The sprawl of U.S. cities has attracted criticism from many sources in recent years. Among the greatest of the cited harms of sprawl is the alleged travel time burden that it imposes on its residents. Previous research has tested the relationship between the sprawl of business activity and travel times by examining only its effects on commuting times and has concluded that people do not choosing housing and work locations to minimize commutes. This research takes a more comprehensive approach by analyzing the relationship between household travel times and sprawl by testing the relationship between access to economic centers and daily household travel time. The relatively minor increase in household travel times with decrease in access to economic centers found by the analysis shows that people logically reduce trips to centers when choosing housing locations with less access to centers. The ability of people to make these reductions in travel is clearly increased by the dispersal of activity from the central business district and other centers. Comparison of predicted household travel times with an estimated rent gradient show that the increase in housing prices with improved access to subcenters is far less than would be expected given the predicted household travel times, contradicting the relationship between household travel time and housing prices embodied in central place theory and its limited polycentric extensions. An analysis of joined trips suggests that households with less access to economic centers used joined trips, in which multiple destinations are visited on a single trip from the home, to reduce household travel. All of the results suggest that auto use enables households throughout the metropolitan area to reduce travel time. The car has greater flexibility and speed than other modes, particularly in areas of lower density. The travel time savings and flexibility that are provided by the dispersal of economic activity have allowed people to choosing housing that they prefer at lower prices with little added transportation cost. Given these benefits we should carefully consider the manner and method we choose to reduce any negative externalities of sprawl and auto use. / Ph. D.

Staden som en handelsplats har djupa rötter och handelns form i våra städer förändras löpande, i samtiden kanske framförallt genom e-handelns intåg. Arenan för kommersiell service är i ständig förändring och när våra städer förtätas har vi genom planering chans att påverka förutsättningarna för kommersiell service. Föremålet för denna studie är förhållandet mellan densitet, service och urban form. Sambandet mellan densitet och urban kommersiell ställs mot en integrationsanalys enligt space syntax för att identifiera om olika områdens urbana form påverkar tillgången till urban kommersiell service. Genom fallstudier av Stockholm och Göteborg visar uppsatsen att över- och underrepresentation av urban kommersiell service i förhållande till befolkningsdensiteten framförallt förekommer i de centrala delarna av staden, men underrepresentation oftare i anslutning till större barriärer. Områden med höga integrationsvärden kan i studiens båda fall kopplas till en stor överrepresentation av kommersiell service.

A large proportion of energy demand comes from urban areas, mostly from buildings and transport, the use of which has impacts on climate and air quality through the emissions of greenhouse gases and other pollutants. To effectively mitigate these impacts, a better understanding of the relationship between energy and urban form variables is crucial. The link between energy and urban variables has been demonstrated before and it is recognised in many aspects of the cities, such as human behaviour and transport dynamics. This research goes forward by analysing the correlation and scaling between energy consumption and different land use typologies derived from urban form variables, as well as at other scales. The work is built on readily available datasets for England to guarantee the replicability of the methodology and ensure the reliability of the results. A combined energy use metric integrating buildings and commute transport produces helpful insights into energy consumption patterns and it is obtained at a large geographic scale. The identification of local scale consumption patterns is attractive to policymakers and planners by providing them detailed information to direct local-level policies. On the other hand, the derived land use typologies deliver new knowledge about the spatialisation of the urban system and to establish the link with the energy use. The results reveal that the relationship between energy and urban variables favours the application of compact city to reduce carbon-based energy consumption. This means that better energy efficiency is achieved by areas with higher population density. The analysis also shows that socio-economic variables have higher impact on energy consumption than physical variables. Moreover, differences at city scale and for the land use typologies are identified, demonstrating the importance of focusing the analysis according to the goal. In sum, the results from this work provide new insights about the relationship between energy and urban characteristics that can be used by policymakers and planners to outline more focused and detailed actions to mitigate energy use in England.

