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Rivers within urban areas could influence the thermal environment by modifying air temperature (AT) and relative humidity (RH). To further explore the cooling effect of a large river on surrounding urban areas, we conducted mobile measurements near the Yangtze River in Wuhan during a hot and humid summer day. This research examined the river cooling effect, determined the thresholds of the cooling and humidifying distance using a third-order polynomial method, assessed littoral heat stress at the pedestrian level and investigated the impact of the littoral built environment using stepwise regression analysis. The results revealed that (1) the cooling and humidifying effect of the river was up to 3.55 °C, 1741 m and 17.25%, 1369 m in the daytime, which was much greater than that at night; (2) the river significantly mitigated pedestrian heat stress within 1200 m from the riverbank in the daytime, but showed a weak negative effect at night; (3) the built environment has a significant impact on the littoral areas, e.g., urban greening during the daytime and building morphology at night. The findings of this study provide empirical evidence for the cooling effect of a large river in urban areas and further support climate-sensitive planning and design for our thermal environment.

Background Periodontitis may result in displacement, overeruption and the tilting of teeth, which can lead to occlusal prematurities and accelerate the loss of periodontal structures. Orthodontic treatment is needed to correct displaced tooth positions, but inappropriate force and tooth movement can lead to further loss of supporting tissues. Aim To describe the treatment of a deep overbite in a 32-year-old male with a history of periodontitis, gingival recession and missing premolars. Methods After evaluation, fixed appliances applying light forces were chosen as the appropriate treatment approach. A segmental arch and a utility arch technique were applied. Periodontal therapy was conducted before and throughout orthodontic care. Results After 28 months of treatment, a normal overbite and overjet were restored. A displaced premolar was repositioned. Space needed for the prosthetic replacement of the missing teeth was obtained and dental implants were planned after orthodontic treatment. The height of the alveolar bone increased in some areas. After 18 months of retention, the attachment level of the upper left incisor increased approximately 1 mm. Conclusion For patients with a compromised periodontium, adequate management of the tissues is the basis of orthodontic care. Appropriate orthodontic treatment may be beneficial to periodontal health in the long term.

Urban waterbodies can effectively mitigate the increasing UHI effects and thus enhance climate resilience of urban areas. To contribute to our limited understanding in cooling effect of waterbodies on surrounding thermal environments, we examine the quantitative relationship between the spatial distribution of urban waterbodies and the land surface temperature (LST) in Wuhan, China. This paper 1) applies two indicators, the fractional water cover and the gravity water index, for measuring the spatial distribution of urban waterbodies; 2) conducts simple linear regression and spatial regression analyses to explore the LST-water relationship at multiple scales; and 3) compares the individual regression results from different land use types. The results show that the spatial distribution of urban waterbodies affects the LST significantly, and the gravity water index sufficiently explains the LST variation at various scales. Furthermore, the impact of urban waterbody distribution on the LST does vary across different land use types. Conclusions from this study provide insights of the cooling effect of urban waterbodies, which can further assist city planners and decision makers in utilizing cooling effects of waterbodies to improve the thermal environment of urban areas.

