Compact Urban Form Research Articles

Urban functional area building carbon emission reduction driven by three-dimensional compact urban forms’ optimization

Previous optimization approaches with regard to the overall urban form can no longer meet the demand for accurately implementing building energy consumption carbon emission reduction at small spatial scales. This study constructed building energy consumption-oriented urban functional area division method using points of point-of-interest (POI), three-dimensional building and roadway data with urban functional areas as units. The method linked POI to buildings, using building volume as an auxiliary parameter to determine the functional attributes of blocks while taking into account the building operational energy consumption. The residential functional areas, commercial functional areas and industrial functional areas, which account for more than 90% of the total building operation energy consumption and the top three in terms of share, are selected as the analysis objects. Geographic detector was applied to analyze the mechanism of carbon metabolism in the compact spatial patterns of these three functional areas. The case study in Xiamen, China reveals that (1) Three-dimensional building compactness is an important factor influencing building energy consumption(normalized difference vegetation index q-value is 0.227); (2) the difference in energy consumption between different compactness classes in residential and commercial functional areas is significant, while not in industrial functional areas; (3) according to the three-dimensional building compactness optimization path of this study, the building operation energy consumption in central Xiamen City could be optimized to reduce by 7% in 2015. Based on the self-created building energy consumption-oriented functional area division method, it is concluded at the functional areas scale that different types of urban functional zones have different optimization methods for three-dimensional building compactness. Such optimization can save construction resources and achieve double carbon more effectively.

Legal Perspectives on New Urban Quarters in Germany: Living the Dream of the Compact City?

The ‘leitmotif’ of the compact city has become a widely embraced template for sustainable urban development. Particularly infill and redevelopment areas, as well as many planned new settlements, have been built following the planning principles of urban compaction. Numerous positive effects are attributed to high-density settlements such as more efficient use of infrastructure and less reliance on automobile travel. Planning law and policies, in Germany as well as other countries around the world, regularly strive to advance high-density developments, but it is by no means clear whether the prescribed densities in planning policies actually lead to vibrant and healthy places which fulfill the expectations of their inhabitants with regards to their quality of life. The study aims to analyze the relation between binding land-use plans in Germany and individual perceptions of urban density through a case study-based survey. This paper contributes to providing new information on achieving compact urban form and quality of life in new urban quarters by analyzing the change of densities over the past three decades in ‘large’ urban developments across Germany, by an in-depth assessment of planned and built densities within an archetypal urban extension and finally by contrasting these ‘objective’ figures and findings with the ‘subjective’ feelings of inhabitants. For sources of information, this paper draws from literature, surveys and empirical analyses as well as desktop-studies.

The Governance of Traffic Noise Impacting Pedestrian Amenities in Melbourne Australia: A Critical Policy Review.

By identifying a unified aim of Federal, State, and Local government authorities to deliver healthier, more liveable urban spaces and enable walkable neighbourhoods in Melbourne, Australia, questions emerge regarding noise data collection methods and the policies that aim to protect pedestrian areas from potential increases in urban traffic noise. It highlights a missed opportunity to develop strategies that provide explicit guidance for designing more compact urban forms without diminishing pedestrian amenities. This study investigates the governance of traffic-induced noise pollution and its impact on pedestrian amenities in Melbourne, Australia. It aims to identify the government bodies best positioned to protect pedestrians from noise pollution and evaluate the strategic justification for reducing traffic noise to enhance urban walkability. This research employs a semi-systematic policy selection method and a hybrid critique and review method to evaluate the multidisciplinary governance frameworks engaged in the management and mitigation of traffic noise in Melbourne. Key findings reveal that while traffic noise poses significant health risks, current policies overlook its impact on pedestrian amenities in urban areas. This study emphasises the benefits of qualitative and subjective noise data collection to inform policy-makers of the pedestrian aural experience and impacts. Discussion points include noise management strategies and the value of implementing metropolitan-scale noise-mapping to illustrate the impact of noise rather than quantities of sound. The conclusions demonstrate that there is strategic justification for managing traffic-induced noise pollution to protect pedestrian areas within international, federal, and state government policies and implicit rationale at a local level.

