Summer thermal comfort in Czech cities: measured effects of blue and green features in city centres

Impact of heat waves on semen quality: A retrospective study in Argentina between 2005 and 2023

Heat waves, defined as periods with daily temperatures surpassing the historical average for a specific region, have become more frequent worldwide in recent years. Previous studies have reported a negative association between temperature and semen quality, but the focus has mainly been on Asian and European populations. The study included 54,926 men (18-60 years) undergoing routine semen analysis between 2005 and 2023 at CEUSA-LAEH andrology unit, in Buenos Aires, Argentina. Hourly temperature readings were provided by the Servicio Meteorológico Nacional. R programming (R Studio v2022.07.2) was used to define heat waves, calculate key characteristics, visualize results, and perform statistical tests at the IBYME laboratory. During the period studied, a total of 124 days had heat waves (defined after at least 3 consecutive days with 32.3 °C and 22 °C). Men exposed to heat waves during spermatogenesis exhibited lower sperm number (concentration and count; P < 0.0001) and decreased normal morphology (percentage of normal sperm and normal motile count; P < 0.05) compared to those not exposed. These differences were most pronounced between semen samples from years with several heat waves (2013, 2023) and none (2005, 2007, 2016), displaying 4-5 times higher fold changes (P < 0.05). Further analysis employing multiple regression revealed a significantly negative association between semen quality and heat wave length, suggesting that a prolonged exposure may be more detrimental than an acute exposure. Subsequent analysis focusing on prolonged exposure (≥6-days heat wave) during spermatogenesis revealed a negative (P < 0.05) association between early exposure (spermatocytogenesis: 64-90 days prior semen collection) and semen quality. This study underscores the negative association between early exposure to heat waves during sperm development and semen quality, raising concerns about its possible association with the worldwide declining male fertility. A comprehensive collaborative approach is crucial, involving global governmental policies, sustainable practices, and coordinated efforts across scientific, healthcare, and policy domains.

Future climate suitability of Hemileia vastatrix in arabica coffee under CMIP6 scenarios

BACKGROUND

Coffee (Coffea arabica L.) is one of the most important commodities today, with a high economic value worldwide. Coffee leaf rust (Hemileia vastatrix Berk. et Br.) has been showing a high impact on Brazilian coffee trees among the various diseases that attack coffee. The climate has a great influence on the development of diseases, especially when fungi are the causal agents. This study aimed to carry out the zoning of climate favorability for coffee leaf rust in the traditional and main coffee-producing regions of Brazil. The study was conducted in 13 locations in the states of Paraná, São Paulo, Rio de Janeiro, Espírito Santo, Minas Gerais, Goiás and Bahia. Air temperature and daily precipitation data for the current scenario were collected using the WorldClim version 2.1 platform for the last climatological normal and future climate change data. The ideal climate conditions for coffee leaf rust consist of a mean air temperature ranging from 21 to 25 °C and precipitation >30 mm per month. The Coupled Model Intercomparison Projects scenarios associated with the Intergovernmental Panel on Climate Change reports consisted of the Shared Socio-Economic Pathways SSP-1 2.6, SSP-2 4.5, SSP-3 7.0 and SSP-5 8.5, the latter being considered one of the most catastrophic. All steps to carry out the suitability zoning were performed in a tool using the QGIS geographic information system software.

RESULTS

Zoning for coffee leaf rust had three classes: favorable, relatively favorable and unfavorable. Currently, the largest coffee-producing region in Brazil has 49.1% of its analyzed area classified as favorable, 39.2% as relatively favorable and 11.7% as unfavorable. In the current scenario, Patrocínio and Três Pontas are locations with high coffee production in which the favorable class is predominant. The state of Minas Gerais has an annual mean of 55.3% of its entire territory apt for the disease, with the highest occurrence between September and March.

CONCLUSIONS

Climate change has a negative impact on the development of coffee leaf rust, mainly in the long term, as in the period of 2081-2100, in which the SSP-5 8.5 scenario led to a decrease in the favorable and unfavorable areas and an increase in the relatively favorable areas of 9.8%, 18.6% and 71.5% for the Brazilian territory, respectively. © 2024 Society of Chemical Industry.

