Urban Form Features Research Articles

A scaling investigation of urban form features in Latin America cities.

This paper examines scaling behaviors of urban landscape and street design metrics with respect to city population in Latin America. We used data from the SALURBAL project, which has compiled and harmonized data on health, social, and built environment for 371 Latin American cities above 100,000 inhabitants. These metrics included total urbanized area, effective mesh size, area in km2 and number of streets. We obtained scaling relations by regressing log(metric) on log (city population). The results show an overall sub-linear scaling behavior of most variables, indicating a relatively lower value of each variable in larger cities. We also explored the potential influence of colonization on the current built environment, by analyzing cities colonized by Portuguese (Brazilian cities) or Spaniards (Other cities in Latin America) separately. We found that the scaling behaviors are similar for both sets of cities.

Examining temporally varying nonlinear effects of urban form on urban heat island using explainable machine learning: A case of Seoul

Many empirical studies have examined the relationship between urban form and canopy layer urban heat island (CUHI). However, these studies mostly have used small sample sizes and statistical methods that assume CUHI responds linearly to urban form features. Additionally, the differences in the effect of urban form on CUHI at different time instances during the diurnal cycle have not received sufficient attention. To address these issues, this study employs a relatively large sample of 1,058 microclimate sensors in Seoul, Korea, and analyzes CUHI at 9 a.m., 3 p.m., and 9 p.m. on a typical summer day. Gradient boosting decision tree (GBDT) based regression model and linear regression model and their variants with spatial information were constructed and compared for each time instance. Results show that spatially explicit GBDT models had the highest accuracy. Feature importance analysis shows that built form factors such as mean building height were more important during the afternoon, while surface fractions such as road surface fraction had greater influences during the morning and nighttime. Partial dependence plots (PDPs) show that urban form features influence CUHI in a complex nonlinear manner that varies for each time instance. PDPs were further scrutinized based on their activation and threshold effects. GBDT model findings directionally aligned with linear regression, but they provided nuanced insights into the form-CUHI relationship. These findings help planners to better understand the complexity of urban climate and intervention required to reduce CUHI magnitude across the diurnal cycle.

Exploring residential built-up form typologies in Delhi: a grid-based clustering approach towards sustainable urbanisation

Previous studies have established a significant link between urban form and sustainability. However, the diversity of micro-scale urban forms in cities in the global south has received limited attention, hindered by the lack of neighbourhood-level spatial data and maps, which poses challenges in exploring micro-urban form features. The study addresses this gap using a grid-based k-means clustering algorithm to identify residential built-up form typologies in Delhi and assess their impact on sustainable urbanisation. The algorithm clusters 100×100 metre grid cells based on their attributes of accessibility, built-up density, and street design. The results show six distinct built-up form typologies in Delhi. However, only 19% of residential areas meet the criteria for sustainable urbanisation, highlighting the need for planning interventions in most areas. The study methodology can be applied to analyse micro-scale urban form features in other cities in the global south, providing a fresh perspective on urbanisation research.

Urban form features determine spatio-temporal variation of ambient temperature: A comparative study of three European cities

Driven by ongoing urbanization and accelerated global warming, urban heat stress develops into a major threat for a large part of the world population. While the literature is clear about the relevance of urban form in modifying urban heat, the spatially explicit context of heat modifications by the built environment is insufficiently explored across cities.Here we develop a consistent methodology based on a machine learning model to determine the predictive features of urban form that shape urban ambient temperature (AT) under different urban and climate conditions. For this, we combine urban climate data at 100 m resolution from the UrbClim model with urban form features computed from different open datasets. We exemplify our innovation by evaluating summer daytime and nighttime temperature variation within three European cities that are representative of distinct geographies and climates: Berlin, Zürich, and Sevilla. Mean AT at dense urban spots was higher by 3 °C (on average) during summer compared to sub-urban sites across all cities. We find that urban form features explain around 2/3 of within-city temperature variations. Vegetation cover and water bodies are most significant in explaining spatial temperature patterns during the daytime, while the impervious land cover is most critical at nighttime. Cooling effect of water areas can accumulate to −1.5 °C, while heating effects of roads can induce +0.5 °C during daytime. The magnitude of effects varies across cities, primarily based on the climate type, altitude, and dominant land-cover. However, further testing should be conducted to develop a better understanding of impact variations. The findings of this research will provide urban planners and policymakers with crucial insights towards heat mitigation and sustainable urban developments through region-tailored modifications and replacement of land-cover.