Conventional transportation demand management approaches have had limited success in reducing automobile dependency. As a result, it has become increasingly important to understand the decision-making processes involved in determining travel behaviour. The purpose of this dissertation is to extend research on urban form and travel behaviour beyond adult travel by examining teen travelers aged 13-19 in the Greater Toronto Area. Data from the Transportation Tomorrow Survey (TTS) survey are used to study four main research questions: 1) How has teen mode choice changed from 1986 to 2006? 2) How do these choices vary as teens transition from the 13-15 age group to being of driving age (16-19)? 3) How do these choices vary across the different urban and suburban regions of the GTA? 4) What are some of the differences between teen travel and adult travel? The issue is further probed through the collection of quantitative and qualitative travel data from first year students at the University of Toronto, and a series of focus groups held in locations in the GTA. The first year survey explores attitudes towards different modes in relation to the locational attributes of the respondent‘s hometown neighbourhood. The focus group sessions involve interviews with 26 teen and a take-home parental questionnaire. Results show that across the GTA, active transportation has decreased while auto passenger mode shares have increased. Younger teens walk more and older teens take transit more for both school and discretionary travel. Jurisdictions with better transit supply and orientation have higher transit mode shares for school trips, but discretionary trips have low transit mode shares. Walk mode shares for both school and discretionary travel are similar across all jurisdictions, regardless of whether they are urban or suburban. Additionally, the survey participants' narratives illustrate that the desire to travel actively and independently is strong. However, the reality of the final travel choice is determined by the presence of supportive infrastructure that facilitates active mode choices while shaping perceptions and attitudes formed as a result of daily travel experiences. Findings illustrate the relevance of qualitative work in advancing transportation research--particularly in understanding human travel decisions.

Conventional transportation demand management approaches have had limited success in reducing automobile dependency. As a result, it has become increasingly important to understand the decision-making processes involved in determining travel behaviour. The purpose of this dissertation is to extend research on urban form and travel behaviour beyond adult travel by examining teen travelers aged 13-19 in the Greater Toronto Area. Data from the Transportation Tomorrow Survey (TTS) survey are used to study four main research questions: 1) How has teen mode choice changed from 1986 to 2006? 2) How do these choices vary as teens transition from the 13-15 age group to being of driving age (16-19)? 3) How do these choices vary across the different urban and suburban regions of the GTA? 4) What are some of the differences between teen travel and adult travel? The issue is further probed through the collection of quantitative and qualitative travel data from first year students at the University of Toronto, and a series of focus groups held in locations in the GTA. The first year survey explores attitudes towards different modes in relation to the locational attributes of the respondent‘s hometown neighbourhood. The focus group sessions involve interviews with 26 teen and a take-home parental questionnaire. Results show that across the GTA, active transportation has decreased while auto passenger mode shares have increased. Younger teens walk more and older teens take transit more for both school and discretionary travel. Jurisdictions with better transit supply and orientation have higher transit mode shares for school trips, but discretionary trips have low transit mode shares. Walk mode shares for both school and discretionary travel are similar across all jurisdictions, regardless of whether they are urban or suburban. Additionally, the survey participants' narratives illustrate that the desire to travel actively and independently is strong. However, the reality of the final travel choice is determined by the presence of supportive infrastructure that facilitates active mode choices while shaping perceptions and attitudes formed as a result of daily travel experiences. Findings illustrate the relevance of qualitative work in advancing transportation research--particularly in understanding human travel decisions.

This thesis presents evidence that income polarization is accompanied by increasing social-spatial disparities between areas of the city that were developed in different societal contexts, with different planning approaches, and that have different land use and transportation dynamics. An analysis of the social structure of the Toronto Metropolitan Area finds indications of widespread gentrification in the inner city, socioeconomic decline in the postwar suburbs, and sustained household affluence in the ever expanding outermost suburbs of the metropolitan area. It is argued that, as a political and social endeavor that is embedded in broader development regimes, urban planning influences social-spatial polarization to the extent that it influences urban form.