Relational geographies of urban unsustainability: The entanglement of California’s housing crisis with WUI growth and climate change

One of California’s most pressing social and environmental challenges is the rapid expansion of the wildlands–urban interface (WUI). Multiple issues associated with WUI growth compared to more dense and compact urban form are of concern—including greatly increased fire risk, greenhouse gas emissions, and fragmentation of habitat. However, little is understood about the factors driving this growth in the first place and, specifically, its relationship to urban–regional housing dynamics. This paper connects work in urban social science, urban and regional planning, and natural sciences to highlight the potential role of housing crises in driving displacement from the urban core to relatively more affordable exurbs, and with this, WUI growth. We analyze this relationship in California, which leads the nation in lack of affordable housing, scale of WUI growth, and many associated WUI hazards, including wildfire. We offer three related arguments: first, that California’s affordable housing crisis, with its effect of driving migration to exurban areas, should be recognized as a significant urban form-related sustainability challenge; second, that to understand this challenge scholars must expand the spatial scale and analytic toolkit of both urban and WUI analysis through relational, mixed methods research; and third, that political and programmatic efforts to address California’s housing crisis should undergird efforts to address WUI growth and climate change. Ultimately, we argue that expanding access to affordable urban housing can produce a more sustainable and just urban form that mitigates WUI-related climate and environmental impacts and reduces the vulnerability of growing numbers of WUI residents living in harm’s way.

Analysis of Urban Form Dynamics in The Suburbs of Surakarta City 2013-2023

Urban Form has become necessary for city planning management to see the sustainability of a city. A better understanding of different urban forms is imperative to facilitate the evolution of cities towards a more sustainable urban development trajectory in the future. The study aims to analyze the dynamics of urban form and the changes in land cover within the peri-urban area of Surakarta City, which is directly influenced by the development of Surakarta City. The analysis was conducted from a landscape ecology perspective, employing a spatial metrics approach at the landscape level to assess the dynamics of urban form using quantitative descriptive, including a spatial approach. A similar approach was adopted at the class level in order to examine the dynamics of land cover changes. The results of the image analysis were validated using the Kappa index, yielding an image accuracy level of 0.86 (86%). The results of this study show that the urban form in the peri-urban area of Surakarta City tends to move towards a compact urban form. Meanwhile, each land cover, vegetation, and water body become increasingly fragmented, with areas becoming narrower as time passes. Built-up and agricultural land are becoming more compact and concentrated along with development. In conclusion, the dynamics of urban form in the peri-urban area of Surakarta City tends to lead to compact urban form.

Exploring the nexus between water quality and land use/land cover change in an urban watershed in Uruguay: a machine learning approach.

The expansion of urban areas contributes to the growth of impervious surfaces, leading to increased pollution and altering the configuration, composition, and context of land covers. This study employed machine learning methods (partial least square regressor and the Shapley Additive exPlanations) to explore the intricate relationships between urban expansion, land cover changes, and water quality in a watershed with a park and lake. To address this, we first evaluated the spatio-temporal variation of some physicochemical and microbiological water quality variables, generated yearly land cover maps of the basin adopting several machine learning classifiers, and computed the most suitable landscape metrics that better represent the land cover. The main results highlighted the importance of spatial arrangement and the size of the contributing watershed on water quality. Compact urban forms appeared to mitigate the impact on pollutants. This research provides valuable insights into the intricate relationship between landscape characteristics and water quality dynamics, informing targeted watershed management strategies aimed at mitigating pollution and ensuring the health and resilience of aquatic ecosystems.