Exploring the morphogenesis of Ethiopian cities: a comparative analysis of the urban forms of Dire Dawa city with its central and northern Ethiopian counterparts

ABSTRACT This study intends to explore the morphogenesis of Dire Dawa through comparative analysis. Several scholars have claimed that central and northern Ethiopian cities share a common urban form tradition, and this study compares the morphogenesis of Dire Dawa, located on the country’s eastern border, to this morphological thought. The research employs a comparative analysis technique of Dire Dawa’s morphogenesis based on Conzenian urban form elements. The findings reveal that the spatial organization of the case areas of the city deviates significantly from the conventional morphological philosophy of northern and central Ethiopian cities. Thus, the establishment of new ones and the redevelopment and extension of existing urban quarters must consider urban form philosophy in the nation along with the identity and conservation of urban form features. This will enable a well-managed morphological blending that might incorporate significant new concepts with existing local knowledge without having undesirable consequences.

Geospatial analysis framework for evaluating urban design typologies in relation with the 15-minute city standards

Today, the majority of the world’s population lives in cities and it is expected that urban population will continue to grow in the coming decades. The increase in urban population will negatively impact urban performance, measured by equal access to amenities, knowledge creation and economic growth, if cities cannot respond to pressures that arise from increased migration. While urban design principles can help solve these problems, many core concepts of city form are often too abstract to allow for quantification of critical key indicators, comparative benchmarking for best practices and rigorous implementation strategies to ensure success. Given the complexity of how people interact with a city, the critical question arises: How does a city’s shape influence its urban performance? In this paper, we intend to address this fundamental question. First, we propose a framework to create a series of urban form typologies, which describe generally, a city’s shape and size, as a unifying concept to describe a city's design underlying pattern. Second, we propose that the urban form typologies can be quantified through the framework, to establish a disciplined methodology to compare the shape and scale of one city to another. The methodology combines topological (street network) and morphological (building form) features of urban form as well as other metrics related to geographic scale, entropy and density. Third, we provide a unified method to evaluate urban performance in terms of urbanization efficiency, innovation metrics and distribution of amenities. Fourth, we apply this framework to study the relationship between city typology and urban performance in order to determine which city designs are best suited to meet the demands of population growth, resource management, and energy usage. We apply this methodology to data gathered on 24 cities worldwide and their internal 8,228 subdivisions. By grouping the subdivisions into 208 agglomerations based on common urban form features, it is possible to identify and characterize their internal tapestry of city form typologies and evaluate their respective urban performance KPIs. We show that city typologies have a distinct effect on urban performance, quantify this impact and provide comparisons between the different typologies. Finally, we apply this methodology to evaluate the ability for each city typology to achieve the standards set forth by the 15-minute city, a sustainable development proposition of a decentralized city composed of walkable neighborhoods that provide equal access to housing, education and amenities.

Algiers as a Paradigmatic Mediterranean City: El Houma as a Measure of Urban Life

With cities accommodating a growing share of the global population, they are exposed to rapid rates of globalisation and urbanisation that present a significant challenge to their capacity to satisfy people’s needs and aspirations and promote urban life. A thorough understanding of how urban forms can promote or hinder urban life has never been more pertinent. This paper contributes to filling this gap by analysing urban form features and synthesising theoretical and empirical evidence on how the physical design of neighbourhoods promotes or hinders urban life. This paper takes Algiers as a paradigmatic case study to explore the relationship between urban form and urban life in the Mediterranean region. It argues that urban form is a factor in facilitating social activities. The paper will base its investigation on the concept of El Houma, which can provide an effective instrument to measure urban life. El Houma is a term used in Algeria to describe a neighbourhood or an urban area characterised by a strong degree of social sustainability, based on the local socio-cultural life of residents manifested in the social use of urban space. In this respect, the paper will review features of three urban planning movements: medieval urbanism, the 19th-century bourgeois city and modernism. The research will draw on urban morphological analysis and techniques of activity mapping to investigate the relationship between urban forms and urban life, illustrated in El Houma, in three different neighbourhoods that represent the three urban planning strands. The paper concludes that the intensity of El Houma is high in the medieval and 19th-century neighbourhoods due to features of urban forms that foster social use of space, and lower in modernist neighbourhoods due to the lack of appropriate spaces for social interaction and forming social relations between residents. Findings indicate that urban form has a major influence on social use of space, urban life and thus El Houma.

