Search Results (22)

With rapid advancements in industrialization and urbanization, Beijing is increasingly facing severe urban heat island effects and air pollution, particularly from haze. Urban parks play a vital role in improving the local microclimate and facilitating the dispersion of fine particulate matter (PM_2.5). However, most existing studies have focused primarily on the cooling and humidifying functions of urban parks, with limited attention given to the combined assessment of their regulatory effects on both the microclimate and air pollutants. Moreover, the influence of seasonal variation on these ecological services has rarely been systematically examined. To address these research gaps, this study selected three representative urban parks in Beijing and conducted a quantitative analysis of four key environmental parameters—air temperature, relative humidity, wind speed, and PM_2.5 concentration—during spring, summer, and winter. Using Landsat remote sensing imagery and the ENVI-met v3.1 computational fluid dynamics (CFD) model, this study simulated dynamic changes in the microclimate and pollutant dispersion within parks. Model feasibility was evaluated through validation metrics and comparisons with field observations. The results show the following: (1) Urban parks significantly improve the local microclimate and reduce PM_2.5 concentrations, with the most notable effects observed in summer when the ecological functions of vegetation are at their peak. (2) The ENVI-met model can be used to simulate the microclimate and PM_2.5 dispersion in the three parks, with the highest simulation accuracy occurring during the summer season. This study provides valuable insights for urban park planning in Beijing, particularly for developing strategies to enhance microclimatic conditions and mitigate air pollution. Full article

Preserving historical porous materials requires careful monitoring of surface humidity to mitigate deterioration processes like salt crystallization, mold growth, and material decay. While microclimate monitoring is a recognized preventive conservation tool, its role in detecting surface-specific moisture risks remains underexplored. This study evaluates the relationship between indoor microclimate fluctuations and surface moisture dynamics across 13 historical sites in Northern Italy (Lake Como, Valtellina, Valposchiavo), encompassing diverse masonry typologies and environmental conditions. High-resolution sensors recorded temperature and relative humidity for a minimum of 13 months, and eight indicators—including dew point depression, critical temperature–humidity zones, and damp effect indices—were analyzed to assess the moisture risks. The results demonstrate that multivariate microclimate data could effectively predict humidity accumulation. The key findings reveal the impact of seasonal ventilation, thermal inertia, and localized air stagnation on moisture distribution, with unheated alpine sites showing the highest condensation risk. The study highlights the need for integrated monitoring approaches, combining dew point analysis, mixing ratio stability, and buffering performance, to enable early risk detection and targeted conservation strategies. These insights bridge the gap between environmental monitoring and surface moisture diagnostics in porous heritage materials. Full article

Low-cost air temperature sensors are an emerging theme in environmental monitoring. These sensors offer the advantage of making microclimate monitoring feasible due to their affordability. However, they are limited by the quality of the data they provide; in many cases, they have been reported to have presented errors in the sensor readings. These errors have been shown to improve after calibration was applied. The lack of a comprehensive understanding of the available calibration techniques, models, and sensor types has led to studies presenting heterogeneity in models and techniques alongside different performance metrics. To address this gap, this study conducted a systematic review following the PRISMA guidelines, reviewing studies from 2015 to 2024 across the databases Web of Science and Scopus, alongside the search engine Google Scholar. The aim was to identify the calibration techniques and models, the commercially available low-cost air temperature sensors used, the performance metrics utilised, and the calibration settings. The findings presented three main categories of calibration models utilised in the collected studies: linear, polynomial, and machine learning. Twenty-two commercially available low-cost sensors were identified, with the DHT22 sensor being the most utilised. Indoor settings were identified as the most preferred for conducting calibrations. Key challenges included limitations in reported results for calibration by the studies, the use of different performance metrics across studies, insufficient studies conducting calibration, and the diversity in sensor types utilised. Full article

Current building energy modeling (BEM) tools lack the capability to inherently simulate the impacts of urban microclimates on building energy performance. While efforts have been made to integrate BEM with Urban Microclimate Modeling (UMM) tools, their ability to capture spatial and seasonal microclimate variations remains limited. This review critically evaluates existing urban microclimate-integrated BEM approaches and their effectiveness in modeling the complex interactions between urban form, microclimate, and building energy performance. Through an analysis of 94 research articles, the review first examines the influence of urban form on microclimates, followed by an assessment of how microclimatic conditions impact building energy use. Additionally, it evaluates conventional modeling frameworks employed in BEM tools and their limitations in representing dynamic microclimatic variations. The findings emphasize the non-linear heat exchange relationships between urban form and microclimate, typically modeled using computationally intensive Computational Fluid Dynamics (CFD)-based UMM tools. This review introduces a classification of heat exchange types: atmospheric heat exchange, involving air temperature, wind, and humidity, and non-atmospheric heat exchange, driven by radiative interactions with surrounding urban surfaces. The study further highlights that modifying standard weather files and heat transfer coefficients alone is insufficient for BEM tools to accurately capture near-surface microclimate variations. By identifying critical insights and research gaps, this review establishes a foundation for advancing next-generation urban microclimate-integrated BEM approaches, emphasizing the need for computationally efficient and dynamically responsive modeling techniques. Full article

