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The American public generally sees its rural communities as autonomous and self-sufficient—inherently resilient. Accordingly, research on federally funded hazard mitigation has disproportionately f...

Populating and depopulating cities have some degree of underutilised land. The duration of vacancy, or length of time a property remains unused, more strongly influences urban decline than the amount of vacant land. Assessment of the duration of vacancy is seldom conducted, due to a lack of linking longitudinal data. This research creates and applies a Python script to track the duration of vacancy in Minneapolis, MN, U.S.A, to create a tool that can be utilised by cities with vacant land inventories. The tool can be used globally to prioritise treatment areas for urban regeneration plans.

In early October 2016, Hurricane Matthew crossed North Carolina as a Category 1 storm, with some areas receiving 0.38–0.46 m (15–18 in.) of rainfall on already saturated soil. The NIST-fund...

This research investigates the Urban Heat Island (UHI) effect in different climate zones in order to analyze the efficacy of UHI mitigation strategies. A base case urban canopy model was developed using statistical urban district information for Houston, Texas. The Urban Weather Generator (UWG) was employed to simulate the UHI effect during the hottest week of the Typical Meteorological Year (TMY3). Two case studies were conducted to represent the impacts of UHIs on the different climate zones. First, a case study was conducted to compare the UHI effect in various climate conditions. We controlled the urban morphology to estimate the effects of the climate zones on UHIs, but the UHI intensity outcomes still considerably differed from one another, ranging from 1.25℃ to 4.35℃. Second, UHI mitigation strategies such as roof vegetation, trees, and grass coverage ratio were tested to measure their sensitivity in different climate conditions. The results show that green roofs have a marginal effect on UHI mitigation in high-rise urban morphology, while increases in grass and tree coverage ratios were effective, especially in hot climates. The results also indicate that the strategies employed should consider the climate’s characteristics in order to encourage a more sustainable built environment.

Green Infrastructure (GI) has gained attention as a strategy for minimizing flood damage and enhancing ecological services in developed and developing areas. Previous studies have investigated the positive effects of GI, focusing primarily on how the amount of GI impacts flood mitigation, but not its shape, connectivity, or quantity. Further, these studies have been mostly based on a single time period and not longitudinal. This paper explores GI conditions in high and low flood risk coastal Texan cities over time to identify the longitudinal effects of GI, controlling for a set of socio-economic, climate/biophysical, and development variables. The research examined sixty-eight coastal Texan cities of over 10,000 in population from 2001 to 2016, conducting spatial panel data models developed in 5-year intervals. Multiple landscape indices measuring size, shape, isolation, and connectivity of GI were used to measure its quantity and condition. Results indicate that GI conditions, especially amount and connectivity levels, appear to be improving in low-risk cities while worsening in high-risk cities. For control variables, a reduction in imperviousness was found to be more effective in managing GI quantity and landscape conditions in low-risk cities than in high-risk cities. These results suggest that planners should enhance efforts to improve current GI conditions, specifically in high flood risk cities. Additionally, conservation policies and transfer of development rights should be examined together with imperviousness regulations to increase current GI conditions.

Housing vacancies have become a major issue in depopulating, or shrinking, cities. All urban areas, however, are subject to some degree of vacant housing. A small percentage is necessary to allow mobility and sufficient space for growth, and is an indicator of healthy urbanization. Conversely, widespread housing vacancies may indicate structural crisis due to property abandonment. Land area and population changes, shifts in employment, demographic trends, development intensity, and economic conditions are primary drivers of housing vacancies. The degree to which these interrelated factors contribute can fluctuate by city. This paper explores relationships between factors contributing to housing vacancies over time to identify changes in underlying factors. The research examines U.S. cities of over 100,000 population over the period of 1960–2010, conducting multivariate regression analyses in 10-year periods and performing longitudinal panel analyses. The regressions examine changes in urban housing vacancy factors over time while the panel models assess which factors have remained consistent. The panel model results indicate that population change, percent nonwhite populations, unemployment and density are consistent, significant predictors of housing vacancies, The incremental regression models suggest that unemployment and regional location have also been strong indicators of housing vacancies. These results, while somewhat exploratory, provide insight into long-term data that cities should track over time to determine the optimal policy approaches to offset housing vacancies.

Neighborhood decline is a critical issue in shrinking cities. Components of sustainable urbanism such as mixed land uses have risen as possible urban planning-based approaches to help mitigate urban and neighborhood decline. This research identifies examines if mixed land uses can help mitigate urban decline by using the tax delinquent status of single family houses as a proxy for decline in Dayton, Ohio, USA. Logistic regression models are utilized to estimate the probability of tax delinquency. The results suggest that the proximity to mixed land uses is associated with increasing or decreasing the probability of tax delinquent for single family lots. The number of commercial and industrial lots in a neighborhood also has effects on the probability of a lot becoming tax delinquent, but the specific types of commercial and industrial lots dictate the direction of effects. The existence of commercial apartment lots, retail lots, and industrial food and drink plant lots were shown to help decrease the probability of tax delinquent lots. Also, decreasing the amount of property tax applied to parcels can help to limit distress in neighborhoods. This research contributes to the ongoing efforts to stymie the amount of residential abandonment in depopulating and declining cities.