People's subjective response to any thermal environment is commonly investigated by using rating scales describing the degree of thermal sensation, comfort, and acceptability. Subsequent analyses of results collected in this way rely on the assumption that specific distances between verbal anchors placed on the scale exist and that relationships between verbal anchors from different dimensions that are assessed (e.g. thermal sensation and comfort) do not change. Another inherent assumption is that such scales are independent of the context in which they are used (climate zone, season, etc.). Despite their use worldwide, there is indication that contextual differences influence the way the scales are perceived and therefore question the reliability of the scales’ interpretation. To address this issue, a large international collaborative questionnaire study was conducted in 26 countries, using 21 different languages, which led to a dataset of 8225 questionnaires. Results, analysed by means of robust statistical techniques, revealed that only a subset of the responses are in accordance with the mentioned assumptions. Significant differences appeared between groups of participants in their perception of the scales, both in relation to distances of the anchors and relationships between scales. It was also found that respondents’ interpretations of scales changed with contextual factors, such as climate, season, and language. These findings highlight the need to carefully consider context-dependent factors in interpreting and reporting results from thermal comfort studies or post-occupancy evaluations, as well as to revisit the use of rating scales and the analysis methods used in thermal comfort studies to improve their reliability.My individual contribution: Runa T. Hellwig: Conceptualization, Methodology, Visualization, Writing - Original Draft \ my contribution like all authors Investigation, Writing - Review & Editing, ResourcesInvestigation, Writing - Review & Editing, ResourcesRuna T. Hellwig: Conceptualization,Methodology, Visualization, Writing - Original DraftRuna T. Hellwig: Conceptualization,Methodology, Visualization, Writing - Original DraftRuna T. Hellwig: Conceptualization,Methodology, Visualization, Writing - Original DraftAuthor statementAll authors: Investigation, Writing - Review & Editing, Resources Marcel Schweiker: Conceptualization,Methodology, Visualization, Formal analysis, Writing - Original Draft Rucha Amin: Conceptualization,Methodology Susanne Becker: Conceptualization, Methodology, Writing - Original Draft Joon-Ho Choi:Conceptualization, Methodology Chungyoon Chun: Conceptualization, Methodology Lyrian Daniel:Writing - Original Draft Renata De Vecchi: Writing - Original Draft Stephanie Gauthier:Conceptualization, Methodology, Writing - Original Draft Runa T. Hellwig: Conceptualization,Methodology, Visualization, Writing - Original Draft Gesche M Huebner: Conceptualization,Methodology, Writing - Original Draft Jungsoo Kim: Conceptualization, Methodology Jakub Kolarik:Writing - Original Draft M.C. Jeffrey Lee: Conceptualization, Methodology Karin Schakib-Ekbatan:Conceptualization, Methodology Despoina Teli: Conceptualization, Methodology Conrad Voelker:Writing - Original Draft

Thermal discomfort is one of the main triggers for occupants’ interactions with components of the built environment such as adjustments of thermostats and/or opening windows and strongly related to the energy use in buildings. Understanding causes for thermal (dis-)comfort is crucial for design and operation of any type of building. The assessment of human thermal perception through rating scales, for example in post-occupancy studies, has been applied for several decades; however, long-existing assumptions related to these rating scales had been questioned by several researchers. The aim of this study was to gain deeper knowledge on contextual influences on the interpretation of thermal perception scales and their verbal anchors by survey participants. A questionnaire was designed and consequently applied in 21 language versions. These surveys were conducted in 57 cities in 30 countries resulting in a dataset containing responses from 8225 participants. The database offers potential for further analysis in the areas of building design and operation, psycho-physical relationships between human perception and the built environment, and linguistic analyses., Measurement(s)Natural Language • Demographics • humidity • response to temperature stimulus • temperature of air • geographic location • room temperature ambient airTechnology Type(s)Survey • sensorSample Characteristic - OrganismHomo sapiensSample Characteristic - EnvironmentbuildingSample Characteristic - LocationOman • Kingdom of Spain • Ecuador • Chile • Malaysia • Iraq • Poland • Nigeria • Iran • Italy • United States of America • Germany • Brazil • Jordan • Kingdom of the Netherlands • Greece • Sweden • Kingdom of Denmark • India • Sri Lanka • Uganda • South Korea • Republic of China • United Arab Emirates • Australia • French Republic • United Kingdom • Japan • Indonesia • China Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.9805289

Microclimate knowledge has been intensively integrated into urban planning and design to improve the buildings’ energy performance and outdoor thermal comfort. To assess the climatic mitigation strategies, numerical modeling is gaining higher relevance. ENVI-met, a microclimate model to simulate the complex surface-vegetation-atmosphere interactions in the built environment, is receiving increasing popularity. This study aims to systematically evaluate the thermal-radiative performance of the ENVI-met model based on its recent updates. First, a field measurement was conducted in a subtropical city. Thermal-radiative parameters were collected besides three green infrastructure (GI) typologies (i.e., green roof, green wall, ground tree) and three corresponding reference sites. Second, sensitivity tests were conducted for the inputs and settings of ENVI-met model, including new radiation module IVS (Indexed View Sphere), meteorological boundary conditions, materials settings, and output intervals. Third, the thermal-radiative performance of ENVI-met was compared among the six measurement sites, three output intervals, and nine microclimate variables, based on four evaluation metrics. The results showed that 1) recent updates of ENVI-met can improve the estimation accuracy, especially with IVS on, radiation forcing, and localized materials settings; 2) ENVI-met was capable of simulating the thermal-radiative performance of three GI typologies simultaneously; 3) mobile measurement can be used for ENVI-met validation, and 4) model evaluation results were sensitive to the metrics. Overall, this study emphasized proper validation for ENVI-met before applications, when full forcing and localized settings are essential. The strengths and limitations of ENVI-met were discussed and implications were provided for model developers and users.

