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Owing to rapid urbanization, the Beijing–Tianjin–Hebei region in China faces considerable urban heat island (UHI) effects, which can be mitigated by blue-green space construction. In this study, we used multi-source remote sensing products and the InVEST model's urban cooling module to analyze the spatiotemporal changes in blue-green space cooling effects from 1990 to 2020. The wavelet coherence theory was used to explore these changes, as well as the environmental factors that affect cooling. The key findings indicate that the cooling effect is closely related to urbanization, as similar trends and significant temporal differences in cooling indices were observed in central urban areas, the urban fringe, and the city center. In addition, climatic factors such as temperature and precipitation substantially influenced cooling, with an average wavelet coherence of 0.88. Seasonal variations in cooling were notable, with temperature exhibiting the best coherence across all time–frequency scales (averaging 0.55). The findings highlight the critical role of blue-green spaces for mitigating UHI effects, which provides scientific insights for urban planning and environmental management. [ABSTRACT FROM AUTHOR]

Urban areas with parks tend to have the best outdoor thermal comfort in regions with high urban heat island effects during summer. This study analyzed the synergistic cooling effects of 94 urban parks and the adjacent built-up areas in six districts of Xi'an City using four cooling indicators: park cooling intensity (PCI), park cooling area (PCA), park cooling effect (PCE), and park cooling gradient (PCG). The results showed that 84 out of 94 parks exhibited significant cooling effects, with an average PCI of 1.98 °C, PCA of 51.7 ha, PCE of 6.6, and PCG of 8.2 °C/km. Correlation analyses indicated that the intrinsic park attributes, external buffer zone building height, and building density were the main factors affecting the cooling effect. The park landscape configuration, building height, and density significantly influenced the PCI and PCG, while the park shape and size were crucial for the PCA (positive) and PCE (negative). The optimal park areas for improving the thermal environment were identified as 26 ha (cooling area focus, building density <13%) and 15 ha (cooling intensity focus, building height <21 m, density >32%). This study provides theoretical guidance for planning urban parks and the surrounding areas based on cooling effects, offering insights for future climate resilience planning. [ABSTRACT FROM AUTHOR]

Abstract Rapid urbanization has led to increasingly prominent urban heat island phenomena and social inequality. It is urgent to quantify the threshold area of urban parks from multiple perspectives to maximize the cooling effect and improve the equity of park cooling services. Using 33 urban parks in Harbin City as research objects, four indices, i.e., park cooling intensity (PCI), park cooling distance (PCD), park cooling area (PCA), and park cooling efficiency (PCE), were used to explore the park cooling effect and the threshold value of efficiency (TVoE) of the size. The OD (origin–destination) matrix model was constructed to assess the spatial accessibility from the community to the cooling range. The Gini coefficient was used to assess the equity of cooling range accessibility. The relative contribution of each influencing factor to the cooling indicator was quantified through regression modeling. The results showed that the average PCI was 3.27 ℃, the average PCD was 277 m, the average PCA was 115.35 ha, and the average PCE was 5.74. Gray space area was the dominant factor for PCI, PCD, and PCA (relative contributions of 100%, 31%, and 19%, respectively). Park area was the dominant factor for PCE (relative contribution of 28%). The TVoE of park sizes based on PCA and PCE were calculated as 82.37 ha and 2.56 ha, respectively. 39.2% and 94.01% of communities can reach cooling ranges within 15 min in walk mode and transit mode, respectively. Approximately 18% of neighborhood residents are experiencing severe inequities in cooling range accessibility. This study can guide park design that maximizes cooling effects, as well as inform city planners on more equitable allocation of urban park resources.

One of the useful features of 3D-printed specimens of recycled polyethylene terephthalate glycol (R-PETG) is the ability to repetitively develop free recovery as well as the work-generating, shape-memory effect. This behavior is enabled by the R-PETG's capacity to stiffen during cooling, thus allowing for a new temporary shape to be induced. Aiming to devise an explanation for the polymer's stiffening, in this study, the variation in some of the R-PETG's parameters during cooling are emphasized and discussed. The evolution of an R-PETG filament's shape was monitored during room-temperature-bending heating–cooling cycles. Straight-shape recovery and the complete loss of stiffness were observed at the start and the end of heating, respectively, followed by the forced straightening of the filament, performed by the operator, around 40 °C, during cooling. The tests performed by dynamic mechanical analysis disclosed the rise of the storage modulus (E') after 100 °C heating followed by either liquid-nitrogen- or air-cooling to room temperature, in such a way that E' was always larger after cooling than initially. Static tests emphasized a peculiar stress variation during a heating–cooling cycle applied in air, within the heating chamber of the tensile testing machine. Tensile-failure tests were performed at −10 °C at a rate of 100 mm/min, with specimens printed at various deposition directions between 10 and 40° to the transversal direction. The specimens printed at 40°, which had the largest ultimate strains, were broken with tensile rates between 100 and 500 mm/min. Deformation rate increase favored the shift from crazing to delamination failure modes. The correlation between the structural changes, the sharp E' increase on heating, and the stiffening induced by cooling represents a novel approach that enables the use of 3D-printed R-PETG for the fabrication of the active parts of low-priced lightweight resettable actuators. [ABSTRACT FROM AUTHOR]

