Assessing the spatial heterogeneous impacts of urban heat island effects on active travel by leveraging social media data

Adolescent active travel and physical activity: Role of social media, norms and the environment

Impact of an Australian state-wide active travel campaign targeting primary schools

Purpose Active travel (AT) incorporates physical activity into daily living, critical for healthy adolescent development. We explore adolescent and parent attitudes and behaviours related to motivations for adolescent AT and effects of the COVID-19 pandemic. Methods We conducted semi-structured Zoom interviews with 25 adolescent-parent dyads in communities across Israel during early stages of the COVID-19 pandemic. Thematic content analysis was used to develop categories and themes. Results We identified key themes related to adolescent AT: Fostering independence enables adolescent AT; Pampering and safety concerns inhibit adolescent AT; Family and community norms influence adolescent travel modes; Personal enjoyment and positive attitudes facilitate AT; Peers and social networks promote adolescent AT and PA; Built environment and transport options influence AT choices. Interestingly, adolescents indicate AT is an opportunity for peer-to-peer communication without screen distraction, yet they use social media to promote AT and PA. Conclusions The findings point to the influence of positive parent perceptions, active and supportive family and community norms on adolescent AT. Peer norms and social networks as well as features of the built environment also have the potential to influence AT. The COVID-19 pandemic encouraged use of AT and provided a setting for positive AT experiences.

Context: Promoting regular physical activity can be challenging. Active travel (AT), walking and biking for transportation, is a way to achieve more activity, but rates remain low in the United States. With increased technology use, social media is one way to expand reach. Objective: The purpose of this study was to describe the reach of social media in a campaign to promote AT to a university campus. Design: This was an observational study. Setting: The Active Lions campaign promoted AT to and on a large university campus for employees and students. The campaign included local events promoting AT, a smartphone app, and social media postings (Facebook, Twitter) from August 2014 to August 2015. Main Outcome Measures: The social media postings included different types of messages about AT. These posts were then examined and categorized, and any responses or interactions were recorded to identify trends for engagement. Results: The Facebook page had 177 followers, educational posts elicited the most responses, posts with pictures averaged 6 clicks and 1 like, and posts with links averaged 3 clicks and 1 like. Active Lions had 103 Twitter followers, educational posts on Twitter had the most activity, with 149 interactions. Conclusion: Facebook and Twitter appear to reach some of their followers in motivating and promoting regular physical activity. It is important, however, to recognize that posting on social media targets the younger population. Therefore, to reach more adults, it may be more beneficial to find other tactics to promote regular physical activity.

Active travel (AT) has the potential to integrate with, or in some cases substitute for, trips taken by motorized transportation. In this paper we review relevant research on AT outcomes to address the potential of AT and emerging data sources in supporting the transport paradigm shift toward AT. Our analysis identifies physical, mental, built and physical environmental, monetary, and societal outcomes. Traditional methods used to acquire AT data can be divided into manual methods that require substantial user input and automated methods that can be employed for a lengthier period and are more resilient to inclement weather. Due to the proliferation of information and communication technology, emerging data sources are prevailing and can be grouped into social fitness networks, in-house developed apps, participatory mapping, imagery, bike sharing systems, social media, and other types. We assess the emerging data sources in terms of their applications and potential limitations. Furthermore, we identify developing policies and interventions, the potential of imagery, focusing on non-cycling modes and addressing data biases. Finally, we discuss the challenges of data ownership within emerging AT data and the corresponding directions for future work.

Physical activity (PA), including active travel (AT), is related to healthy adolescent development and wellbeing, however, behavior rates are low. Simultaneously, adolescent screen use, and engagement in social media platforms (SMP) is very high. The aim of this mixed methods study was to explore the relationship between peer engagement and SMP and adolescent AT and PA. We employed an exploratory sequential design that included integration of results of qualitative interviews with 25 adolescent-parent dyads and quantitative data from a cross-sectional survey in a representative sample of Hebrew-speaking adolescents in secondary schools across Israel ( n = 2,911). Reflexive thematic analysis was employed for the qualitative study; constructs identified served as the basis for development of a quantitative data collection instrument. Correlation and linear regression analyses were conducted to investigate associations between key quantitative analysis variables. The integrated analysis primarily identified convergence between datasets expressed in narrative weaving and joint displays. We found that AT with peers is a social activity; AT and PA are an opportunity for peer-to-peer communication without screens; and SMP are utilized to promote AT and PA. Interventions that emphasize these key constructs as well as use of SMP may increase adolescent AT and PA behaviors.