Urban sustainability assessment in Geneva: Relevance of the local neighbourhood unit

The physical characteristics of an urban system are typically heterogeneously expressed, creating distinct neighbourhoods shaped by specific local features. Hence, spatially explicit expression of sustainability across the urban system is expected and should not be ignored. In this paper, we present an empirical study that explicitly accounts for the spatial heterogeneity of local-scale urban form features and the significance of a neighbourhood in the canton of Geneva, Switzerland. Our work first established a typology of urban form features, followed by the definition of local-scale functional neighbourhood boundaries using well-established criteria across the study area. An assessment of the sustainability of the resulting neighbourhoods revealed that significant differences can be observed between the different neighbourhood types across various components of urban sustainability. These results highlight the relevance, and argue for the importance, of incorporating local-scale approaches for more effective urban sustainability assessment to support urban planning and policymaking in the transition towards sustainability.

SMART DATA FOR SMART CITY MORPHOLOGY: THE CASE OF MERIDIA NEIGHBORHOOD IN NICE, FRANCE

Abstract. Nowadays, cities have to withstand multiple challenges such as climate change, increasing urban population, economic cycles, health crises, traffic congestion, rising levels of energy consumption and citizens' expectations. Recently, the smart city has been proposed as a model to face such challenges. Underneath its digital skin, which provides ubiquitous high-tech solutions, the smart city is often presented in continuity with the traditional city, while getting inspired by the modernist or international paradigm (free standing towers, high density development and functional zoning). Is this actually the case? To understand the features of urban form of new smart developments and how these relate to existing approaches in city planning, we propose a quantitative methodology to compare features of multiple city areas, which is based on the computation of a set of 3D morphometrics of the urban environment, and descriptive statistics for each metric. We applied this methodology to compare Nice Meridia, a French example of smart city development, with a traditional neighbourhood, located in the same city. Outcomes show that the smart city neighbourhood shares some morphological aspects with the traditional city, but differs significantly in other respects, showing the interest of quantitative 3D metrics.

Is there social capital in cities? The association of urban form and social capital formation in the metropolitan cities of Indonesia

ABSTRACT High-density urban development is claimed as a suitable urban form in enhancing social capital. However, the relationship between those two variables has not been well empirically explored, leading to the emergence of competing results in the literature. This study aimed to investigate the role of urban physical arrangement or urban form in the social capital formation using Indonesian metropolitan cities as a case study. This research was also the first empirical study to investigate the association between urban form and social capital in Indonesia. The multilevel logistic regression was used to investigate the association between the urban form and several indicators of social capital. The findings revealed that individuals in high residential density areas were less likely to know their neighbours, had lower levels of bridging trust, and less involved in the community’s activities. Meanwhile, street connectivity appeared to have a positive association with bridging trust but negatively related to social networks. Moreover, the land use mix did not seem to be significantly associated with any social capital variables. However, the aggregated data of urban form limited our ability of the present study to provide specific policy recommendations. Nonetheless, this study would still suggest that urban planners and policy makers should be mindful to consider that urban form features might influence the development of social capital. Highlights Multilevel logistic regression confirmed that urban form can be claimed to have association with the formation of social capital in metropolitan cities in Indonesia High density seems to have reverse relationship with the level of knowing neighbour, bridging trust and make residents less involve in community activities. High connectivity contributes in fostering the level of bridging trust but lowering social networks. Meanwhile, land use mix did not appear as significant predictor of social capital

A comparative case study of walking environment in Madrid and Philadelphia using multiple sampling methods and street virtual audits

ABSTRACT The objective of this study is to quantify, using virtual audits in Madrid and Philadelphia, cross-city differences in the walking environment and to test whether differences vary by sampling method. We used two sampling methods; first, a contiguous area combining census units (~15.000 population area for each setting) was selected using the Median Neighborhood Index. Median Neighborhood Index is a summary index that averages Euclidean distances of sociodemographic and urban form features, used to select the median neighborhood for a given city. Second, we selected a population-density stratified sampling of the same number of census units as above. M-SPACES audit tool was deployed, using street virtual audits to measure function, safety, aesthetics, and destinations along each street segment. Madrid streets had lower scores for function (b = −0.29 CI95% −0.55; −0.31) and safety (b = −0.38 CI95% −0.61; -0.14). Madrid had a greater proportion of streets having at least one walking destination in the street segment (PR = 1.92 95% CI 1.55; 2.39). We did not find a significant difference between Madrid and Philadelphia in aesthetics. We found an interaction between safety and sampling methods. This approach can reveal which elements of the built environment account for between-city differences, key to mass influences that operate at the city level.