The effects of urban expansion and population change on vacant land patterns are not fully understood. While the majority of previous research documents that depopulation can result in increased vacant urban areas, there are conflicting findings in regards to the effects of urban expansion. What remains unclear is whether higher urban elasticity (expansion in size) contributes to increases in urban vacancies, or the inverse. While elastic cities extend their boundaries and develop outwardly, inelastic cities contract or stay the same in size and utilize infill development. This research sought to determine if urban elasticity plays a significant role in contributing to urban vacancy increases through an exploratory, quasi-experimental longitudinal analysis of vacant address data from 40 U.S. cities of over 100,000 persons from 2000 to 2010. We compared the top 20 elastic (boundaries expanded the most) and inelastic (boundaries contracted the most) cities. A fixed effects panel model was developed to observe changes over time and differences in total, residential, and business land uses. Results indicate that aggressive urban expansion can contribute to increased urban vacancies, specifically in reference to residential land uses. This finding clarifies what had heretofore been a murky aspect of the urban studies literature.

Despite global projections of increasingly concentrated urban population growth, many cities still suffer from severe depopulation (or shrinkage), which results in increased vacant land/structural abandonment. As a consequence, shrinking urban areas are now seeking ways to more intelligently inventory and manage declining neighborhoods. Smart Shrinkage, a means of planning for fewer people and less development, has become a popular approach to managing depopulation. This research explores current approaches to managing vacant urban land through case evaluations approach, using findings to inform an applied Smart Shrinkage strategy for repurposing vacant lots. Land use prediction modeling is integrated into the process using Dayton, Ohio, USA, as an application site. A GIS-based development suitability model was used to identify pockets of future nodal development, and the land transformation model (LTM) was used to predict areas of future decline. Typologies of vacant/abandoned lots were then developed based on spatial characteristics of each parcel. The result of the process is a framework for executing Smarter Shrinkage—a community-scaled approach integrating land use prediction modeling into the process for managing vacant lots. Findings suggest that forecasts from the LTM require policy mechanisms to be put into place that will allow land to be transformed for nonresidential uses that are consistent with where demand exists. Smarter Shrinkage approaches should emphasize the implementation of newly proposed development only within nodes of high development potential and should utilize temporary or green infrastructure-based functions in areas predicted to become vacant or with low development potential.

The Leadership in Energy and Environmental Design (LEED) has provided abundant resources and guidelines for a new project to become a sustainable anchor in the neighborhood. Paired with a range of checklist, LEED has strong influence on the standards for a sustainable building, and it also has played an iconic role in energy-efficient architecture. However, it is still unclear as to whether or not an LEED certified building enhances environmental benefits to its surroundings. If an LEED certification promises a baseline for an eco-friendly building, then a group of these structures should ensure significant environmental benefits to the society. This is the main question of this study, and the authors answer this hypothesis by examining the relationship of LEED certificates and their influence on outdoor temperature, especially in terms of urban heat island effect. The goal of this paper is to analyze the influence of the LEED certification on urban temperature as an indicator of sustainable architecture's regional interactions. If an LEED certificate is regarded as a strong contributor to a sustainable built environment, then a group of these certificates should result in greater benefits to society. To this extent, the authors question if there is any possible relationship between a large concentration of LEED certified sites and the temperature of their surroundings. To properly assess the research direction, Global Moran's I analysis, Local Moran's I analysis, and Hot Spot analysis are implemented to find the clustered areas of LEED certified buildings. For examining relationships between clustered area and its temperature, correlation efficients are calculated.

Rapid urbanization has accelerated land use and land cover changes, and generated the urban heat island effect (UHI). Previous studies have reported positive effects of neighborhood landscapes on mitigating urban surface temperatures. However, the influence of neighborhood landscape spatial patterns on enhancing cooling effects has not yet been fully investigated. The main objective of this study was to assess the relationships between neighborhood landscape spatial patterns and land surface temperatures (LST) by using multi-regression models considering spatial autocorrelation issues. To measure the influence of neighborhood landscape spatial patterns on LST, this study analyzed neighborhood environments of 15,862 single-family houses in Austin, Texas, USA. Using aerial photos, geographic information systems (GIS), and remote sensing, FRAGSTATS was employed to calculate values of several landscape indices used to measure neighborhood landscape spatial patterns. After controlling for the spatial autocorrelation effect, results showed that larger and better-connected landscape spatial patterns were positively correlated with lower LST values in neighborhoods, while more fragmented and isolated neighborhood landscape patterns were negatively related to the reduction of LST.

The use of energy in the building sector has increased rapidly over the past two decades. Accordingly, various building assessment methods have developed in green building practices. However, the questions still remain in regard to how positively green buildings affect regional surroundings. This study investigates the possible relationship between LEED-certified buildings and urban heat island effect. Using GIS with spatial regression, the study found that constructing an LEED building in a 30-m boundary could possibly lower the temperature of the surrounding environment by 0.35 °C. Also, having a higher certification level, such as Gold or Platinum, increased the lowering effect by 0.48 °C, while a lower certification level, such as Certified or Silver, had a lowering effect of 0.26 °C. Although LEED has gained a substantial amount of interest and skepticism at the same time, the study results could be a potential sign that the Sustainable Sites Credits or energy-efficient materials play a positive role in lowering the temperature.