Urban heat island (UHI) exerts significant effects on energy consumption and human health. Implementation of green and blue infrastructures can help alleviate urban overheat, especially during warm seasons. However, current studies scarcely considered the heterogeneity of water cooling effect, thus the planning strategies may not be consistent for a variety of situations. This study investigated the water cooling heterogeneity by three main aspects: waterbody, littoral zone, and background climate. The results confirmed the existence of the heterogeneity of water cooling effect, among three lake size groups, six littoral landscapes types and three warm seasons. Firstly, larger lakes presented lower WST (water surface temperature) and higher WCD (water cooling distance) than smaller lakes. Secondly, the Compact lowrise showed the highest mean temperature and lowest cooling distance in littoral areas among six landscapes. Threshold value of efficiency (TVoE) of WCD was much higher than that of WCI. Thirdly, summer period presented the greatest average WCI (water cooling intensity) for all lakes size groups, while spring had the highest average WCD for large and medium lakes. Given the revealed heterogeneity of water cooling effect in three aspects, this study proposed some specific strategies in urban planning for cooler cities.

The re-integration of trees into the urban landscape is a veritable strategy for urban climate mitigation and adaptation. However, dysfunctional trees in terms of urban heat mitigation are dominant in many sub-tropical cities' landscapes due to the lack of scientific basis of tree selection. Therefore, this study proposes and evaluates a methodological framework as an approach for “right tree, right place” for urban heat mitigation through parametric ENVI-met simulations that involve the combination of 54 generic tree forms and 10 characteristic urban morphology – Sky-View Factor (SVF). Results show variable temperature regulation by tree forms (species) with varying magnitude in different urban morphology. Daytime and nighttime temperature regulation effects were between 0.3 °C – 1.0 °C and 0.0 °C – 2.0 °C, respectively depending on tree forms and SVF value. Furthermore, the Heat Reduction Potential (HRP) of trees forms were determined in terms of their human thermal comfort improvement. In general, we found a range of +5% and − 20% depending on SVF, negative and positive values imply heat reduction and increment, respectively. With the competing shading effect of buildings, the HRP of trees reduces from high to low SVF area with variable magnitude among tree forms (species). Hence, the proposed morphology-based tree selection approach was evaluated by comparison with two uninformed selection approaches in a realistic urban neighborhood in Hong Kong. Results clearly indicate the proposed approach's capability in improving human thermal comfort by up two times more than either of the other approaches. Finally, evidence-based recommendations were given for the reference of policy-makers when they make urban green development plan.

Urban greenery, especially trees, has been proven to be one of the effective measures for urban heat island mitigation. However, no consistent findings have been found for the relationship between greenery abundance and cooling magnitude; while some previous studies discovered a linear relationship, others opined it could a non-linear one. In addition, there are rare studies exploring whether or not the strength of the relationship is dependent on urban density. Therefore, in this study, we aim to discuss cooling efficiency by measuring the relationship between greenery coverage ratio and the cooling effects of greenery. Parametric studies were conducted in a validated ENVI-met model, with different combinations of urban densities (Low, Mid, and High) and tree coverage ratios (2–30% at 2% interval, and 56% for full area coverage other than building). Then the pattern of the cooling efficiency was explored under three urban densities scenarios and two selected temporal periods on a typical summer daytime. For a subtropical climate background, results showed a non-linear (logarithmic) pattern for tree coverage ratio (TCR) and cooling effects, irrespective of the urban density, temporal periods, and heat indicators. When TCR reached 20–30%, the optimal cooling efficiency of trees were achieved, irrespective of building densities and temporal periods. The optimal threshold for greenery coverage in this study can provide science-based suggestions to urban planners and designers for better microclimate and thermal comfort environments at the neighborhood scale.

