect is significantly correlated with the distance to water bodies, i.e., the closer, the better; 3) Building density and man-made underlying surface are negatively correlated with temperature, humidity, and Physiological Equivalent Temperature value, while greening rate and water body rate are positively correlated with microclimate. Overall, water bodies can improve outdoor comfort in summer and thus should be protected and developed in rural planning and design. Villages can be built around water bodies for a maximized cooling effect, and microclimate comfort can be effectively improved by increasing green plants near the village center, and reducing man-made underlying surface and building density. The results of this study will guide the improvement of the habitat environment in the process of rural revitalization, as well as the protection and re-development of traditional villages.

The Impact of Vegetation Arrangement on Outdoor Thermal Comfort: A Simulation Study in a Tropical Urban Public Square

Thermally comfortable urban squares attract people and provide various social benefits to the urbanites. Compared to urban parks, squares are more vulnerable to thermal discomfort due to surrounding buildings and the high percentage of hard surface coverage, especially in tropical climates. The spatial arrangement of green infrastructures can improve Outdoor Thermal Comfort (OTC) by reducing hot air flows, evapotranspiration, and shading to reduce the negative effect of warming urban environments. However, it is not yet adequately discovered the specific correlation of different vegetation arrangements on OTC. Still, urban policymakers are looking for new, quantitative methods to assess the performance of their designs in terms of the cooling effects provided by vegetation. Therefore, the current study investigates the effect of different vegetation arrangements on OTC in a tropical urban public square (Independence Arcade in Colombo) using micrometeorological fluid dynamics (CFD) modeling validated by field measurements. Air temperature (Ta), relative humidity (RH), wind speed (WS), and wind direction (WD) were measured at 1.5 m above ground level as the inputs for the ENVI-met simulation model to assess the cooling performance of proposed scenarios employing Physiological equivalent temperature (PET). Nine scenarios were developed using trees with high leaf area density (LAD) and spherical canopy form to compare OTC improvements of cluster, random and individual planting patterns, and the size of trees (large, medium, small). The results showed that vegetation improves the OTC levels irrespective of the planting pattern. However, linear individual planting pattern with large trees performed the best cooling performance, and scenarios were ranked according to improved PET values. Vegetation parameters are recommended to arrange in different ways to achieve OTC and aesthetics. The study was limited to the existing vegetation database of the ENVI-met software package, but further research could consider the context-specific tree species and the impact of combined landscape scenarios using grass, shrub coverage, and water bodies to find proper arrangements to improve the microclimate and OTC. This study guides urban planners and landscape architects to assess the cooling performance of the proposed designs and arrange urban vegetation to create thermally comfortable urban outdoors in the tropics. &#x0D; Keywords: Vegetation arrangement, Urban square, Outdoor thermal comfort, ENVI-met, PET&#x0D; Acknowledgement: Authors acknowledge the assistance of the Accelerating Higher Education Expansion and Development (AHEAD)-DOR Grant, funded by the World Bank

How Tmrt Affects PET Assessment in Outdoor Environments: A Comparative Study

Many studies have explored outdoor thermal comfort during the last several years, ever since it has been strongly related to human health and well-being. The physiological equivalent temperature (PET) is one of the most commonly used thermal comfort indexes. It has been approved and applied within different urban spaces and climates. This study is a comparative research that explored the importance of using mean radiant temperature (Tmrt) in PET assessment by employing two different methods. The first method was used to calculate PET based on three measured variables including relative humidity, wind velocity, and air temperature. RayMan software was utilized to perform the calculations. The second method was used to calculate PET by combining Envi-met and RayMan. Envi-met allowed four sets of calibrated data, including the data of air temperature (Ta), wind velocity (Wv), relative humidity (RH), and mean radiant temperature (Tmrt). RayMan software used the calibrated results to calculate PET. These methods were explored in outdoor environments at Annaba, Algeria, characterized by a Mediterranean climate. The results showed significant differences in PET values, especially through the warmest times of the day. The first method highlighted very high PET values, where 40 ≤PET&lt;51 at noon. At the same time, using Tmrt gave precise PET values (30≤PET ≤32). Based on these findings, we can confirm the importance of considering Tmrt in PET calculation, which allows one to identify the accurate comfort range.&#x0D; Keywords: Algeria, Mean Radiant Temperature (Tmrt), mediterranean climate, Physiological Equivalent Temperature (PET), thermal comfort