In the tourism sector, social media data help elucidate the travel behavior and activities of travelers through images and reviews. However, geospatial studies with spatial analysis tools such as GIS are still required by researchers who hope to gain beneficial insight into tourism development from such social media data. In addition to spatial studies, Space syntax analysis is used to explain the spatial characteristics and accessibility of both pedestrians and vehicles; however, the method doesn't consider how people use the space. Therefore, using social media with space syntax analysis will help enhance the understanding of both tourism and spatial aspects. This research aims to develop analytical tools to support tourism studies with the GIS (graphic information system) process using social media data analysis and spatial morphological results from space syntax analysis. The study found that the accessibility potential of a destination does not enhance the popularity of tourist attractions as much as relevant images or attractions due to many popular tourist attractions being located in areas with low potential accessibility. While the image processing and text processing results can extract hidden traits and identities in each attraction, another result is that the analytical tool developed in the study can help quantify tourism activities and perform preliminary content analysis of the data from text and Image processing through the GIS software. It is also used to overlay tourism activities and spatial morphology results in order to recognize the tourism development potential of the area in terms of destination image tourism activities and accessibilities. The tool produces useful results and assists in decision-making for the development of tourist attractions.

Exploring the spatial heterogeneity of urban heat island effect and its relationship to block morphology with the geographically weighted regression model

Urban heat island effect: A systematic review of spatio-temporal factors, data, methods, and mitigation measures

BackgroundThe explosive growth of social media has rendered them powerful communication channels. User generated content is an important source of inspiration and influence among web friends, it generates new activities and consequently affects mobility decisions. Whether to visit a place, or how to get to a place of interest are decisions that can be triggered through people’s interactions on social media.ObjectiveThe main objective of this paper is to investigate the influence of social media use on activity planning and travel arrangements for women and men.MethodsAn online survey was conducted to examine the social media use and the impact of the shared content for women and men, on the phase before any activity in an urban environment. Inferential statistics were applied to detect gender differences in a sample size comprised of 804 respondents.ResultThe significant results showed that the variables gender and social media use for activity planning and travel arrangements are associated with each other. Results have also indicated that the influence of reviews and ratings, photos/ videos and proposed transport mode on activity planning is gender dependent. Photos/ videos influence more often both women (m=3.47) and men (m=3.00) than reviews and ratings (m=3.21 for women and 2.94 for men). Both these contents influence more than proposed transport mode (m=2.62 and 2.37 for women and men).ConclusionThe analysis of the results indicated that before an activity, both women and men tend to use majorly social media for activity planning and travel arrangements, while photos/videos influence women’s decisions more often than men.Travel arrangements of the majority of respondents would be influenced by a post of a designated account related to transport. Finally, social media use affects travel arrangements of both women and men more before performing an activity rather than during.

Abstract. Along with urbanization, sealing of vegetated land and evaporation surfaces by impermeable materials, lead to changes in urban climate. This phenomenon is observed as temperatures several degrees higher in densely urbanized areas compared to the rural land at the urban fringe particularly at nights, so-called Urban Heat Island. Urban Heat Island (UHI) effect is related with urban form, pattern and building materials so far as it is associated with meteorological conditions, air pollution, excess heat from cooling. UHI effect has negative influences on human health, as well as other environmental problems such as higher energy demand, air pollution, and water shortage. Urban Heat Island (UHI) effect has long been studied by observations of air temperature from thermometers. However, with the advent and proliferation of remote sensing technology, synoptic coverage and better representations of spatial variation of surface temperature became possible. This has opened new avenues for the observation capabilities and research of UHIs. In this study, "UHI effect and its relation to factors that cause it" is explored for İzmit city which has been subject to excess urbanization and industrialization during the past decades. Spatial distribution and variation of UHI effect in İzmit is analysed using Landsat 8 and ASTER day & night images of 2015 summer. Surface temperature data derived from thermal bands of the images were analysed for UHI effect. Higher temperatures were classified into 4 grades of UHIs and mapped both for day and night. Inadequate urban form, pattern, density, high buildings and paved surfaces at the expanse of soil ground and vegetation cover are the main factors that cause microclimates giving rise to spatial variations in temperatures across cities. These factors quantified as land surface/cover parameters for the study include vegetation index (NDVI), imperviousness (NDISI), albedo, solar insolation, Sky View Factor (SVF), building envelope, distance to sea, and traffic space density. These parameters that cause variation in intra-city temperatures were evaluated for their relationship with different grades of UHIs. Zonal statistics of UHI classes and variations in average value of parameters were interpreted. The outcomes that highlight local temperature peaks are proposed to the attention of the decision makers for mitigation of Urban Heat Island effect in the city at local and neighbourhood scale.