Exploring the Features of Sustainable Urban Form and the Factors that Provoke Shoppers towards Shopping Malls

This study examined various features of urban form, which promote sustainable development and provoke shoppers toward shopping malls. A field survey was conducted in shopping malls at Hangzhou, which is the capital city of the Zhejiang province, China. Structural equation modeling and a confirmatory factor analysis were used to measure the hypotheses. The results of this study showed that the built environment and entertainment completely mediated the relationship between ambiance and consumption, and they have a positive impact on the environment and shoppers. The built environment and entertainment are viewed as essential elements of physical and social sustainability. Real estate developers, urban planners, and shopping mall managers should consider the design features of urban form to meet sustainable development goals and to attract more shoppers. Testing these relationships via a mediating method is a novel contribution to the study of shopping malls.

Quantifying the Effects of Urban Form on Land Surface Temperature in Subtropical High-Density Urban Areas Using Machine Learning

It is widely acknowledged that urban form significantly affects urban thermal environment, which is a key element to adapt and mitigate extreme high temperature weather in high-density urban areas. However, few studies have discussed the impact of physical urban form features on the land surface temperature (LST) from a perspective of comprehensive urban spatial structures. This study used the ordinary least-squares regression (OLS) and random forest regression (RF) to distinguish the relative contributions of urban form metrics on LST at three observation scales. Results of this study indicate that more than 90% of the LST variations were explained by selected urban form metrics using RF. Effects of the magnitude and direction of urban form metrics on LST varied with the changes of seasons and observation scales. Overall, building morphology and urban ecological infrastructure had dominant effects on LST variations in high-density urban centers. Urban green space and water bodies demonstrated stronger cooling effects, especially in summer. Building density (BD) exhibited significant positive effects on LST, whereas the floor area ratio (FAR) showed a negative influence on LST. The results can be applied to investigate and implement urban thermal environment mitigation planning for city managers and planners.

From walking buffers to active places: An activity-based approach to measure human-scale urban form

Urban form measures have been increasingly used in multidisciplinary research, yet few studies have conceptualized different meanings of human-scale urban form for various population groups. This study proposes an activity-based approach that builds direct links between urban form measures and travel-activity patterns of various population groups. With a case study on older adults' walking activity in Toronto, this study maps potential activity spaces for each population group, and measures the potential of social interaction at a land-parcel level. Based on a population-representative survey data and an open source routing algorithm, this study provides an exploratory method to conceptualize and measure human-scale urban form for different population groups. Further, this method helps to understand the non-linear relationships between conventional urban form measures and travel-activity patterns, and to inform planning interventions on urban form features that are particularly important for a specific population group.

Investigating the relationship between air pollution variation and urban form

Air quality in megacities and its correlation with urban form have become a priority, since numerous cities worldwide are encountering a development bottleneck due to air pollution. This paper analyzed the spatial variations in 8 air pollutants among 18 ambient air monitoring stations across Shanghai based on continuously hourly mass concentration data from 28 days in February 2017. In each of the 18 stations, we created a buffer zone with a radius of 1 km, and derived 18 quantified features of the urban form including points of interest and environmental information by the geographic information system and the Baidu Map program interface. Then, the 18 stations were clustered into 3-level groups by using the k-nearest neighbor method according to every pollutant and urban form. Results showed that the spatial variation differed per pollutant, as did urban form. PM2.5 concentrations were high in the western and low in the eastern of Shanghai, which can be explained by regional influences and the distance from East China Sea. PM10 showed a relatively high level in the developed urban areas, and high buildings with a similar height in these areas significantly restrain the dispersion of PM10. The spatial variations of the 6 gaseous pollutants mainly depend on local human activities and transport-related emissions. The distance to primary road, standard deviation of building floors, and average building floors were the top 3 urban form features influencing the spatial variations of all pollutants. Wind ventilation was identified as a critical index for air quality-oriented urban design.