Summer weather perception and preferences in Powsin Culture Park (Warsaw, Poland)

Green areas situated inside the city play a very important role for many aspects. Among other, from the social point of view, they have a positive impact on the life of city habitants: directly improve well-being and health, reduce noise, provide opportunities for activity and recreation, improve the tourist attractiveness of the city, etc. The objective of this study was to assess thermal sensations and preferences of people staying outdoors for recreational purposes in the area of the city park during summer 2019, as well as to identify how bioclimate perceptions are modified by personal factors (physical and physiological). In order to determine the optimum thermal zone for recreation and urban tourism during the summer, the regression model for mean thermal preferences (MTPV) every 1 °C in PET value intervals was calculated, and according to this procedure, the preferable spectrum of thermal conditions for tourism and recreation in Warsaw which is related to the PET value range between 27.3 and 31.7 °C. All age groups indicated the highest frequency of neutral thermal sensation vote, which decreased with feeling more extreme thermal conditions. In the case of classification by the gender, the men more than the women indicated the thermal conditions as neutral, "slightly warm," and "warm." Studies have shown that women were more sensitive than men to extreme thermal sensations especially "hot" and men more often than women indicated greater acceptance for comfortable and warmer thermal conditions.

Visits to the accident and emergency department in hot season of a city with subtropical climate: association with heat stress and related meteorological variables

BACKGROUND

Literature reporting the association between heat stress defined by universal thermal climate index (UTCI) and emergency department visits is mainly conducted in Europe. This study aimed to investigate the association between heat stress, as defined by the UTCI, and visits to the accident and emergency department (AED) in Hong Kong, which represents a subtropical climate region.

METHODS

A retrospective study involving 13,438,846 AED visits in the public sector from May 2000 to September 2016, excluding 2003 and 2009, was conducted in Hong Kong. Age-sex-specific ANCOVA models of daily AED rates on heat stress and prolonged heat stress, adjusting for air quality, prolonged poor air quality, typhoon, rainstorm, year, day of the week, public holiday, summer vacation, and fee charging, were used.

RESULTS

On a day with strong heat stress (32.1 °C ≤ UTCI ≤ 38.0 °C), the AED visit rate (per 100,000) increased by 0.9 (95% CI: 0.5, 1.3) and 1.7 (95% CI: 1.3, 2.1) for females and males aged 19-64 and 4.1 (95% CI: 2.7, 5.4) and 4.1 (95% CI: 2.6, 5.6) for females and males aged ≥ 65, while keeping other variables constant. On a day with very strong heat stress (38.1 °C ≤ UTCI ≤ 46.0 °C), the corresponding rates increased by 0.6 (95% CI: 0.1, 1.2), 2.2 (95% CI: 1.7, 2.7), 4.9 (95% CI: 3.1, 6.7), and 4.7 (95% CI: 2.7, 6.6), respectively. The effect size of heat stress associated with AED visit rates was negligible among those aged ≤ 18. Heat stress showed the greatest effect size for males aged 19-64 among all subgroups.

CONCLUSION

Biothermal condition from heat stress was associated with the health of the citizens in a city with a subtropical climate and reflected in the increase of daily AED visit. Public health recommendations have been made accordingly for the prevention of heat-related AED visits.

Study on air temperature estimation and its influencing factors in a complex mountainous area

Near-surface air temperature (Ta) is an important parameter in agricultural production and climate change. Satellite remote sensing data provide an effective way to estimate regional-scale air temperature. Therefore, taking Gansu section of the upper Weihe River Basin as the study area, using the filtered reconstructed high-quality long-time series normalized difference vegetation index (NDVI), interpolated reconstructed land surface temperature (LST), surface albedo, and digital elevation model (DEM) as the input data, the back-propagation artificial neural network algorithm (BP-ANN) was combined with a multiple linear regression method to estimate regional air temperature, and the influencing factors of air temperature estimation were analyzed. This method effectively compensates for the fact that air temperature data provided by a single station cannot represent regional air temperature information. The result shows that the temperature estimation accuracy is high. In terms of interannual variation, the air temperature in the study area showed a slightly increasing trend, with an average annual increase of 0.047°C. The calculation results of the interannual variation rate of temperature showed that the area with increased air temperature accounted for 75.8% of the total area. In terms of seasonal variation, compared with that in summer and winter, the air temperature rising trend in autumn was obvious, and the air temperature in the middle of the study area decreased in spring, which is prone to frost disasters. LST and NDVI in the study area were positively correlated with air temperature, and their positive correlation distribution areas accounted for 93.62% and 94.34% of the total study area, respectively. NDVI, LST and DEM influence the temperature change in the study area. The results show that there is a significant positive correlation between NDVI and air temperature, and the change of NDVI has a positive effect on the spatiotemporal variation of air temperature. The correlation coefficient between LST and air temperature in the southeast of the study area is negative, and there is a difference. In addition, the correlation coefficient between LST and air temperature in other areas of the study area is positive. The air temperature decreased with elevation, air temperature decreases by 0.27°C every hundred meters.