Rapid urbanization has led to increasingly prominent urban heat island phenomena and social inequality. It is urgent to quantify the threshold area of urban parks from multiple perspectives to maximize the cooling effect and improve the equity of park cooling services. Using 33 urban parks in Harbin City as research objects, four indices, i.e., park cooling intensity (PCI), park cooling distance (PCD), park cooling area (PCA), and park cooling efficiency (PCE), were used to explore the park cooling effect and the threshold value of efficiency (TVoE) of the size. The OD (origin–destination) matrix model was constructed to assess the spatial accessibility from the community to the cooling range. The Gini coefficient was used to assess the equity of cooling range accessibility. The relative contribution of each influencing factor to the cooling indicator was quantified through regression modeling. The results showed that the average PCI was 3.27 ℃, the average PCD was 277 m, the average PCA was 115.35 ha, and the average PCE was 5.74. Gray space area was the dominant factor for PCI, PCD, and PCA (relative contributions of 100%, 31%, and 19%, respectively). Park area was the dominant factor for PCE (relative contribution of 28%). The TVoE of park sizes based on PCA and PCE were calculated as 82.37 ha and 2.56 ha, respectively. 39.2% and 94.01% of communities can reach cooling ranges within 15 min in walk mode and transit mode, respectively. Approximately 18% of neighborhood residents are experiencing severe inequities in cooling range accessibility. This study can guide park design that maximizes cooling effects, as well as inform city planners on more equitable allocation of urban park resources. [ABSTRACT FROM AUTHOR]

Camping has become a popular outdoor activity in China. However, the long and scorching summers in China's hot and humid regions pose challenges for campsites in maintaining thermal comfort. Therefore, we explored the impact of tree species and planting methods on the thermal comfort of urban campsites in hot and humid areas using the ENVI-met model to simulate the conditions of the study area. The reliability of the model was validated by comparing the simulated values of air temperature (Ta) and relative humidity (RH) with field measurements. We conducted an in-depth analysis of common trees in hot and humid areas and analyzed the effects of five tree species and four tree planting forms on the microclimate of campsites in such areas, using the physiological equivalent temperature (PET) as the evaluation index of thermal comfort. The results indicated that: (1) trees with larger crown widths were most effective in improving outdoor thermal comfort. The ability of trees to regulate microclimate was more influenced by crown width than by leaf area index (LAI), and (2) trees planted in patches provided the highest level of thermal comfort, whereas single trees provided the lowest. However, relying solely on tree planting made it difficult to significantly reduce outdoor heat stress. Therefore, other methods such as increasing ventilation or mist spray should be adopted to modify camping area. This study provides a reference for the planting design of outdoor campsites in hot and humid regions of China. [ABSTRACT FROM AUTHOR]

Research has demonstrated that urban green spaces play a crucial role in mitigating the severe urban heat island (UHI) effect. However, existing studies often suffer from limitations such as the neglect of the cooling effect of water bodies within the green spaces and incomplete considerations of the overall cooling effect. These limitations may lead to inaccuracies in the research findings. Therefore, the present study takes the city of Xi'an as a case study to explore the optimal green space size for achieving efficient cooling. The results indicate that (i) urban green spaces exhibit robust cooling effects, with variations observed among the various types; (ii) for community parks without water, and for street gardens, the optimal areas of these green spaces are 3.44 and 0.83 hectares, respectively; (iii) for community parks with water, the area of internal water bodies should ideally be maintained at around 29.43% of the total green space area in order to achieve an optimal cooling efficiency. In conclusion, this study introduces a new perspective and new optimization methods for urban green space planning, thereby offering scientific guidance to urban planners in formulating effective development and management policies and urban planning schemes. [ABSTRACT FROM AUTHOR]

The heat absorption of the railbed mainly originates from the embankment slope in permafrost regions. A novel ventilated slope (NVS) with a double‐layer convection channel is proposed and verified. By applying this method to the Qinghai–Tibet Railway (QTR), the annual average temperature at the 10 cm depth below the embankment slope surface under NVS was reduced by 4.95°C. The freezing index at the 10 cm depth of NVS was 1.78 times higher than that of the slope without any cooling approaches. The numerical simulation results showed that heat was accumulated for the conventional embankment, while heat was released from the railbed after the application of NVS. With the cooling effect of NVS, the 0°C isotherm would rise above the original natural ground surface in the 2nd year after the embankment construction. A low‐temperature region of −2°C would be observed in the underlying permafrost by the 10th year. The underlying permafrost would remain frozen in the 50th year. This study provides a novel method for protecting the underlying permafrost in permafrost regions. [ABSTRACT FROM AUTHOR]

Green city areas are crucial in mitigating the Urban Heat Island Effect (UHI). However, the cooling effect of green city areas can be influenced by the surrounding complex urban spatial environment. This study focuses on Changsha, a subtropical city in China, where 40 green city areas were screened and analyzed. The study aims to quantify the specific impact of urban spatial morphology on the cooling effect of green city areas. Through statistical correlation and regression analysis, this study focused on six urban spatial morphology indicators: building density (BD), building floor area ratio (BFR), building volume density (BVD), building evenness index (BEI), building average height (BH), and building height standard deviation (BSD). The results indicate that the cooling effect of green city areas could be influenced by urban spatial morphology. Factors such as BD, BFR, BH, and BSD were found to be significantly correlated with the cooling effect of green city areas, with BH showing the strongest influence. BD and BFR were negatively correlated, while BH and BSD were positively correlated. The range values of BD, BFR, BH, and BSD were determined to achieve the optimal conditions for the cooling effect of green city areas. Additionally, the relative position of the green city areas in the neighboring urban areas affects the cooling effect of the green city areas. The cooling effect is most pronounced in the urban area situated to the south of the green city areas. These findings provide a solid foundation for urban planning around green city spaces and offer scientifically sound evidence for mitigating the UHI. [ABSTRACT FROM AUTHOR]