Do local employment centers modify the association between neighborhood urban form and individual obesity?

Extensive literature examines the relation between land use patterns and obesity, but less work explores whether local employment centers may reduce obesity. Local employment centers may affect obesity via providing agglomeration benefits such as increased job/transportation opportunities and closer proximity to local facilities/destinations. We utilized a large serial cross-sectional health survey from Los Angeles, California, conducted over three periods, to examine whether the presence of local employment centers modifies the association between land use patterns and individual body mass index. We retrieved individual health and sociodemographic data from the Los Angeles County Health Survey (2002, 2005, and 2007). To this Health Survey, we linked land use attributes at the census tract level collected from the Southern California Association of Governments. Our log-transformed regression models present interactions between local employment centers, neighborhood urban form features, and body mass index. Although most findings are consistent with previous studies, some of land use factors hypothesized to reduce the risk of obesity could have counterintuitive associations unless local employment centers were controlled. The unexpected results of our land use coefficients indicate that the tenet of New Urbanism may not necessarily promote health benefits. Our findings suggest that modifying the built environment may be effective in reducing obesity only in areas with high degree of local employment centers. Future studies would benefit from longitudinal and experimental, rather than cross-sectional, study designs that rigorously test the potential causal role of New Urbanism on obesity.

Kaye Bock Student Paper Award

Berkeley Planning Journal, Volume 27, 2014 Kaye Bock Student Paper Award The Kaye Bock Student Paper Award is named in loving memory of Kaye Bock—DCRP’s Student Affairs Officer for over 20 years—to honor her unbounded concern for and commitment to graduate students in this department. It is intended as an expression of gratitude from the Berkeley Planning Journal to Kaye for her critical support during our first two decades of publication. The winner is chosen by the editorial board of each volume of the Journal. It is given to an author who is currently enrolled as a student, and whose paper is an outstanding example of scholarship exemplifying Kaye’s commitment to underrepresented issues or peoples. The Award is accompanied by a $250 cash gift. This year we have selected Geoff Boeing for his article, “ LEED-ND and Livability Revisited.” Boeing uses the Temescal neighborhood in Oakland, CA to show how the LEED-ND criteria for Neighborhood Pattern and Design (NPD) can potentially overlook places rated highly as “livable” that are not captured in the current rating system. His research examines the LEED-ND certification system and questions the ability of the system to adequately address differences in community values. Geoff Boeing is a Ph.D. student studying City and Regional Planning at UC Berkeley. His research revolves around urban form, complexity theory, and the intertwined relationship between normative urban design and emergent features of urban form arising from complex systems. He is also the graduate student instructor for UC Berkeley’s Urban Informatics and Visualization course.

Green cities and health: a question of scale?

BackgroundCities are expanding and accommodating an increasing proportion of the world's population. It is important to identify features of urban form that promote the health of city dwellers. Access to...

GREEN CITIES AND HEALTH: A QUESTION OF SCALE?

Background and Aims: Cities are expanding and accommodating an increasing proportion of the world’s population. It is important to identify features of urban form that promote the health of city dw...

Spatiotemporal Evolution of Urban Form and Land-Use Structure in Hangzhou, China: Evidence from Fractals

Using fractal theory and urban land-use maps for 1949, 1959, 1980, and 1996, this study is devoted to analyzing the evolutionary features of urban form and land-use structure in Hangzhou, China. We find that self-similarity exists in both the built-up area and the municipal area, and fractal properties tend to become better defined with time. The fractal dimension of each type of land use is less than that of all land use. From 1980 to 1996, the fractal dimensions of residential, industrial, and external transport increased while those of educational and virescent land use decreased, indicating that partial degradation accompanied holistic optimization during the process of Hangzhou's self-organizing evolvement. The mechanisms of the spatiotemporal evolution of urban form in Hangzhou are discussed, including socioeconomic development and the dispersal or concentration of activities. The Tandabing approach to urban spatial expansion, the Jianfengchazhen approach to urban construction, and a top-down urban management style led to differences in fractal evolution between Chinese and Western cities.