Various cities in China have been identified as “stove cities” either in contemporary or historical times, exposing residents to extremely high temperatures. Existing studies on the heat island effect in stove cities are not representative nationwide. The outdated nature of these studies also significantly diminishes the relevance of their findings. Thus, reassessing the urban heat island (UHI) effect of stove cities is necessary in the context of global climate change and urbanization. This study focuses on seven symbolic and geographically distributed stove cities in China, including Nanjing, Chongqing, Wuhan, Fuzhou, Beijing, Xi’an, and Turpan. Using land surface temperature (LST) data, this study investigates the summer heat island effect from 2013 to 2023 and analyzes changes in the spatial distribution of the heat island effect. This paper utilizes impervious surface data and urban clustering algorithms to define urban and suburban areas. It then examines the evolution and spatial distribution of surface urban heat island intensity (SUHII) over time. Incorporating urbanization variables like population density and urban area, the study analyzes the main factors affecting the heat island effect from 2013 to 2018. We find that all cities continuously expand, with the annual average heat island effect intensifying over the years. With the exception of Beijing, the summer heat island or cool island effects in the remaining six cities show an overall intensification trend. From 2013 to 2018, SUHII has been primarily related to urban expansion and planning layout, with minimal impact from factors such as population density.

Author index for volume 233

Green buildings are an important constituent part of the urban ecosystem; they act as an adjuster of temperature and humidity of the environment in cities, and can effectively alleviate the Urban Heat Island (UHI) effect. Existing studies on the UHI effect generally ignored the local information in the changes of the UHI effect, and the impact of the optimization of green building distribution on the UHI effect hadn’t been taken into consideration. To fill in this research gap, this paper aims to study the optimization of the distribution of green buildings based on the UHI effect. At first, this paper adopted a high-precision radiative transfer model to invert the temperature of earth surface in cities, and accurately calculate the UHI effect. Then, this paper analyzed the changes in the UHI effect caused by the optimization of the distribution of green buildings and the response of human activities, and used the time variation law of the single pixels of green buildings to reflect the spatial variation law of the UHI effect. At last, experimental results gave the optimization results of the distribution of green buildings based on the UHI effect.

An afternoon heavy rainfall event occurred over coastal Nantong, an area of 70–100 km downstream from the Shanghai–Suzhou–Wuxi–Changzhou city belt over the Yangtze River Delta, under the influences of weak southwesterly monsoonal flows and lake/sea breezes on 26 July 2018. An observational analysis shows the emergence of pronounced urban heat island (UHI) effects along the city belt during the late morning hours. A series of nested-grid cloud-permitting model simulations with the finest grid spacing of 1 km are performed to examine the impacts of urbanization on convection initiation (CI) and the subsequent heavy rainfall event. Results reveal the generation of lake breezes and warm anomalies in the planetary boundary layer along the city belt and low-level convergence, thereby inducing upward motion for CI. The southwesterly flows of the monsoonal warm–moist air, enhanced by the UHI effects along the city belt, allow the development of convective cells along the city belt, some of which merge with convective clusters during their downstream propagation, and the ultimate generation of several distinct heavy rainfall centers by local convective clusters over coastal Nantong where atmospheric columns are more moist and potentially unstable under the influences of sea breezes. Sensitivity simulations show small contribution of Nantong’s UHI effects to the heavy rainfall event. The above findings help elucidate how the UHI effects could assist the CI in a weak-gradient environment, and explain why urbanization can contribute to increased downwind mean and extreme precipitation under the influences of favorable regional forcing conditions. Significance Statement The urban heat island (UHI) effects tend to produce more rainfall on its downwind side than that on the other sides, but alone could hardly account for the generation of heavy rainfall. This study examines the influences of the UHI effects associated with a city belt over the Yangtze River Delta on generating an afternoon heavy rainfall event over coastal Nantong that is 70–100 km downwind from the city belt. Results show (i) the downwind advection of the UHI effects; (ii) the initiation of convective storms along the city belt, and their subsequent downstream propagation, leading to the generation of heavy rainfall over Nantong; and (iii) an important role of sea breezes in generating the heavy rainfall event.