Urban spatial structure and air quality in the United States: Evidence from a longitudinal approach

Previous studies on the relationship between urban form and air quality: (1) report mixed results among specific aspects of urban spatial structure (e.g., urban expansion, form, or shape) and (2) use primarily cross-sectional approaches with a single year of data. This study takes advantage of a multi-decade, longitudinal approach to investigate the impact of urban spatial structure on population-weighted concentrations of PM2.5 and NO2. Based on fixed-effect regression models for 481 urban areas in the United States spanning from 1990 to 2015, we found significant associations between various aspects of urban spatial structure and air quality after controlling for meteorological and socio-economic factors. Our results show that population density, compact urban form, circularity, and green space are associated with lower concentrations. Conversely, higher rates of urban expansion, industrial area, and polycentricity are associated with higher concentrations. For large cities (total population: 180,262,404), we found that increasing key factors from each urban spatial structure category (i.e., greenness, population density, compactness, circularity) by a modest 10% results in 10,387 (12,376) fewer deaths for PM2.5 (NO2). We recommend that policymakers adopt comprehensive strategies to increase population density, compactness, and green spaces while slowing urban expansion to reduce the health burden of air quality in US cities.

Reducing residential cooling demand in a sprawling desert city through vertical urban densification

Traditional desert cities used a compact urban form since it provides benefits in terms of thermal comfort both in urban and interior spaces. However, many current desert cities have shifted to a sprawling model with isolated low-rise buildings, leading to longer travel distances, increased land use, inadequate public space, and higher demand for building cooling. Our study aims to investigate how vertical urban densification can reduce residential cooling demand in hot-dry regions. To achieve this, we compared single-family houses with high-rise multi-family houses in Hermosillo, Mexico. Eight case studies of real houses were selected, representing the city's building stock, including one- and two-story single-family houses, and high-rise multi-family houses. We use dynamic energy simulations to assess the effectiveness of changing building's shape against improving its insulation. Our results indicate that increasing vertical density leads to a reduction in the envelope-to-volume ratio, resulting in a significant decrease in cooling demand. Moving from a one-story single-family house to a high-rise multi-family house can lead to a 72 % reduction in annual cooling demand. Matching the façade material properties of single-family houses and multi-family houses reduces the cooling demands of the single-family houses by 16 %–31 %. However, they still have higher cooling demands compared to high-rise multi-family houses, suggesting that building form has a greater impact on cooling than thermal insulation. Our findings highlight the substantial energy savings achievable by transitioning from detached single-family houses to high-rise multi-family developments in desert cities.

Impact of urban compactness on carbon emission in Chinese cities: From moderating effects of industrial diversity and job-housing imbalances

In the context of sustainable urban space utilization and carbon neutrality, this study systematically explores the relationship between urban form and carbon emissions in China from 2005 to 2020. Utilized night-light and Open-source Data Inventory for Anthropogenic CO2 data from 260 cities to measure urban form and carbon emissions, the threshold effect of urban form on carbon emissions was identified, and the moderating effects of industrial diversity and job-housing imbalances were explored. The results of the study show that, firstly, as urban form becomes compact, carbon emissions within built-up areas and cities both show a trend of decreasing and then increasing. In small and medium-sized cities, urban compactness tends to reduce carbon emissions, while in large and mega-cities, a more compact urban form increases carbon emissions. In addition, in cities with high industrial diversity and low job-housing imbalances, a more compact urban form helps to reduce carbon emissions. To optimize the carbon reduction benefits of urban compactness, our study offers urban planners’ insights for comprehensive planning that integrates urban form with both production and residential considerations.

Compact city and urban planning: Correlation between density and local amenities

Many scholars and planners emphasise the role of compact cities in sustainable urban development. Compact urban form is seen as a way to encourage people, for example, to drive less and walk more, which reduces transport-related GHG emissions. This argument, however, is strongly dependent on local amenity development that can support such local living. In plan-making, a common practice is to try to ensure the realisation of services with a high Gross Floor Area (GFA) residential infill development to raise the local population density. In this paper we are seeking quantitative insight on the resolution under which urban density, as measured by GFA volume, correlates with the growth of urban amenities and liveability. Specifically, we are seeking the direction in which correlation changes when moving from a larger geographical scale (low resolution) towards a smaller scale (high resolution) of walkable reach. Our study shows a clear correlation between urban amenities and planned GFA at low-resolution scales, but that correlation decreases at higher-resolution scales (walkable neighbourhood level), indicating that urban amenities tend to cluster in different locations than density is planned. Based on these findings, we argue that, if the aim of urban planning is to foster the growth of local amenities, it should shift its focus towards larger patterns of urban development rather than emphasising GFA in detailed plan-making.