Urban greenery is a strategy to improve the thermal environment in urban areas affected by heat islands and global warming. These phenomena can harm the citizens' quality of life. Researchers have investigated the thermal benefits of urban vegetation, but only a few have explored its complexities across diverse urban scales. Understanding these variations is critical for precise analysis, customized solutions, efficient resource allocation, and enhancing urban living quality while promoting sustainability and climate resilience. This paper reviews 250 scientific articles about the relationship between greenspace and the urban thermal environment published between 2010 and 2023 through urban scales. It summarizes the parameters and findings of greenery's contribution to cooling the urban environment. The data reveal that most studies concentrated on the block scale, public open spaces, neighborhoods, parks, grouped vegetation, mixed arrangements, high vegetation, spatial parameters, and the use of air temperature data to report their findings. The cooling-effect evidence shows that the block scale has an average mitigation range of 0.7–2.7 °C, the neighborhood scale of 1.1–2.9 °C, and the city scale of 0.5–2.2 °C. Furthermore, it is critical to define reliable research methods and perform thorough software validation to assess model performance and establish guidelines for urban-landscape design accurately. [ABSTRACT FROM AUTHOR]

Cooling spaces have an optimistic influence on surface urban heat islands (SUHI). Blue spaces benefit from balancing the changing climate and heat variations. Because of the rapid deforestation and SUHI increase, the climate is gradually changing in Paschim Bardhhaman, West Bengal state, India. Paschim Bardhhaman has two sectors: specifically, Durgapur is the main industrial centre and Asansol has coal mines. This investigation aims to categorize spatiotemporal variations and seasonal differences in cooling spaces and their influence on SUHI, land use and land cover (LULC), and thermal differences using Landsat datasets for the years 1992, 2004, 2012, and 2022 in summer and winter. The coal mining and industrial range decreased from 10,391.92 (1992) to 3591.1 ha (2022), respectively. Open pit mining distresses fresh water by heavy water uses in ore processing, and mining water was applied to excerpt minerals. Among the two sub-divisions, the blue space amount was higher in Asansol because mining actions were higher in Asansol than in Durgapur. The open vegetation volume has reduced from 46,441.03 (1992) to 25,827.55 ha (2022) and dense vegetation has erased from 7368.02 (1992) to 15,608.56 ha (2022). Dense vegetation improved because of heavy precipitation in those regions. Mostly, Raghunathpur, Saraswatiganja, Bhagabanpur, Bistupur, Paschim Gangaram, Garkilla Kherobari, and Gourbazar have dense vegetation. The outcomes similarly demonstrate that the total built-up part has increased by 8412.82 ha in between 30 years. The built-up zone changes near the southeast and western Paschim Bardhhaman district. Those region needs appropriate attention and planning to survive soon. [ABSTRACT FROM AUTHOR]

Accurately calculating the annual yield of floating PV (FPV) systems necessitates incorporating appropriate FPV-specific heat loss coefficients into the calculation, including both wind-dependent and wind-independent factors. The thermal behavior of several FPV systems has been investigated within this study, through the analysis of heat loss coefficients across various system sizes and configurations. Over a one-year period, data were collected from two measurement sites with three distinct systems: two ~50 kWp demonstrator-scale setups of Solarisfloat (azimuthal tracking) and Solar Float (East-West orientation) and a 2 MWp commercial-scale East–West system by Groenleven. The Solarisfloat demonstrator revealed a wind-dependent heat loss coefficient of 3.2 W/m3Ks. In comparison, the Solar Float demonstrator system displayed elevated wind-dependent heat loss coefficients, measuring 4.0 W/m3Ks for the east-facing module and 5.1 W/m3Ks for the west-facing module. The Groenleven system, which shares design similarities with Solar Float, showed lower wind-dependent heat loss coefficients of 2.7 W/m3Ks for the east-facing module and 2.8 W/m3Ks for the west-facing module. A notable discrepancy in the wind-dependent coefficients, particularly evident under a north wind direction, indicates a more efficient convective cooling effect by the wind on the demonstrator scale system of Solar Float. This could possibly be attributed to improved wind flow beneath its PV modules, setting it apart from the Groenleven system. Additionally, a thermal model founded on a 'balance-of-energy' methodology, integrating water temperature as a variable was introduced. The heat loss coefficient, dependent on the surface water temperature, fluctuated around zero, depending on whether the water temperature surpassed or fell below the ambient air temperature. It can be concluded that it is not of added value to introduce this floating specific heat loss coefficient parameter, as this parameter can be integrated in the wind speed independent Uc parameter. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of South Architecture / Nanfang Jianzhu is the property of South Architecture Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims Understanding of the tissue cooling properties of cryoballoon ablation during pulmonary vein (PV) isolation is lacking. The purpose of this study was to delineate the depth of the tissue cooling effect during cryoballoon freezing at the pulmonary venous ostium. Methods and results A left atrial-PV model was constructed using a three-dimensional printer with data from a patient to which porcine thigh muscle of various thicknesses could be affixed. The model was placed in a 37°C water tank with a PV water flow at a rate that mimicked biological blood flow. Cryofreezing at the PV ostium was performed five times each for sliced porcine thigh muscle of 2, 4, and 6 mm thickness, and sliced muscle cooling on the side opposite the balloon was monitored. The cooling effect was assessed using the average temperature of 12 evenly distributed thermocouples covering the roof region of the left superior PV. Tissue cooling effects were in the order of the 2, 4, and 6 mm thicknesses, with an average temperature of −41.4 ± 4.2°C for 2 mm, −33.0 ± 4.0°C for 4 mm, and 8.0 ± 8.7°C for 6 mm at 180 s (P for trend <0.0001). In addition, tissue temperature drops were steeper in thin muscle (maximum temperature drop per 5 s: 5.2 ± 0.9°C, 3.9 ± 0.7°C, and 1.3 ± 0.7°C, P for trend <0.0001). Conclusion The cooling effect of cryoballoon freezing is weaker in the deeper layers. Cryoballoon ablation should be performed with consideration to myocardial thickness. [ABSTRACT FROM AUTHOR]