The self-contained breathing apparatus (SCBA) is an integral part of the structural firefighting personal protective equipment (PPE) ensemble. However, when donned, it adds significant weight and restriction, interfering with the fit of the turnout suit and the ventilation within the clothing system. This may result in a reduction of air gaps within the clothing microclimate, quickening the onset of heat strain. Therefore, the purpose of this study was to assess the impact of the SCBA on air gaps in structural firefighting turnout suits. Nine active-duty male firefighter participants were scanned in a three-dimensional body scanner in four garment configurations (compression, base layers, turnout suit, and turnout with SCBA). Torso volume, surface area, and air gaps were calculated alongside ease measurements. Findings demonstrated a 59% increase in torso volume when donning the turnout suit over base layers compared to a 1.2% reduction in torso volume when donning the SCBA. The change in torso air gap volume and distance were also found to be negligible when donning the SCBA. This study lays the foundation for full systems ensemble research needed to better understand how the design, weight, and fit of the SCBA impacts the thermal comfort, mobility, and protection of structural firefighters. Full article

This paper introduces a methodology aimed at bridging the gap between building energy simulation and urban climate modeling. A coupling method was developed through the Building Control Virtual Test Bed (BCVTB) and applied to a case study in Taipei City, Taiwan, to address the microclimate factors of street trees crucial to cooling energy consumption. The use of the Urban Weather Generator for weather file modification revealed a 0.63 °C average air temperature disparity. The coupling method emphasized the importance of accurate wind speed and convective heat transfer coefficients (CHTCs) on building surfaces in determining cooling energy. The results indicated that elevated CHTC values amplify heat exchange, with higher wind velocities playing a crucial role in heat dissipation. The presence of street trees was found to significantly reduce heat flux penetration, leading to a reduction in building surface temperatures by as much as 9.5% during hot months. The cooling energy was lowered by 16.7% in the BCVTB simulations that included trees compared to those without trees. The EnergyPlus-only simulations underestimated the cooling energy needs by approximately 9.3% during summer months. This research offers valuable insights into the complex interactions between buildings and their environments. The results highlight the importance of trees and shading in mitigating the heat island effect and improving energy-efficient urban planning. Full article

In response to the challenge of atmospheric pollution posed by growing environmental problems, this study reviews and analyzes the research status and development trends of green infrastructure (GI) in improving air pollution from 2014 to 2024. Using the CiteSpace tool, we explore research hotspots, disciplinary developments, significant contributors, and influential literature in this field, identifying current research gaps and predicting future trends. The findings indicate that GI significantly impacts the reduction of air pollution, the regulation of urban microclimates, and the enhancement of ecosystem services. However, existing studies often focus on isolated aspects and lack comprehensive assessments. Moreover, the research trajectory in this field shows a declining trend. Future research should emphasize interdisciplinary integration, combining ecology, urban planning, meteorology, and public health. By utilizing advanced technologies, such as drones, remote sensing, AI, and big data analysis, we can improve data accuracy and the generalizability of research findings. Additionally, it is crucial to consider the performance of GI under different climatic conditions and socio-economic contexts to comprehensively quantify its overall benefits in terms of air quality, urban thermal comfort, public health, and economic impact. This comprehensive approach will provide a scientific basis for policy-making and urban planning. Full article

Numerous studies have examined the impact of urban form on microclimate and thermal comfort at street level. However, the relationship between air pollution concentration and urban form, particularly vegetation and building arrangement, is less considered among planners and designers, and not many case study examples are available in the literature. To address this gap, this paper provides additional evidence and a case study example, illustrating the impact of the built environment on air pollution in urban areas. The Golden Lane Estate, a residential development that has valuable and repeatable urban design and architectural features and is located near a highly congested and polluted area in central London, was selected as the study site. The analysis involved a combination of fieldwork spot measurements and computational modelling (ENVI-met), considering physical features of urban blocks, levels of air pollution, and meteorological parameters (using data from local meteorological stations). The site modelling simulated current conditions and a condition without vegetation to better understand the impact of vegetation on pollutant concentration. The results indicate that urban form and vegetation arrangements significantly affect wind speed and direction, exacerbating air pollution within street canyons of varying aspect ratios. Such findings contribute to the expanding field of hyperlocal scale measurement and underscore the need for guidelines regarding the optimal placement, scale, type, and distribution of vegetation within street canyons. Full article