Thermal Comfort-Based Spatial Planning Model in Jakarta Transit-Oriented Development (TOD)

Transit-oriented development (TOD) is integrated spatial planning and transportation that enhances walkability and other green mobility. The issue of thermal comfort in walkability is a major concern in the TOD of cities in tropical climates such as Jakarta. This study aimed to model and compare microclimate conditions and thermal comfort between existing conditions and TOD spatial planning scenarios. The microclimate condition was modeled using ENVI-met, and thermal comfort was analyzed following the physiologically equivalent temperature (PET) and universal thermal comfort index (UTCI). The results of microclimate modeling showed that the average minimum temperature of the current condition was lower than the TOD at 0.149 °C; meanwhile, the average maximum temperature of the current condition was higher than the TOD at 0.761 °C. Furthermore, the results of the PET and UTCI calculation between the existing land use and the TOD plan scenario showed that both the minimum and maximum PET and UTCI values of the TOD plan scenario throughout the modeling time were lower than the existing conditions. In conclusion, the urban canyon formed by the designed TOD scenario resulted in lower wind speed than the existing condition. However, this factor potentially does not impact the increase in the urban heat island effect in the TOD area since the effect of shading the area by the high-rise building lowers the temperature.

Future impact of cloudiness and wind changes on thermal comfort conditions in the city of Tabriz (Iran) in the frame of climate change

• Cooling effect of the wind will decrease with time in Tabriz. • Thermal comfort must be incorporated in urban planning strategies. • Changes in cloudiness is a key factor for thermal comfort in Tabriz. Climate change will alter thermal comfort very differently depending on the future scenario selected. This research computes two bioclimatic indices: Physiological Equivalent Temperature (PET) and Universal Thermal Comfort Index (UTCI), in the area of Tabriz (Iran), considering an observational period (1960 to 2020) and three projected scenarios (RCP2.6, RCP4.5, and RCP8.5) associated to greenhouse gas concentrations for the period 2030 to 2059 and 2060 to 2100. The CanESM2 model was used to estimate projected data. Thermal comfort for these three periods are compared at daily basis attending to the sky conditions (clear and cloudy) and the presence or absence of wind. The study of the observational period shows that the cloud cover effect has increased PET and UTCI values by 0.82 and 0.51°C, respectively. For the projected period, it has been found an increase in PET and UTCI values by 0.36 and 0.42°C associated to the presence of clouds. On the other hand, a decrease in temperature of 10°C for PET and 11.73°C for UTCI is found in the observational period when windy and calm days are compared. This cooling effect of the wind will decrease in the projected period where temperature reduction based on PET and UTCI values is estimated to be 4.5 and 8.4°C for 2030-2059 and 2.5 and 5.2°C for 2060-2100 respectively. In conclusion, future changes in clouds and wind will clearly impact thermal comfort in the city of Tabriz in the future decades. Both the projected cloudy heating effect and the reduction of the potential of cooling of the wind, will have serious implications for heat-related diseases and different socioeconomic activities in the region. Accordingly, the definition of mitigation and adaptation strategies in short term should be a priority.

Biometeorological Conditions during the August 2015 Mega-Heat Wave and the Summer 2010 Mega-Heat Wave in Ukraine

The human-biometeorological conditions in Ukraine during two mega-heat waves were analyzed. The evaluation is based on physiologically equivalent temperature (PET). The calculation of PET is performed utilizing the RayMan model. The results revealed these two mega-heat waves produced strenuous human-biometeorological conditions on the territory of Ukraine. During the summer 2010 mega-heat wave, strong and extreme heat stress prevailed at about midday at the stations where this atmospheric phenomenon was observed. The mega-heat wave of August 2015 was characterized by a lower heat load. The diurnal variation of PET values during the researched mega-HW was similar to that of the diurnal variation of air temperature with minimum values in the early morning and maximum values in the afternoon. On the territory where mega-heat waves were observed, the number of days during which heat stress occurred for 9 h amounted to 97.6% for the period from 31 July to 12 August 2010 and 77.1% for the mega-heat wave of August 2015.