Copyright of Detergent & Cosmetics is the property of Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Thermal events in lead-acid batteries during their operation play an important role; they affect not only the reaction rate of ongoing electrochemical reactions, but also the rate of discharge and self-discharge, length of service life and, in critical cases, can even cause a fatal failure of the battery, known as "thermal runaway." This contribution discusses the parameters affecting the thermal state of the lead-acid battery. It was found by calculations and measurements that there is a cooling component in the lead-acid battery system which is caused by the endothermic discharge reactions and electrolysis of water during charging, related to entropy change contribution. Thus, under certain circumstances, it is possible to lower the temperature of the lead-acid battery during its discharging. The Joule heat generated on the internal resistance of the cell due to current flow, the exothermic charging reaction, and above all, the gradual increase in polarization as the cell voltage increases during charging all contribute to the heating of the cell, overtaking the cooling effect. Of these three sources of thermal energy, Joule heating in polarization resistance contributes the most to the temperature rise in the lead-acid battery. Thus, the maximum voltage reached determines the slope of the temperature rise in the lead-acid battery cell, and by a suitably chosen limiting voltage, it is possible to limit the danger of the "thermal runaway" effect. The overall thermal conditions of the experimental cell are significantly affected by the ambient temperature of the external environment and the rate of heat transfer through the walls of the calorimeter. A series of experiments with direct temperature measurement of individual locations within a lead-acid battery uses a calorimeter made of expanded polystyrene to minimize external influences. A hitherto unpublished phenomenon is discussed whereby the temperature of the positive electrode was lower than that of the negative electrode throughout the discharge, while during charging, the order was reversed and the temperature of the positive electrode was higher than that of the negative electrode throughout the charge. The authors relate this phenomenon to the higher reaction entropy change of the active mass of the positive electrode than that of the negative electrode. [ABSTRACT FROM AUTHOR]

Abstract Urban water bodies can effectively mitigate the urban heat island effect and thus enhance the climate resilience of urban areas. The cooling effect of different water bodies varies, however, the cooling heterogeneity of different sections of a single watercourse or river network is rarely considered. Based on various satellite images, geospatial approaches and statistical analyses, our study confirmed the cooling heterogeneity from spatial and seasonal perspectives of the Suzhou Outer-city River in detail in the urban area of Suzhou, China. The cooling effect of the river was observed in the daytime in four seasons, and it is strongest in summer, followed by spring and autumn, and weakest in winter. The combination of the width of the river reach, the width and the NDVI value of the adjacent green space can explain a significant part of the cooling heterogeneity of the different river sections in different seasons. Land surface temperature (LST) variations along the river are more related to the width of the river reach, but the variations of the cooling distance are more related to the adjacent green space. The cooling effect of a river reach could be enhanced if it is accompanied by green spaces. In addition, the cooling effect of a looping river is stronger on the inside area than on the outside. The methodology and results of this study could help orient scientific landscape strategies in urban planning for cooler cities.

Urban water bodies can effectively mitigate the urban heat island effect and thus enhance the climate resilience of urban areas. The cooling effect of different water bodies varies, however, the cooling heterogeneity of different sections of a single watercourse or river network is rarely considered. Based on various satellite images, geospatial approaches and statistical analyses, our study confirmed the cooling heterogeneity from spatial and seasonal perspectives of the Suzhou Outer-city River in detail in the urban area of Suzhou, China. The cooling effect of the river was observed in the daytime in four seasons, and it is strongest in summer, followed by spring and autumn, and weakest in winter. The combination of the width of the river reach, the width and the NDVI value of the adjacent green space can explain a significant part of the cooling heterogeneity of the different river sections in different seasons. Land surface temperature (LST) variations along the river are more related to the width of the river reach, but the variations of the cooling distance are more related to the adjacent green space. The cooling effect of a river reach could be enhanced if it is accompanied by green spaces. In addition, the cooling effect of a looping river is stronger on the inside area than on the outside. The methodology and results of this study could help orient scientific landscape strategies in urban planning for cooler cities. [ABSTRACT FROM AUTHOR]

Urban trees are not only a core component of natural infrastructure but also an effective way to mitigate urban heat with nature-based solutions. Comprehensively revealing the cooling effects of trees and their drivers is valuable for enhancing urban climate resilience and promoting sustainable development. While existing studies have investigated the cooling effects of two-dimensional characteristics of trees, there has been limited consideration of the effects of vertical structure, especially in various climatic zones across the globe. In this study, we employed the Google Earth Engine cloud platform and the random forest algorithm to comprehensively assess the impact of three-dimensional (3D) characteristics of trees on land surface temperature across 596 cities worldwide. Results suggest that LST is generally lower in tree-covered areas than their surrounding built-up land, especially in the summer, with an average decrease of about 2.13 °C. We also found a significant negative correlation between tree canopy height and LST (∼−0.83). Specifically, the mean LST decreases by about 0.16 ℃ for every 1m increase in tree height. Globally, the average cooling intensity of trees is 1.86 °C, and is about 1.06 °C higher in summer than in winter. It is worth noting that during winter, the cooling effect of trees is more pronounced closer to the equator. In addition, the 3D characteristics of trees contribute more significantly to cooling intensity compared to their surrounding environmental factors. This study not only fills a global knowledge gap regarding the impact of 3D features of trees on LST, but also provides valuable insights into urban planning and management in response to climate change. [ABSTRACT FROM AUTHOR]