Elevated face temperature due to mask wearing can cause discomfort and skin irritation, making mask mandates challenging. When thermal discomfort becomes intolerable, individuals instinctively or unknowingly loosen or remove their facemasks, compromising the mask’s protective efficacy. The objective of this study was to numerically quantify the microclimate under the mask and facial thermoregulation when wearing a surgical mask with different levels of misfit. An integrated ambient–mask–face–airway computational model was developed with gaps of varying sizes and locations and was validated against complementary experiments. The low Reynolds number (LRN) k-ω turbulence model with porous media was used to simulate transient respiratory flows. Both skin convective heat transfer and tissue heat generation were considered in thermoregulation under the facemask, besides the warm air exhaled from the body and the cool air inhaled from the ambient. The results of this study showed that when wearing a surgical mask with a perfect fit under normal breathing, the temperature at the philtrum increased by 4.3 °C compared to not wearing a mask. A small gap measuring 0.51 cm² (gap A) at the nose top resulted in 5.6% leakage but reduced the warming effect by 28% compared to zero gap. Meanwhile, a gap of 4.3 cm² (R1L1) caused 42% leakage and a 62% reduction in the warming effect. Unique temporospatial temperature profiles were observed at various sampling points and for different gap sizes, which correlated reasonably with the corresponding flow dynamics, particularly close to the gaps. The temperature change rate also exhibited patterns unique to the gap site and sampling point, with distinctive peaks occurring during the inspiratory–expiratory flow transitions. These results have the significant implications that by using the temporospatial temperature profiles at several landmark points, the gap location can potentially be pinpointed, and the gap size and leakage fractions can be quantified. Full article

As the effects of climate change and urbanisation intensify, liveability and comfort in outdoor spaces decrease. Because of large spaces exposed to solar radiation and low crossing of airflows, courtyard buildings are extremely vulnerable in this regard. However, there are significant gaps in the literature on outdoor comfort in courtyards, especially regarding the effect of border configuration (including gap position and features), as well that of tree density. The study proposes a methodology—to be used during preliminary design—to compare the effect of alternative scenarios for courtyard buildings on outdoor microclimate, varying both the building perimeter configuration and courtyard vegetation layout. A matrix is set to combine the two variables and select relevant scenarios, which are then simulated in ENVI-met focusing on air temperature, wind speed and physiological equivalent temperature (PET). A case study in Bologna, Italy (humid subtropical climate) is presented as an example of the implementation. The resulting outdoor microclimate maps and frequency diagrams are compared and discussed. It emerges that both variables have a role in outdoor comfort: while gap configuration affects air temperature more (up to a difference of 1 °C), tree density impacts PET by up to 2 °C difference. The methodology can be replicated in several other contexts to support the optimisation of courtyard building design from the early stages. Full article

Thermophysiological comfort is a crucial aspect of human life, contributing to health and work performance. The current paper aims to enhance the understanding of current research, progress, and remaining challenges regarding clothing thermophysiological comfort from a textile science perspective. It provides a comprehensive review of several facets of clothing thermophysiological comfort, focusing on the history of thermophysiological comfort prediction models, heat and moisture transfer mechanisms in the skin–clothing–environment system, controlling factors of thermophysiological comfort, textile materials for superior thermophysiological comfort, and thermal comfort assessment techniques. The paper shows that previously developed thermophysiological comfort models were mainly based on the human thermoregulation process. However, the effect of the air gap size between the human skin and the cloth layer, i.e., the microclimate, on the heat and moisture transfer in the skin–clothing–environment system has been largely overlooked. In addition, thermophysiological comfort models of skin–clothing–environment systems generally only considered dry thermal resistance and evaporative resistance, yet many other fabric properties have effects on human thermophysiological comfort. Potential future directions are identified to fill some of the current gaps. A conceptual model of clothing comfort to contribute to a better understanding of thermophysiological comfort is also proposed. Full article