The Ideology of Sustainable Cities

This article focuses on the concept, characteristics, theoretical research, and international mainstream urban models of sustainable cities. Sustainability city refers to a city that is able to provide sustainable well-being for its inhabitants without reducing urban ecosystem services under certain socio-economic conditions. The theoretical study of sustainable cities has a wide range of perspectives covering all aspects of social development. It deals primarily with the physical composition of cities and the more abstract environmental, economic, social, cultural, political systems, and social equity aspects, and is characterised by efficient public transport systems, the use of renewable energy sources, sustainable buildings, and an overall commitment to reducing carbon emissions. Factors involved in sustainable urban forms such as new urban spatial forms, urban-rural relationships, scale and density, transport principles and land use patterns are explored. The validity of the compact city theory is proved or disproved from different perspectives, and the negative impacts of compact urban form, including the impact of high-density buildings on the ecosystem services of urban green spaces and urban biodiversity. In the context of rapid urban change and globalisation, the construction of sustainable cities is bound to face more challenges and opportunities. These studies have greatly enriched the connotation of sustainable cities and laid a theoretical foundation for the practice of building sustainable cities.

Suburban Futures, Density and Amenity: Soft Densification and Incremental Planning for Regeneration

This article explores practical aspects of the compact city agenda as it applies to the ongoing densification of car-dependent suburbs, focusing on Melbourne, Australia. While the idea of compact cities has widespread policy support globally, debate continues regarding the negotiation of compact urban form and its implications for issues like overcrowding, tree canopy, waterways, urban heat, and so forth. Irrespective of the debate, Australian cities are experiencing rapid urban infill, with all areas becoming denser. Some areas of strategic attention afford master planning and planning forethought; however, most of the land in these cities, and at least half of the dwellings being redeveloped, has suburban form, with little or no strategic planning consideration, despite doubling and, in some cases, tripling population density into the future. Significantly, many areas are or will soon achieve population densities that can support vibrant commercial centers, but with little capacity or interest in top-down planning for adding necessary amenities and services. This article shows how, with minimal effort, planning authorities could subtly alter land use planning to allow incremental, but planned, growth of commercial areas, create the destinations the suburbs need to make them vibrant, and deliver less car-dependent local centers.

Morphology changes and the expansion of major port cities in the Philippines from 1990 to 2020

Research concerning urban expansion has been conducted worldwide in the context of global urbanization, yet comprehensive and systematic research on urban growth and morphological changes in Asia is lacking. In this study, the land use, population, and economic development of nine major port cities in the Philippines from 1990 to 2020 were analyzed. The urban land density inverse S function was used to conduct an in-depth analysis of changes in urban spatial morphology. The urban growth patterns were studied by landscape expansion indexes were studied. The results showed that the land area of nine port cities increased by 246.7 km2. Infill expansion in Metro Manila, Cebu, and Bacolod accounted for >60 % of the newly added urban land and has led to a more compact urban form; edge and outlying expansion in General Santos, Batangas, Cagayan de Oro, and Iloilo accounted for >80 % and has led to dynamic changes involving compactness and dispersion. Urban boundaries and terrain limit the development of slow and medium-speed expansion cities; the combination with surrounding cities into megacities can be considered in the future. In contrast, rapidly expanding cities need to improve their compactness and efficiency of urban land use.

Impact of urban form on housing affordability stress in Chinese cities: Does public service efficiency matter?

Residential housing affordability stress is an important catalyst of class solidification and the growing worldwide social divide. Based on a quantitative spatial model that considers government utility and decision-making and uses nighttime lighting data, this study utilizes potential urban footprint as an instrumental variable to examine the mechanisms underlying the effects of the urban form on housing affordability stress and the moderating effect of government public service expenditure efficiency. The theoretical model and empirical results indicate the following. (i) The compact urban form increases housing affordability stress through productivity and urban living amenities. (ii) The efficiency of government public service expenditures affects industrial agglomeration externalities and public service accessibility, precipitating a negative moderating effect on the relationship between urban form and housing affordability stress. (iii) Based on LandScan data, a polycentric layout was found to weaken the compact urban form's ability to reduce housing affordability stress and reduce the government spending efficiency's negative moderating effect on public services. These findings demonstrate that the positive externalities of agglomeration production and the rationalization of government public service expenditures play important roles in housing market stabilization, which is helpful in facilitating better resource factor allocations by the government in the urban sprawl process.