The increased rainfall in summer induces warming and humidification of the Qinghai–Tibet Plateau, significantly affecting the temperature boundaries and cooling effects of the crushed-rock embankment (CRE). The crucial issue of quantitatively characterizing the hydrothermal changes and the cooling effects of CRE has not been considered in previous research. Therefore, an experimental study on the open crushed-rock layer (CRL) under rainfall infiltration was conducted. Based on the freezing and thawing indices and heat budget of the underground layer, the influence of summer rainfall on the cooling effect of open CRL was evaluated. The results showed that the periodic average temperature of the underground layer first decreased to negative values and then increased to positive values affected by summer rainfall. The freezing and thawing indices and their ratio gradually decreased. The cooling effect of open CRL was weakened, with a maximum decrease of 15.20%. After summer rainfall, the volumetric water content and heat flux of the underground layer increased sharply and then decreased rapidly, and the maximum increases for the peak values were 28.8% and 88.81 W/m2, respectively. The average volumetric water content for each cycle gradually increased and reached saturation. Meanwhile, heat absorption gradually increased, and the heat release of the underground layer first increased and then decreased with the cumulative rainfall. The large amount of latent heat released by the water–ice phase change was a key factor for the degradation of the cooling effect of open CRL. [ABSTRACT FROM AUTHOR]

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Data from national meteorological stations in 90 counties of Jiangxi province during 2012-2021 and 8 microclimate stations in rice fields during 2017-2021 were used to analyze the differences in temperature between rice fields and stations, and the statistical results based on H1 (NS)(daily max temperature of national stations ≥35 °C), H1 (RS)(daily max temperature of rice fields ≥35 °C), H2 (NS)(daily max temperature of national stations ≥37°C) and H2 (RS) (daily max temperature of rice fields ≥ 37 °C ) were compared. Furthermore, proposing high-temperature damage indicators more suitable for early rice in Jiangxi, which would promoting capabilities of high-temperature monitoring and defense. The results showed that: (1) compared with the national stations, the rice fields had a cooling effect, and the Tmax(daily maximum temperature), T(daily average temperature), and Tmin(daily minimum temperature) were 0.6 °C, 0.4 °C, and 0.3 °C lower than national stations. What's more, the cooling effect increased with the growth of early rice, which showed as heading-maturity period>transplanting-booting period>sowing-transplanting period. (2) The cooling effect was higher in sunny days than in cloudy and rainy days during the high temperature period, and T, Tmax and Tmin of early rice field were 0.7 °C, 0.8 °C and 0.6 °C lower than that of the national stations. On cloudy and rainy days, the decrease in temperature of rice fields was similar. (3) There were significant differences in daily and hourly air temperature between 6 rice fields and the corresponding national stations during H1 (NS) heat damage occurred, and the cooling intensity of the rice field was greater at night than in the daytime. The Tmax, T and Tmin of the 6 fields were generally about 1.2 °C lower, which was strongest in Jinxi filed with T, Tmax and Tmin was 1.5 °C, 1.1 °C and 2.6 °C lower. (4) H1 (NS) was the largest and H2 (RS) was the smallest in terms of the number of counties affected by heat damage, the average duration, the average yield reduction simulation value of affected counties and the simulation value of the whole in recent 10 years based on different heat damage index. There was no significant difference in the result of average duration, the simulated average yield reduction rate of affected counties, and the simulated yield reduction rate of the whole based on H2 (NS) and H1 (RS), while they were all different with the result based on H1 (NS) or H2 (RS). And the simulated value of the reduction rate of the whole calculated by H2 (NS) was closer to the actual value. Therefore, national stations Tmax ≥37°C was more suitable as an index of heat damage for early rice in Jiangxi. [ABSTRACT FROM AUTHOR]

Cirrus thinning, as one kind of geoengineering approach, not only cools our planet but also enhances the amount of sunlight reaching the Earth's surface (brightening effect). This study delves into the brightening effect induced by cirrus thinning with a flexible seeding method. The thinning of cirrus clouds alone leads to a considerable globally averaged cooling effect (−2.46 W m−2), along with a notable globally averaged brightening effect (2.19 W m−2). Cirrus thinning also results in substantial reductions in the cloud radiative effects of the lower mixed-phase and liquid clouds. While these reductions counteract the cooling effect from cirrus clouds, they enhance the brightening effect from cirrus clouds. Consequently, the brightening effect caused by cirrus seeding (4.69 W m−2) is considerably stronger than its cooling effect (−1.21 W m−2). Furthermore, due to the more pronounced changes from the mixed-phase and liquid clouds at low and mid-latitudes, the cooling effect is primarily concentrated at high latitudes. In contrast, the brightening effect is stronger over most low- and mid-latitude regions. Overall, cirrus thinning could lead to a notable brightening effect, which can be leveraged to offset the dimming effect (the opposite of the brightening effect) of other geoengineering approaches. [ABSTRACT FROM AUTHOR]

This study 46Tinvestigated 46Tthe cooling effect of an Earth Water-Air Heat Exchanger (EWAHE) device for ventilation applications. To address the lack of data on EWAHE performance in moderate climates, we measured temperature parameters (inlet-outlet, indoor-outdoor, water, and soil) continuously for three days. Air temperatures, air flowrate, light intensity are measured using a multi-channel data logger with several sensors. Results showed that the EWAHE effectively reduced indoor air temperature by an average of 7.5°C with a maximum reduction of 9.3°C, offering a promising passive cooling solution for buildings. The primary limitation of this study is that it requires open space around the building to place the device, so this method is inappropriate for building in a dense urban area. 43TFuture studies could investigate the association between ground-water cooling effect and natural ventilation without using energy for air circulation. [ABSTRACT FROM AUTHOR]