Behavioural thermal regulation explains pedestrian path choices in hot urban environments

Due to phenomena such as urban heat islands, outdoor thermal comfort of the cities' residents emerges as a growing concern. A major challenge for mega-cities in changing climate is the design of urban spaces that ensure and promote pedestrian thermal comfort. Understanding pedestrian behavioural adaptation to urban thermal environments is critically important to attain this goal. Current research in pedestrian behaviour lacks controlled experimentation, which limits the quantitative modelling of such complex behaviour. Combining well-controlled experiments with human participants and computational methods inspired by behavioural ecology and decision theory, we examine the effect of sun exposure on route choice in a tropical city. We find that the distance walked in the shade is discounted by a factor of 0.86 compared to the distance walked in the sun, and that shadows cast by buildings have a stronger effect than trees. The discounting effect is mathematically formalised and thus allows quantification of the behaviour that can be used in understanding pedestrian behaviour in changing urban climates. The results highlight the importance of assessment of climate through human responses to it and point the way forward to explore scenarios to mitigate pedestrian heat stress.

Spatial and temporal changes of outdoor thermal stress: influence of urban land cover types

Green infrastructure (GI) has emerged as a feasible strategy for promoting adaptive capacities of cities to climate change by alleviating urban heat island (UHI) and thus heat stress for humans. However, GI can also intensify the winter cold stress. To understand the extent of UHI within a city as well as the link between outdoor thermal stress both diurnally and seasonally, we carried out an empirical study in Würzburg, Germany from 2018 to 2020. At sub-urban sites, relative humidity and wind speed (WS) was considerably higher and air temperature (AT) lower compared to the inner city sites. Mean AT of inner city sites were higher by 1.3 °C during summer and 5 °C during winter compared to sub-urban sites. The magnitude followed the spatial land use patterns, in particular the amount of buildings. Consequently, out of 97 hot days (AT > 30 °C) in 3 years, 9 days above the extreme threshold of wet bulb globe temperature of 35 °C were recorded at a centre location compared to none at a sub-urban site. Extreme heat stress could be halved with 30-40% cover of greenspaces including grass lawns, green roofs, and green walls with little compromise in increasing winter cold stress.

Impacts of the Microclimate of a Large Urban Park on Its Surrounding Built Environment in the Summertime

The cooling effect of green spaces as an ecological solution to mitigate urban climate change is well documented. However, the factors influencing the microclimate in the built environment around forest parks, diurnal variations of their impact and their degree of importance have not been explicitly addressed. We attempted to quantify how much various landscape parameters, including land cover and spatial location, impact the ambient air and surface temperature in the area around Beijing’s Olympic Forest Park. Data were taken along strategically located traverses inside and outside the park. We found: (1) The air temperature during the day was 1.0–3.5 °C lower in the park than in the surrounding area; the surface temperature was 1.7–4.8 °C lower; air humidity in the park increased by 8.7–15.1%; and the human comfort index reduced to 1.8–6.9, all generating a more comfortable thermal environment in the park than in the surrounding area. (2) The distance to the park and the green space ratio of the park’s surrounding area are significant factors for regulating its microclimate. A 1 km increase in distance to the park caused the temperature to increase by 0.83 °C; when the green space ratio increased by 10%, the temperature dropped by 0.16 °C on average. The impact of these two parameters was more obvious in the afternoon than in the middle of the day or in the morning. The green space ratio could be used for designing a more stable thermal environment. (3) Land cover affects surface temperature more than it does air temperature. Our data suggest that an urban plan with an even distribution of green space would provide the greatest thermal comfort.