Improving urban heat environment and air quality by altering urban wind paths is a rising topic in PSS, but it currently lacks quantitative methods and practical framework. This study proposes a systematic approach to supporting urban wind path planning for improving heat environment, using remote sensing images and wind and temperature data from local weather stations, GIS-based building and road data, etc. Local surface urban heat islands (LSUHIs) are identified by retrieving remote sensing data, the knowledge of which is combined with other local knowledge to determine target regions for heat environment improvement. Potential wind paths are determined by natural wind resources and built-up environment: Macroscopic simulation of the city’s wind field with WRF model localizes and quantifies natural wind resources; building density, surface roughness, and road orientation describe morphological factors that influence local ventilation capabilities, including its coherence with and resistance against potential natural winds. With the problematic regions and potential wind paths thus delineated, planning measures can then be correspondingly formulated.

Facing urban warming, mitigation and adaptation strategies are not efficient enough to tackle excessive urban heat, especially at the local scale. The local climate zone (LCZ) classification scheme is employed to examine the diversity and complexity of the climate response within a city. This study suggests that zonal practice could be an efficient way to bridge the knowledge gap between climate research and urban planning. Urban surfaces classified by LCZ are designated as urban climate landscapes, which extends the LCZ concept to urban planning applications. Selecting Wuhan as a case study, we attempt to explore the climatic effect of landscape patterns. Thermal effects are compared across the urban climate landscapes, and the relationships between patch metrics and land surface temperature (LST) are quantified. Results indicate that climate landscape layout is a considerable factor impacting local urban climate. For Wuhan, 500 m is an optimal scale for exploring landscape pattern-temperature relationships. Temperature contrast between surrounding landscape patches has a major influence on LST. Generally, fragmental landscape patches contribute to heat release. For most climate landscape types, patch metrics also have a significant effect on thermal response. When three metrics are included as predictive variables, 53.3% of the heating intensity variation can be explained for the Large Lowrise landscape, while 57.4% of the cooling intensity variation can be explained for the Water landscape. Therefore, this article claims that land-based layout optimization strategy at local scale, which conforms to planning manner, should be taken into account in terms of heat management.

Urban greenery especially trees has been identified as one of the most effective measures for urban climate moderation through the mechanism of evaporative cooling and shading. For subtropical high-density cities like Hong Kong, intense heat stress arises from the compact urban form, poor ventilation, and the high percentage of impervious urban cover. Thus, concerted actions are being taken to harness the cooling potential of urban greenery for improved microclimate. However, the cooling effects of urban greenery vary based on multiple factors, including background climates, urban morphology, anthropogenic heat emission, vegetation types and quantity, etc. This study aims at quantifying and comparing the cooling efficiency of different urban greenery coverage for a typical residential neighbourhood in Hong Kong. The questions guiding our research are: what is the relationship between tree coverage and ambient environment, including air temperature and thermal comfort during a typical summer day in the selected neighbourhood? To achieve this objective, we employed a previously validated ENVImet model setting of a typical summer day to conducted parametric studies of cooling benefit of variable tree coverage ratio from 0 to 30% at the interval of 2% on a typical summer day. The results verified the greenery had a higher cooling potential during period of maximum temperature than the whole diurnal time, 1 °C and almost 0.8 °C respectively for air temperature. This study also showed that increasing greenery coverage indeed lowers diurnal temperatures, but this relationship is logarithmic instead of linear. The ratio of change in cooling effects to greenery increase and then decreased gradually. Between the coverage ratio of 8%-35%, the cooling potential would be underestimated in a linear relationship. Greenery measures may lead to ineffective results if greening principles have not been comprehensive understood, such as greenery abundance, composition and types. The present study allows urban planners and managers to understand more in greenery amount for urban micro-climate in high-density cities.