The appropriate design of urban ventilation corridors (VCs) can improve the urban thermal environment, thereby reducing urban energy consumption and promoting sustainable urban development. However, existing research lacks a comprehensive grasp of the characteristics of VCs from multiple dimensions and quantitative analysis of its cooling effect. We propose a novel approach based on data mining to comprehensively consider the morphological and environmental characteristics of VCs and explore the correlation between VC characteristics and the cooling effect. Selecting Nanjing as an example, a comprehensive index system was constructed, the cooling effect of the VC was investigated, and the optimal range of VC index with different underlying surface types was obtained. Results revealed that the cooling effect is closely related to the underlying surface, leading to a temperature difference of up to 5.4 °C. The VC cooling range can vary from 13 to 600 m. The recommended optimal parameter intervals for different VCs were determined. Finally, targeted strategies to alleviate the heat island effect were proposed for different underlying surface types. The study output contributes to the design of VCs, which is of great significance in alleviating the urban heat island effect and promoting sustainable development of cities. [ABSTRACT FROM AUTHOR]

In natural and altered environments, the Ecosystem Services (ES) provided by the presence of vegetation, especially regulating ES such as climate regulation and air pollutant removal, are essential to improve human health and well-being. In this study, we focused on a tropical-subtropical river basin which covers urban, peri-urban and rural landscape types of a Brazilian municipality located in the ecotone between the Atlantic Forest and the Cerrado (Brazilian savannah). The research aimed to assess the current state of ES and bird richness (as a biodiversity indicator) and their relationships across an urban-rural-natural gradient. We assessed the cooling effect (as microclimate regulation indicator), air pollutant removal (PM10), nature-based recreation opportunities and bird richness and analysed the variations associated with a shift in the prevailing land- cover types along a gradient of urbaniszation. The results indicated a higher bird richness in peri-urban and rural landscapes, as well as greater pollutant removal and cooling effect provided by vegetation. However, recreation opportunities provided mainly by human infrastructure were higher inside the urban zone and in some peri-urban areas. The landscape type significantly influenced the availability and intensity of these four variables (p < 0.001). Bird richness, air pollutant removal, and cooling effect were positively correlated (r > 0.539; p ≤ 0.048);, however, a trade-off between them and recreation opportunities (r = -0.59, R2 = 0.348, p < 0.001) was found. We simulated possible scenarios of reforestation actions in urban areas to predict the ES values when vegetation cover area is increased. According to the results, the urban planning and efforts to improve nNature-based solutions in the studied river basin should consider the observed trade-off to promote sustainable nature-based recreation opportunities in places with higher values of ES (cooling effect, air pollutant removal, and bird richness) and/or to increase the ES values in urban landscape through environmental policies, such as reforestation.

Rapid urbanization and unplanned development have posed a threat to the thermal environment in a country like China. The urban heat island (UHI) phenomenon is one of the most serious issues because of its strong relation to thermal comfort, air pollution, and public health. The water bodies, as an important component of the urban ecosystem, are generally considered a vital resource to mitigate the UHI. This study provides direct evidence with the help of satellite observation and field measurement data using the mono-window algorithm, spatial buffer analysis, and linear regression methods to explore how the stream water affects the local temperature variation. The results showed that Land use/cover change (LUCC) and Land surface temperature (LST) on both banks of the Bahe River changed significantly. The LST of the river was significantly massively reduced within the distance range of 300 to 500 m, and 400 to 600 m, with an average temperature dip from 3.7 to 2.8 °C, and from 3.2 to 1.7 °C respectively were during the summer on east and west river banks. In addition, the surrounding LUCC composition and configuration could strongly affect the maximum cooling scale. The results provide insights for urban planners and managers to arrange the LUCC composition between the river design in urban areas and the cooling effect demands.

Owing to rapid urbanization, the Beijing–Tianjin–Hebei region in China faces considerable urban heat island (UHI) effects, which can be mitigated by blue-green space construction. In this study, we used multi-source remote sensing products and the InVEST model’s urban cooling module to analyze the spatiotemporal changes in blue-green space cooling effects from 1990 to 2020. The wavelet coherence theory was used to explore these changes, as well as the environmental factors that affect cooling. The key findings indicate that the cooling effect is closely related to urbanization, as similar trends and significant temporal differences in cooling indices were observed in central urban areas, the urban fringe, and the city center. In addition, climatic factors such as temperature and precipitation substantially influenced cooling, with an average wavelet coherence of 0.88. Seasonal variations in cooling were notable, with temperature exhibiting the best coherence across all time–frequency scales (averaging 0.55). The findings highlight the critical role of blue-green spaces for mitigating UHI effects, which provides scientific insights for urban planning and environmental management.

The near‐surface boundary layer can mediate the response of mountain glaciers to external climate, cooling the overlying air and promoting a density‐driven glacier wind. The fundamental processes are conceptually well understood, though the magnitudes of cooling and presence of glacier winds are poorly quantified in space and time, increasing the forcing uncertainty for melt models. We utilize a new data set of on‐glacier meteorological measurements on three neighboring glaciers in the Swiss Alps to explore their distinct response to regional climate under the extreme 2022 summer. We find that synoptic wind origins and local terrain modifications, not only glacier size, play an important role in the ability of a glacier to cool the near‐surface air. Warm air intrusions from valley or synoptically‐driven winds onto the glacier can occur between ∼19% and 64% of the time and contribute between 3% and 81% of the total sensible heat flux to the surface during warm afternoon hours, depending on the fetch of the glacier flowline and its susceptibility to boundary layer erosion. In the context of extreme summer warmth, indicative of future conditions, the boundary layer cooling (up to 6.5°C cooler than its surroundings) and resultant katabatic wind flow are highly heterogeneous between the study glaciers, highlighting the complex and likely non‐linear response of glaciers to an uncertain future. Plain Language Summary: The presence of a 0°C ice surface cools the near‐surface air and generates a unique micro‐climate that complicates a glaciers response to future warming. Using a new data series on three glaciers during an extreme summer of 2022, we explore how variable this cooling is in space and time and investigate the factors that can control it. We focus largely on the role of valley and synoptic winds that are found to affect glaciers of varying size and orientation differently, influencing the amount of heat transfer to the ice surface that glaciers receive from outside its own micro‐climate. Moreover, we find that the presence of glacier winds can act to enhance or reduce overall heat transfer to the glacier, depending on the wind strength and degree of boundary layer disruption. We highlight the complexities that are ignored in simpler melt modeling frameworks and demonstrate how, especially under extreme summer heat, indicative of future conditions, static parameters to relate glacier melt to temperature are likely to be inappropriate. Key Points: Glacier size and alignment with valley/synoptic wind gradients control the magnitude of near‐surface coolingValley/synoptic winds can occur between 19% and 64% of the time and contribute between 3% and 81% of total sensible heat to the ice surfaceLocalized cooling and turbulence in the boundary layer increase the complexity and non‐linearity of glacier response to climate [ABSTRACT FROM AUTHOR]