Local Climate Zones, Land Surface Temperature and Air Temperature Interactions: Case Study of Hradec Králové, the Czech Republic

The current application of local climate zones (LCZs) often ends with (inter)zonal comparation of land surface temperature (LST) or air temperature (AT). LST evaluation employs an enhanced concept of LCZs together with cluster analysis for LCZs grouped based on LST. The paper attempts to combine them into a complex approach derived from the case study on a medium-sized Central European city (Hradec Králové, the Czech Republic). In particular, the paper addresses the following. (i) The relation of LST and AT, when the daily course of temperature profile ranging clear off the surface up to 2 m was fitted by a rational 2D function. The obtained equation enables derivation of the AT from LST and vice versa. (ii) The differences in thermal response of LCZs based on LST or AT, where the highest average LST and average maximum LST show LCZs 10, 2, 3 and 8, i.e., with a significant proportion of artificial surfaces. The cluster of LCZs with a significant representation of vegetation, LCZs 9, B, D, A and G, have significantly lower LST. (iii) The contribution of LCZs to understanding of LST/AT relation and whether their specific relation could be expected in particular LCZs, when subsequent interaction assessment of LST and AT revealed statistically their significant correlation in LCZs for certain cases.

Technological opportunities for sensing of the health effects of weather and climate change: a state-of-the-art-review

Sensing and measuring meteorological and physiological parameters of humans, animals, and plants are necessary to understand the complex interactions that occur between atmospheric processes and the health of the living organisms. Advanced sensing technologies have provided both meteorological and biological data across increasingly vast spatial, spectral, temporal, and thematic scales. Information and communication technologies have reduced barriers to data dissemination, enabling the circulation of information across different jurisdictions and disciplines. Due to the advancement and rapid dissemination of these technologies, a review of the opportunities for sensing the health effects of weather and climate change is necessary. This paper provides such an overview by focusing on existing and emerging technologies and their opportunities and challenges for studying the health effects of weather and climate change on humans, animals, and plants.

Comparison of Ecohydrological and Climatological Zoning of the Cities: Case Study of the City of Pilsen

Standardized delimiting of local climate zones (LCZ) will be better applicable to the urban adaptation to climate change when the ecohydrological properties of LCZ units are known. Therefore, the properties of LCZ units based on the methodology of ecohydrological zoning of the urban landscape, which was created in GIS as a basis for planning blue-green infrastructure of cities in the Czech Republic, are presented in the paper. The goal of this study is to compare approaches and results of our own ecohydrological zonation and standardized LCZ delimiting in the city of Pilsen. Both methodological approaches differ in input data, resolution details and parameters used. The results showed that the areas of the individual LCZ classes show different levels of ecohydrological qualities. Internal heterogeneity of LCZ classes demonstrated by variance of ecohydrological parameters’ values can be partly explained by different techniques and data sources for delimitation of both zonations, but by different sets of delimitation criteria. The discussion is held on the importance of terrain slope for supplementing the LCZ classification. A case study can be a stimulus for further development of holistic urban zoning methodologies that would take into account both climatological and ecohydrological conditions.

High-Resolution Modelling of Thermal Exposure during a Hot Spell: A Case Study Using PALM-4U in Prague, Czech Republic

The modelling of thermal exposure in outdoor urban environments is a highly topical challenge in modern climate research. This paper presents the results derived from a new micrometeorological model that employs an integrated biometeorology module to model Universal Thermal Climate Index (UTCI). This is PALM-4U, which includes an integrated human body-shape parameterization, deployed herein for a pilot domain in Prague, Czech Republic. The results highlight the key role of radiation in the spatiotemporal variability of thermal exposure in moderate-climate urban areas during summer days in terms of the way in which this directly affects thermal comfort through radiant temperature and indirectly through the complexity of turbulence in street canyons. The model simulations suggest that the highest thermal exposure may be expected within street canyons near the irradiated north sides of east–west streets and near streets oriented north–south. Heat exposure in streets increases in proximity to buildings with reflective paints. The lowest heat exposure during the day may be anticipated in tree-shaded courtyards. The cooling effect of trees may range from 4 °C to 9 °C in UTCI, and the cooling effect of grass in comparison with artificial paved surfaces in open public places may be from 2 °C to 5 °C UTCI. In general terms, this study illustrates that the PALM modelling system provides a new perspective on the spatiotemporal differentiation of thermal exposure at the pedestrian level; it may therefore contribute to more climate-sensitive urban planning.