Heat vulnerability digital mapping at neighbourhood level in the compact city

This paper analyses the impact of urban form and vegetation on one of the most significant parameters that affect people’s thermal comfort and an indicator of urban heat vulnerability: the mean radiant temperature (MRT). To obtain spatialized results and understand in detail the current thermal situation of different public spaces that are part of the city, we combined the SOLWEIG calculation model included in the UMEP tool for QGIS with Urban Weather Generator for Rhino. Six neighbourhoods of Rome (IT) and the associated areas with typical compact urban forms, ranging from historical centre to modern suburbs, have been analysed in the warmest week of the year (August 03-09) during the most critical hours of the day (10 a.m. - 4 p.m.). Georeferenced maps with the mean values of MRT for the studied period allow us to analyse the thermal behaviour of each public square and neighbourhood and locate possible urban havens during heatwaves. This study is part of a larger work that seeks to define a more accurate approach to quantify heat vulnerability within the urban vulnerability indexes, in light of the climate crisis facing cities.

Influence of the Built Environment on Pedestrians’ Route Choice in Leisure Walking

Exploring the relationship between leisure walking and the built environment will provide an improvement in human health and well-being. It is, therefore, necessary to explore the most relevant scale for leisure walking and how the association between the built environment and leisure walking varies across scales. Three hundred volunteers were recruited to wear GPS loggers, and a total dataset of 268 tracks from 105 individuals was collected. The shortest possible routes between starting and ending points were generated and compared to the actual routes using the paired T-test. An improved grid-based buffer approach was proposed, and statistics for the grid cells intersecting the paths were calculated. Grid cells were calculated for six scales: 50 m, 100 m, 200 m, 500 m, 800 m, and 1600 m. The results showed that the actual paths were on average 24.97% longer than the shortest path. The mean, standard deviation, and minimum and maximum values of the built environment variables were all significantly associated with leisure walking. The most relevant spatial scale was found to be the 100 m scale. Overall, the smaller the scale, the more significant the association. Participants showed a preference for moderately compact urban forms, diverse options for destinations, and greener landscapes in leisure walking route choice.

Incorporating Heat Vulnerability into Local Authority Decision Making: An Open Access Approach

High temperatures and heatwaves are becoming more frequent, but heat vulnerability is rarely considered within local authority city design and statutory land-use planning processes. Here, we describe an approach to assess heat vulnerability in Birmingham, the second largest city in the UK. The approach uses open access data and GIS techniques that are available for built environment practitioners. Heat vulnerability is assessed by combining four datasets: surface temperatures, Local Climate Zones, green space, and Indices of Multiple Deprivation. The assessment shows that central and eastern areas of Birmingham that have the most compact urban form, least green space, and highest levels of deprivation are most vulnerable to heat. We evaluated the approach against previous climate research, examined the approach and datasets at the local scale, and described how heat vulnerability can be (and is being) incorporated into decision making. This project combines three key innovations: (1) the decision-centric process that focuses the method on the decision that needs to be made, minimizing inertia related to scientific or modeling uncertainty and reducing resource-intensity; (2) the co-creation process with Birmingham City Council, who have statutory powers for planning within the city, thereby ensuring that heat vulnerability is embedded within decisions on the suitability, design, and location of sites for future development; and (3) the open access and technically appropriate methodology which can be applied to any urban area in the UK, using the open access datasets described here, or globally, using locally applicable data sources.