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A method has been proposed that allows calculating the parameters of a vortex cooling system for aircraft equipment as functions of flying conditions. The optimum configuration and the dimensions of basic elements of the vortex tube have been determined. By the numerical-modeling method, the operating parameters of the vortex system have been obtained. The adequacy of a computational model has been checked. [ABSTRACT FROM AUTHOR]

Rapid urbanization and unplanned development have posed a threat to the thermal environment in a country like China. The urban heat island (UHI) phenomenon is one of the most serious issues because of its strong relation to thermal comfort, air pollution, and public health. The water bodies, as an important component of the urban ecosystem, are generally considered a vital resource to mitigate the UHI. This study provides direct evidence with the help of satellite observation and field measurement data using the mono-window algorithm, spatial buffer analysis, and linear regression methods to explore how the stream water affects the local temperature variation. The results showed that Land use/cover change (LUCC) and Land surface temperature (LST) on both banks of the Bahe River changed significantly. The LST of the river was significantly massively reduced within the distance range of 300 to 500 m, and 400 to 600 m, with an average temperature dip from 3.7 to 2.8 °C, and from 3.2 to 1.7 °C respectively were during the summer on east and west river banks. In addition, the surrounding LUCC composition and configuration could strongly affect the maximum cooling scale. The results provide insights for urban planners and managers to arrange the LUCC composition between the river design in urban areas and the cooling effect demands. [ABSTRACT FROM AUTHOR]

The development of urban blue-green spaces is highly recommended as a nature-based solution for mitigating the urban heat island phenomenon, improving urban sustainability, and enhancing resident well-being. However, limited attention has been given to the accumulative impact of the cooling effect and the comparison of different types of landscapes. Based on the maximum and accumulative perspectives, this study selected 375 green spaces, water bodies, and urban parks in 25 cities of the Yangtze River Delta (YRD) region in China to quantify their cooling effect. Correlation and regression analyses were employed to identify the dominant factors influencing the cooling performance. The results indicated that (1) compared to other landscape patches, water areas, and parks exhibited a reduction in daily average air temperature by 3.04 and 0.57 °C, respectively. Urban parks provided the largest cooling area (CA) of 56.44 ha in the YRD region, while water bodies demonstrated the highest cooling effect (CE) of 6.88, cooling intensity (CI) of 0.02, and cooling gradient (CG) of 0.99. (2) From the maximum perspective, the perimeter of the patches played a dominant role in CA and CE for all landscape patch types, contributing more than 40% in CA variation. (3) The dominant factors varied among different landscape types from accumulative perspectives. Green spaces were influenced by road density, shape index, and the proportion of water bodies within the CA, whereas water bodies were primarily affected by the coverage of blue spaces. Vegetation growth and densely populated surroundings contributed the most to the cooling of parks. These findings enhanced the comprehension of the cooling effect in comparable urban contexts and provided valuable insights for sustainable urban management. [ABSTRACT FROM AUTHOR]

In this paper, the cooling effect of seawater spraying on the offshore launching platform used by the CZ-8X rocket at different takeoff heights is studied. The rocket plume model using the realizable k- ε turbulence model is established, which is based on the three-dimensional Navier-Stokes equations. The injected seawater for cooling the deck surface is described by the Eulerian dispersed phase (EDP) model. The numerical results are compared with the experimental data in the literature to verify the validity and accuracy of the numerical model. The coupled flow field of the CZ-8X rocket plume and seawater at different takeoff heights and different spray velocities are simulated. The results show that the thermal environment on the deck surface of the platform is the worst when the takeoff height reaches 30 m. The seawater spraying velocity shall be moderate before the takeoff height reaches 30 m. A low spraying velocity will lead to poor cooling effect on deck surface, and a high spraying velocity could lead to increased diffusion of plume flow in non-spraying direction. After the takeoff height rises to 40 m, a low water spraying velocity makes the injection position of seawater far away from the jet core area, and the seawater evaporation rate is low, which is conducive to the accumulation of seawater layer on the deck surface. The cooling effect of thermal barrier layer is very obvious. The research shows that when the rocket is launched at sea, the launch platform can be cooled by pumping and spraying seawater, and the water spraying rate can be adjusted appropriately according to the takeoff height to achieve the best cooling effect. [ABSTRACT FROM AUTHOR]

Thermolectric cooling offers several advantages over conventional refrigeration systems due to its light weight, environmental friendliness, silent operation, and no moving parts. In this work, a thermoelectric water cooling system is created in which water flowing at various flowrates removes heat produced on the hot side of the Peltier module. The cooling effect and coefficient of performance (COP) of the cooling system are experimentally determined at various flowrates of water on the hot side of the module. The cooling effect produced in water increases with the increase in flowrate. A similar trend is noticed for the COP of the system. The maximum cooling effect produced in water is 1363 W at 43 mL/s. The maximum COP of the system is 3.99. [ABSTRACT FROM AUTHOR]