Land–atmosphere interactions are influenced by the earth’s complex underlying subsurface, which in turn indirectly affects atmospheric motion and climate change. Human activities are increasingly exerting an influence on desert ecosystems, and artificial green land with clear functional orientation has been established in many desert areas. Consequently, the previously dominant, shifting, sand-covered, underlying surface in these desert regions is gradually transforming. This transformation has significant implications for the characteristics of land–atmosphere interactions, causing them to deviate from their original state. At present, existing studies still have not presented a systematic understanding of this change and have ignored the impact of human activities on land–atmosphere interactions in artificial green land. To address these research gaps, this study specifically targets artificial green land in the Tazhong region of Taklamakan Desert. We carried out observation experiments on land–atmosphere interactions in three different functional units from outside to inside: natural shifting sands, the shelter forest, and the living area. We also analyzed the differences and attribution of land–atmosphere interactions characteristics of different functional units. Compared with the natural shifting sands, the daily average maximum values of wind speed in the shelter forest decreased by 78%, and the daily average maximum air temperature and soil (0 cm) temperature decreased by 2.6 °C and 7 °C, respectively. Additionally, the soil moisture level was significantly increased throughout the green land due to the shelter forest. The surface albedo experienced a decrease, with an annual average of 0.21. Furthermore, the aerodynamic roughness and bulk transport coefficient increased by two orders of magnitude. The daily average maximum values of sensible heat flux and soil heat flux (G₀₅) decreased by 18.7% and 75%, respectively, and the daily average maximum value of latent heat flux increased by 70.3%. This effectively improved the microclimate environment of the green land. The living area was greatly reduced by the shelter forest coverage and influenced by the buildings. Consequently, the environmental improvement was not as large as it was inside the shelter forest. However, it still provided a good shelter for production and living in the desert area. Throughout the year, a total of 4.60 × 10⁵ t water was consumed through evapotranspiration in the artificial green land. The findings of this study have the potential to enhance our comprehension of land–atmosphere interactions in desert regions, thereby offering valuable insights for the establishment and effective management of artificial desert green lands. Full article

Precise meanings of thermophysical processes taking place in air gaps have decisive importance in composite cladding structure systems’ calculation and modeling. The climatic load conditions in Kazakhstan can significantly affect the microclimate of premises in general. In this work, a review study is carried out to obtain the relevant scientific literature on enclosing structures with air gaps under various climatic conditions. The review mainly covers research institutes from Sweden, Norway, France, Saudi Arabia, Russia, and China. On the issue of the air gap parameter’s influence on thermophysical processes, 16 papers were analyzed, and on the issue of air infiltration, 12 papers were analyzed. However, the review shows a lack of research in this area under various climatic conditions. At the same time, experience has shown that the principle of multilayer protection from climatic influences creates a favorable microclimate in buildings, but due to a possible temperature drop, wall structures made of composite building materials can be quite favorable under some conditions, and under others they may be less favorable. Therefore, working out a new energy-saving design with air gaps for climatic conditions with large temperature fluctuations during summer and winter is an urgent task. Full article

The rock bed heating system is a more cost-effective concept for storing thermal energy use in greenhouses at night during the cold winter season. This system is considered an environmentally friendly solution compared to conventional heating systems that rely on fossil fuels. Despite the abundance of research on thermal energy-based heating systems, only limited work on climate modeling in greenhouses using rock bed heat storage systems has been reported. To fill this research gap, this study aims to simulate the microclimate in a greenhouse equipped with a rock bed heating system using computational fluid dynamics (CFD) models. User-defined functions have been implemented to account for the interactions between the plants and the air within the greenhouse. Crop rows and rock bed blocks have been considered as porous media with their dynamic and thermal proprieties. The model’s accuracy was approved by comparing simulated and experimental climate parameter data from the greenhouse. The model’s ability to predict temperature, humidity, and air velocity fields in the greenhouse as well as in the rock bed system during both phases of energy storage and restitution was demonstrated. The thermal, dynamic, and hygric fields were accurately replicated with this numerical model. The growing zone had a vertical temperature gradient between the ground and the greenhouse roof, as well as high humidity. The distribution of temperature fields along the rock bed blocks showed a significant temperature gradient between the air inlet and outlet in the blocks during the two phases of heat storage and restitution. As a result, the model could be useful for sensitivity studies to improve the performance of this thermal storage heating system. Full article

Agroforestry is one nature-based solution that holds significant potential for improving the sustainability and resilience of agricultural systems. Quantifying these benefits is challenging in agroforestry systems, largely due to landscape complexity and the diversity of management approaches. Digital tools designed for agroforestry typically focus on timber and crop production, and not the broader range of benefits usually considered in assessments of ecosystem services and natural capital. The objectives of this review were to identify and evaluate digital tools that quantify natural capital benefits across eight themes applicable to agroforestry systems: timber production and carbon sequestration, agricultural production, microclimate, air quality, water management, biodiversity, pollination, and amenity. We identified and evaluated 63 tools, 9 of which were assessed in further detail using Australia as a case study. No single tool was best suited to quantify benefits across each theme, suggesting that multiple tools or models could be combined to address capability gaps. We find that model complexity, incorporation of spatial processes, accessibility, regional applicability, development speed and interoperability present significant challenges for the tools that were evaluated. We recommend that these challenges be considered as opportunities to develop new, and build upon existing, tools to enhance decision support in agroforestry systems. Full article