The impact of the morphological change of urban spaces in shaping the new microclimate: A case study in Karbala, Iraq

This study intends to investigate the urban morphology in forming microclimatic conditions in urban outdoor spaces. The Research looked at the compact form of a city and analyzed elements linked to air temperature, urban ventilation, and individual thermal comfort at a comprehensive street plan level. The urban design and the availability of open spaces directly impact all of the studied elements. The field study took place in the old city center of Karbala, a typical compact urban fabric, where the relationship between urban morphology and microclimate was explored. The precise street plan and the local buildings patterns were used to determine urban morphology. The software used to perform simulation was the ladybug tool in Grasshopper. The field study results show that the street layout, urban canyon, and open and compact urban form play a significant role in producing microclimatic conditions and influencing bioclimatic parameters as well as Unplanned urban growth may lead to a disregard for crucial elements including solar exposure, wind patterns, and the overall thermal comfort of metropolitan areas. Wide roadways inside conventional urban fabric can also contribute to increased solar radiation exposure. When urban areas are created without sufficient planning, there is a higher possibility of producing spaces that are exposed to excessive sun radiation without suitable shading. resulting in high temperatures and discomfort for pedestrians and other city dwellers.

Sustainable transport modes, travel satisfaction, and emotions: Evidence from car-dependent compact cities

This study investigates how the use of sustainable transport modes relates to travel satisfaction (general evaluation of travel) and travel affect (emotions during travel) in car-dependent compact cities. Thereby, the study provides evidence on sustainable mobility and travel-related well-being in a context of compact urban form but inadequate provisions for public transport, walking, and cycling. A mixed-methods approach was applied comprising quantitative and qualitative analyses of data from the two major cities of Greece, i.e., Athens and Thessaloniki. Travel satisfaction and travel affect are found to be highest for those who walk for commuting, independently of travel time and other factors. Conversely, travel satisfaction and travel affect are lowest for public transport users, largely due to very long travel times but also poor public transport services in one of the two cities. Results indicate that the experience of traveling by public transport, car, and motorcycle within urban areas greatly depends on transport provision and policies. Overall, findings support the idea that to shift to pleasant, satisfying, and sustainable mobility in car-dependent compact cities, car restrictions should be accompanied by massive improvements in public transport, high-quality walking and cycling infrastructure, and an integrated coordination of different modes.

Research on the influencing factors and multi-scale regulatory pathway of ecosystem health: A case study in the Middle Reaches of the Yellow River, China

It has become a hot issue in realizing regional sustainable development to discuss the influencing factors and regulatory pathway of ecosystem health. However, the lack of driving mechanisms and regulatory pathways for ecosystem health limit the development of effective environmental management policies and urban planning. In this study, taking the Middle Reaches of the Yellow River (MRYR) of China as the study area, we introduced spatial weight coefficient and modified coefficient of spatial proximity effect to improve the “Vigor–Organization-Resilience-Ecosystem services” (VORS) model, and adopted the improved VORS model to dynamically assess the ecosystem health level. Then, we provide an in-depth analysis of the mechanisms of climate and human activities affecting ecosystem health. Finally, the multi-scale regulation of ecosystem health was implemented. The results showed that topography, climate, population urbanization, economic urbanization, land urbanization, agricultural activities, environmental pollution, regional policies and other factors all have a significant impact on the ecosystem health, but the direction and extent of impact had obvious spatial heterogeneity. The negative impact of potential evapotranspiration on ecosystem health is significantly higher in urban agglomerations than in other regions. Regular and compact urban forms are conducive to the health of urban ecosystems, and appropriate urban size and strict urban development boundaries are conducive to maintaining high level of ecosystem health in riverine cities. The evolution of the spatial relationship between environmental pollution and ecosystem health in the MRYR (ecologically vulnerable areas in the western region and urban agglomerations in mid-east region) verifies the Environmental Kuznets Curve (EKC). The study area was divided into three eco-management zones at regional scale and ten eco-management zones at county scale by using the spatial superposition analysis method. Based on this, the multi-scale regulation strategies of ecosystem health was proposed. This study improved the assessment model of ecosystem health, expanded the theoretical research on driving mechanism and multi-scale regulation pathways of ecosystem health. The research results can provide scientific basis for environmental management and urban planning in ecologically fragile areas.