Cornelia Wiegand,1 Ulrike Wesenberg,2 Jan Heggemann3 1Department of Dermatology, Jena University Hospital, Friedrich Schiller University, Jena, Germany; 2Community Hospital Herdecke, Herdecke, Germany; 3Christian Hospital Melle, Niels Stensen Hospitals, Melle, GermanyCorrespondence: Cornelia Wiegand, Department of Dermatology, Jena University Hospital, Am Klinikum 1, Jena, D-07747, Germany, Tel +49 3641 9328878, Fax +49 3641 9328876, Email c.wiegand@med.uni-jena.dePurpose: Chronic wounds are impaired in their healing processes and often require a tissue boost to restart healing progression. Dressings of all forms have been used extensively for decades and a variety of dressings was specifically designed for chronic wounds. A dressing based on a hydropolymer gel matrix with a semi-permeable polyurethane backing is thought to provide an optimal balanced wound moisture environment and could hence positively affect the biochemical composition of exudate. However, the mechanism behind the technology is described sparsely.Patients and Methods: We herein report in vitro data to support the mode of action of the hydropolymer gel dressing concerning fluid management, protease binding and thermal insulation. Moreover, a non-interventional prospective study examined the use of the unique hydropolymer gel dressing on pain levels.Results: Data demonstrated a possible tissue boost by retaining as well as providing fluid, depending on the exudate amount, and by binding proinflammatory proteases. The dressing was further able to stabilize growth factors and provide thermal insulation, thereby positively supporting keratinocyte proliferation and migration in vitro. Furthermore, a significant reduction of the pain level after application could be observed clinically.Conclusion: Together, these factors provide a beneficial environment for wound healing and restarting stagnating wounds (or providing optimal conditions for acute wounds). In addition, the dressing appeared to be a good choice for painful wounds.Keywords: hydrogel, pain relief, cooling effect, thermal insulation, wound healing

During the braking process of a car, the temperature of the brake system increases continuously, and if the cooling performance of the brake system is insufficient, accidents can occur. For this reason, in this study, the experimental method of the Taguchi design was used to optimize the design of a ventilated brake disc with radial vanes using three design parameters (i.e., number of vanes, vane thickness, and steering angle), and the airflow and temperature distribution around the brake disc and tire were simulated using finite elements. The simulation results show that the solution in this study can increase the ventilation gap from 10 to 14 mm, the bending angle of the blades from 29° to 37°, and the cooling effect after emergency braking by 6.1% and 8.8%, respectively, when dissipating heat for 100 s at a driving speed of 60 km/h.

Urban areas with parks tend to have the best outdoor thermal comfort in regions with high urban heat island effects during summer. This study analyzed the synergistic cooling effects of 94 urban parks and the adjacent built-up areas in six districts of Xi’an City using four cooling indicators: park cooling intensity (PCI), park cooling area (PCA), park cooling effect (PCE), and park cooling gradient (PCG). The results showed that 84 out of 94 parks exhibited significant cooling effects, with an average PCI of 1.98 °C, PCA of 51.7 ha, PCE of 6.6, and PCG of 8.2 °C/km. Correlation analyses indicated that the intrinsic park attributes, external buffer zone building height, and building density were the main factors affecting the cooling effect. The park landscape configuration, building height, and density significantly influenced the PCI and PCG, while the park shape and size were crucial for the PCA (positive) and PCE (negative). The optimal park areas for improving the thermal environment were identified as 26 ha (cooling area focus, building density 32%). This study provides theoretical guidance for planning urban parks and the surrounding areas based on cooling effects, offering insights for future climate resilience planning.

Research has demonstrated that urban green spaces play a crucial role in mitigating the severe urban heat island (UHI) effect. However, existing studies often suffer from limitations such as the neglect of the cooling effect of water bodies within the green spaces and incomplete considerations of the overall cooling effect. These limitations may lead to inaccuracies in the research findings. Therefore, the present study takes the city of Xi’an as a case study to explore the optimal green space size for achieving efficient cooling. The results indicate that (i) urban green spaces exhibit robust cooling effects, with variations observed among the various types; (ii) for community parks without water, and for street gardens, the optimal areas of these green spaces are 3.44 and 0.83 hectares, respectively; (iii) for community parks with water, the area of internal water bodies should ideally be maintained at around 29.43% of the total green space area in order to achieve an optimal cooling efficiency. In conclusion, this study introduces a new perspective and new optimization methods for urban green space planning, thereby offering scientific guidance to urban planners in formulating effective development and management policies and urban planning schemes.

Green city areas are crucial in mitigating the Urban Heat Island Effect (UHI). However, the cooling effect of green city areas can be influenced by the surrounding complex urban spatial environment. This study focuses on Changsha, a subtropical city in China, where 40 green city areas were screened and analyzed. The study aims to quantify the specific impact of urban spatial morphology on the cooling effect of green city areas. Through statistical correlation and regression analysis, this study focused on six urban spatial morphology indicators: building density (BD), building floor area ratio (BFR), building volume density (BVD), building evenness index (BEI), building average height (BH), and building height standard deviation (BSD). The results indicate that the cooling effect of green city areas could be influenced by urban spatial morphology. Factors such as BD, BFR, BH, and BSD were found to be significantly correlated with the cooling effect of green city areas, with BH showing the strongest influence. BD and BFR were negatively correlated, while BH and BSD were positively correlated. The range values of BD, BFR, BH, and BSD were determined to achieve the optimal conditions for the cooling effect of green city areas. Additionally, the relative position of the green city areas in the neighboring urban areas affects the cooling effect of the green city areas. The cooling effect is most pronounced in the urban area situated to the south of the green city areas. These findings provide a solid foundation for urban planning around green city spaces and offer scientifically sound evidence for mitigating the UHI.