The urban heat island effect is considered one of the main causes of global warming and is contributing to increasing temperatures in the urban United States. This phenomenon enhances the intensity of summer heat waves and the risk to public health due to increased exposure to extreme thermal conditions. Characteristics of spatial development patterns can significantly affect urban temperature because they are related to the arrangement of development and land surface materials, which are crucial elements needed to determine land surface temperature. While previous studies revealed that the effect of the urban heat island varies depending on different land use types and surface characteristics, few have considered the overall development patterns of urban form. I address this under-studied aspect of heat hazards by analyzing the relationship between spatial development pattern and urban heat island effect across a sample of 353 metropolitan regions of the U.S. Specifically, I employ a series of landscape metrics to measure urban development patterns using a national land cover dataset from the U.S. Geological Survey. Linear regression models are used to statistically isolate the effect of different spatial development patterns on increasing the urban heat island effect while controlling for multiple contextual variables including built-environment, environmental, and demographic characteristics. The result of this study showed that the daytime mean surface urban heat island effect (4.04˚F) is higher than that of nighttime (2.41˚F). Ecological context (i.e. Ecoregions) has proved to be a statistically significant modulator that helps to explain the spatial distribution of the urban heat island effect. Regarding the main research question of this study, the results indicate that specific categories of urban development pattern including density, continuity, and clustering are statistically associated with increasing the urban heat island effect. This initial evidence suggests that the overall development patterns are an important issue to consider when mitigating the adverse impacts related to the urban heat island effect. In addition, when contextual heat contributors are held constant, the intensity of the urban heat island effect can differ depending on the configuration of development in urban areas. This study can be used as a starting point for a comprehensive approach to both spatial land development and hazard-resistant planning by providing alternative ways of measuring and modeling spatial development patterns.

This thesis presents evidence that income polarization is accompanied by increasing social-spatial disparities between areas of the city that were developed in different societal contexts, with different planning approaches, and that have different land use and transportation dynamics. An analysis of the social structure of the Toronto Metropolitan Area finds indications of widespread gentrification in the inner city, socioeconomic decline in the postwar suburbs, and sustained household affluence in the ever expanding outermost suburbs of the metropolitan area. It is argued that, as a political and social endeavor that is embedded in broader development regimes, urban planning influences social-spatial polarization to the extent that it influences urban form.

What are the essential characteristics that constitute historic American neighbor- hoods? Do current regulations promote developments that exhibit these essential characteristics? In this thesis I analyze two historic neighborhoods in an effort to un- cover their architectonic principles. By identifying the key components that comprise these places, we can critically analyze whether regulations, such as Historic Preserva- tion Ordinances and the SmartCode, are adequately designed to govern development practices of residential neighborhoods.

Public transportation policy plays a significant role in facilitating ridership as well as travel modes, economic activities, and environmental aspects. Seoul has experienced rapid urbanization. Also, high density developments and uncontrolled land use gave rise to extensive urban sprawl in the Seoul Metropolitan Areas (SMA). Due to increased use of private vehicles, which created serious traffic congestion, the Seoul Metropolitan Government (SMG) has reformed public transportation policies-introduced bus transportation reform (BTR) in 2004 and reformed fare and ticketing structures in 2009. This research focuses on the relationships between socioeconomic characteristics and commuting patterns by applying smart card data that includes individual travel behaviors during commuting periods. Among regression results, average commuting times are significantly associated with the proportion of population with lower levels of education and the number of public transit stations. These results appear to support the idea that the lower educated people in each district tend to have longer commuting times. Also, the greater availability of public transit stations contributes to shorter commuting times. Finally, analyzing commuting times seems to be important for determining demographic movement as well as locational advantages in certain regions of Seoul based on public transportation policies.