An Investigation on the Thermal Environment of Residential Courtyards in the Cold Area of Western Sichuan Plateau

Located on the east side of China’s Qinghai–Tibet Plateau is the Western Sichuan Plateau, the courtyard adopts a passive design to withstand the harsh climate in cold areas, and its internal thermal environment has a direct impact on the productivity and activities of the residents. This paper takes a plateau village (3500 m above sea level) beside the Sichuan–Tibet line as the research area, and selects four typical local courtyard layouts and an outdoor reference point for the measurement and comparison of the thermal environment. By comparing the measured parameters inside and outside the courtyard, and the correlation analysis, it was deduced as follows. (1) In the cold winter, traditional plateau residential courtyards can create a stable internal micro-climate, but the cold resistance of the courtyards is closely related to its layout. (2) Except for wind speed, other thermal environment parameters of the courtyard are all affected by solar radiation (3) The correlation analysis of the various environmental parameters and physiologically equivalent temperature (PET) showed that the correlation coefficient between the mean radiation temperature (Tmrt) and all courtyard PET values is &lt;0.0001, showing a significant correlation. The indicators of mean temperature radiation are mainly affected by the temperature and the wind speed; furthermore, the temperature and solar radiation are positively correlated, which confirms that the solar radiation and wind speed within the courtyard are the main factors affecting the internal thermal environment in the courtyard. (4) Feedback the courtyard layout problems through the difference in the thermal environment parameters within different courtyards, and then determine some shortcomings in the current courtyard layout design. The inferences drawn from this work will provide a scientific basis for the design, layout, and construction of courtyards in other cold plateau areas.

The predicted effectiveness of thermal condition mitigation strategies for a climate-resilient archaeological park

The study aims to predict the effectiveness of three mitigation strategies in improving the thermal comfort of the visitor area at the Prambanan Temple Tourism Park formulated in the previous research, namely: cooling effects of a park surrounding the visitor area, cool transparent coating on the temple stones, and the placement of potted tree clusters (green parasols) based on strolling comfort distance. This study used validated ENVI-met microclimate models to predict the effectiveness measured by reducing the mean Physiologically Equivalent Temperature (PET) value in the visitor area on the hottest day and during hottest hours caused by the implementation of each strategy. The simulation results show the role of shading created by green parasols in decreasing the PET value in the visitor area, i.e. 2.53 °C. Meanwhile, The PET values decrease by 1.75 °C due to the cool transparent coating and only by 0.23 °C due to the park surrounding the visitor area. The most significant reduction in the PET value by the park with 5 m high trees and a sparse grid layout compared to 10 park variants is found more related to the layout density.

Factors influencing resident and tourist outdoor thermal comfort: A comparative study in China's cold region

Thermal comfort and environmental health in scenic open spaces, a communication bridge between tourists and their environment, are prerequisites for tourism activities. In this study, scenic open spaces in an urban area of Xi'an, China were selected. Thermal perception (thermal sensation, comfort and acceptability) of residents and tourists were investigated through meteorological measurement and questionnaire survey. Physiological equivalent temperature (PET) was used to determine thermal benchmarks of all visitors to the site. Variables that influence individual thermal perception assessment (physical, individual, society and psychology) were measured and compared. Finally, a series of strategies and suggestions were proposed based on meteorological characteristics and influencing factors of thermal perception from perspectives of designers and scenic spot managers. Results show that: 1) Neutral PET (NPET) of respondents were 17.3 °C (residents) and 15.5 °C (tourists). Neutral PET ranges (NPETR) were 8.9–25.8 °C (residents) and 7.2–23.8 °C (tourists). Preferred PET values were 20.1 °C (residents) and 19.7 °C (tourists). Thermal acceptability ranges (TAR) were 6.3–37.8 °C (residents) and 0.5–39.9 °C (tourists). 2) In winter, physical factors were primary influencers of residents' thermal perception, followed by social factors, while tourists' thermal perception was mainly influenced by physical factors. In spring, physical factors were still the primary influencers for residents, followed by individual factors. Physical factors were also dominant for tourists, followed by psychological. In summer, physical factors were the major influencing factors for residents and tourists' thermal perceptions.

Thermal comfort analysis through development of artificial neural network models: An experimental study in Cwa climate

This work presents the development of artificial neural network (ANN) models to predict outdoor thermal comfort using the Physiological Equivalent Temperature (PET) index for a college campus in Cwa climate (dry winter humid subtropical climate as per Köppen Climate Classification). Thermal modeling of the study area is exercised using ENVI-met. Twelve different ANN models were developed and tested to evaluate the effectiveness of ANN in predicting the thermal comfort index for the summer and winter months. Two network models were developed using all major meteorological variables. Ten network models were developed using only air temperature, relative humidity, solar radiation, mean radiant temperature, and wind speed respectively. ANN models with all major meteorological variables proved to be effective in estimating close PET values for both summer (R2 = 0.99) and winter (R2 = 0.99). For cases when only one variable is available, network models featuring only air temperature proved effective for both summer (R2 = 0.93) and winter (R2 = 0.92).

Physiological Equivalent Temperature (PET) index and cardiovascular hospital admissions in Ahvaz, southwest of Iran

Evidence shows that climate change may have adverse effects on human health. The purpose of this study was to investigate the relation between Physiologically Equivalent Temperature (PET) and cardiovascular hospital admissions in Ahvaz. Distributed Lag Non-linear Models (DLNM) combined with quasi-Poisson regression models were used to investigate the effect of PET on hospital admissions. Low PET values (6.4 °C, 9.9 °C and 16.9 °C) in all lags, except lag 0-30, significantly decreased the risk of hospital admissions for total cardiovascular diseases, hypertension, ischemic heart diseases, and cardiovascular admissions in men, women and ≤65 years. But, low PET (6.4 °C) in lags 0 and 0-2 significantly increased the risk of hospital admissions for cerebrovascular diseases; and high PET values increased the risk of ischemic heart diseases and in men. Both cold and hot stress are involved in cardiovascular hospital admissions.

Assessing the influence of street configurations on human thermal conditions in open balconies in the Mediterranean climate

Heat stress in the built environment has become a serious health and comfort issue, given the increases in Urban Heat Island effects, and augmenting impacts associated to climate change. This study deals with the potential correlations between human thermal conditions, the encircling microclimate, and the physical structure of the city. Through long-term numerical simulations, the disclosed study analyses the influence of the urban street configurations on the thermal bioclimate within urban canyons, specifically upon open balconies in the most populated district of Barcelona: The Eixample. The simulated thermal conditions were carried out in the human biometeorological RayMan Pro model using local climatic data, to determine the Physiologically Equivalent Temperature (PET) within four generated scenarios, with similar morphological properties of the Eixample district.The findings reveal that streets with axes oriented NS and SE-NW provide the best thermal conditions for balconies, achieving acceptable PET values (18 °C < PET <29 °C) on both façades. On the other hand, EW streets presented high thermal stress conditions (over 43,4% of the time) for those balconies located in the north side of the canyon. Open balconies at heights below 12 metres are the most comfortable ones during summer daytime, with acceptable thermal conditions that range between 50,4% and 82,5% of the time. The highest frequencies of acceptable thermal conditions were found on balconies located at 6 metres and 9 metres high on the east, south and southeast façades of the NS, EW and NE-SW oriented streets respectively (from 77% to 83% of the time). These configurations provide the most suitable thermal conditions during the studied summer periods by having frequencies of heat stress below 20%.Our results and recommendations contribute to bridge the gap between human biometeorology, public health, and architectural and urban planning. Some areas of its direct application are the use of balconies in periods of confinement; decision-making on the sale or rental of apartments; and the promotion of bioclimatic retrofit projects at an urban and architectural scale supported by local governments.

Physiological equivalent temperature (PET) and non-accidental, cardiovascular and respiratory disease mortality in Ahvaz, Iran.

Climate change may be associated with human morbidity and mortality through direct and indirect effects. Ahvaz is one of the hottest cities in the world. The aim of this study was to investigate the relation between physiological Equivalent Temperature (PET) and non-accidental, cardiovascular and respiratory disease mortality in Ahvaz, Iran. Distributed Lag Non-linear Models (DLNM) combined with quasi-Poisson regression were used to investigate the effect of PET on death. The effect of time trend, air pollutants (NO2, SO2 and PM10), and weekdays were adjusted.The results showed that in cold stress [1st percentile of PET (2.7°C) relative to 25th percentile (11.9°C)] the risk of total respiratory mortality, respiratory mortality in men, and mortality in people under 65year olds, significantly decreased in the cumulative lags of 0-2, 0-6 and 0-13; but the risk of respiratory mortality increased in the elderly and in the final lags. In contrast, heat stress [99th percentile of PET (44.9°C) relative to 75th percentile (43.4°C)] significantly increased the risk of total cardiovascular mortality (CVD), cardiovascular mortality in men, ischemic heart disease and cerebrovascular disease mortality in lags 0 and 0-2. It seems that high PET values increase the risk of cardiovascular mortality, while low PET values increase respiratory mortality only among the elderly in Ahvaz.