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Research Theme: Land Use & Planning

From the scales of the building to the region; includes transportation, housing, infrastructure, community, ecology

Legacies of redlining lead to unequal cooling effects of urban tree canopy

Jung, M. C., Yost, M. G., Dannenberg, A. L., Dyson, K., & Alberti, M. (2024). Legacies of redlining lead to unequal cooling effects of urban tree canopy. Landscape and Urban Planning, 246. https://doi.org/10.1016/j.landurbplan.2024.105028
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Abstract

Redlining—a racially discriminatory policy of systematic disinvestment established by the Home Owners’ Loan Corporation (HOLC) in the 1930s and continued until the late 1960s—still influences the contemporary landscape of cities in the US. While the heterogeneous distribution of land surface temperature and tree canopy cover between neighborhoods with different HOLC grades have been recently examined, the development of long-term and city-specific heat management strategies is still limited. Here, we explored the effect of redlining in Portland, Oregon, and Philadelphia, Pennsylvania, to assess its contemporary impact on climate equity. We performed a change analysis of land surface temperature and tree canopy area over the past and introduced mixed-effects models to test the intra- and inter-city differences in canopy cooling effects between the different HOLC grades. We found that (1) persistent temporal patterns of lower land surface temperatures and larger tree canopy areas are observed in higher HOLC grades, (2) greater green equity was achieved through contrasting temporal changes in tree canopy areas across HOLC grades in Portland and Philadelphia, and (3) opposite patterns exist between these cities, with stronger canopy cooling effects in neighborhoods with a Low HOLC grade in Portland and those with a High HOLC grade in Philadelphia. Differences in tree canopy change between the two cities over the past decade highlight potential influences of city-specific tree planting practices. Local planners should back tree planting initiatives to equitably mitigate urban heat exposure, considering historical redlining contexts and contemporary landscape features.

Keywords

Redlining; HOLC grade; Tree canopy; Land surface temperature; Tree equity

UW researchers issue state-level policy recommendations for transit-oriented development

CBE Researchers developed a report “Finding Common Ground: Best Practices for Policies Supporting Transit-Oriented Development,” with the Mobility Innovation Center and led by the Washington Center for Real Estate Research.  Project Team: Mason Virant, Associate Director, Washington Center for Real Estate Research Christian Phillips, Urban Design and Planning PhD Program Steven C. Bourassa, PhD Director, Washington Center for Real Estate Research Arthur Acolin, Associate Professor, Runstad Department of Real Estate Visit the project page here.

Window View Quality: Why It Matters and What We Should Do

Ko, W. H., Schiavon, S., Altomonte, S., Andersen, M., Batool, A., Browning, W., Burrell, G., Chamilothori, K., Chan, Y.-C., Chinazzo, G., Christoffersen, J., Clanton, N., Connock, C., Dogan, T., Faircloth, B., Fernandes, L., Heschong, L., Houser, K. W., Inanici, M., … Kent, M. (2022). Window View Quality: Why It Matters and What We Should Do. Leukos, 18(3), 259–267. https://doi.org/10.1080/15502724.2022.2055428

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Hoseok Sa

Research Interests: Regional econ. development (tech innovation, human capital, regional industry), Transportation planning/policy (travel behavior, mobility, sustainable transportation), intersection between planning (or transportation), population/public health, and climate change, and urban form

Higher Depression Risks in Medium- Than in High-Density Urban Form Across Denmark

Chen, T.-H. K., Horsdal, H. T., Samuelsson, K., Closter, A. M., Davies, M., Barthel, S., Pedersen, C. B., Prishchepov, A. V., & Sabel, C. E. (2023). Higher depression risks in medium- than in high-density urban form across Denmark. Science Advances, 9(21), eadf3760–eadf3760. https://doi.org/10.1126/sciadv.adf3760

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Abstract

Urban areas are associated with higher depression risks than rural areas. However, less is known about how different types of urban environments relate to depression risk. Here, we use satellite imagery and machine learning to quantify three-dimensional (3D) urban form (i.e., building density and height) over time. Combining satellite-derived urban form data and individual-level residential addresses, health, and socioeconomic registers, we conduct a case-control study (n = 75,650 cases and 756,500 controls) to examine the association between 3D urban form and depression in the Danish population. We find that living in dense inner-city areas did not carry the highest depression risks. Rather, after adjusting for socioeconomic factors, the highest risk was among sprawling suburbs, and the lowest was among multistory buildings with open space in the vicinity. The finding suggests that spatial land-use planning should prioritize securing access to open space in densely built areas to mitigate depression risks.

Scaling Down from the Neighborhood in Urban Planning Research and Practice: The Potential Benefits of a Micro-Scale Focus

Walter, R. J., Tillyer, M. S., Ramiller, A., & Acolin, A. (2023). Scaling Down from the Neighborhood in Urban Planning Research and Practice: The Potential Benefits of a Micro-Scale Focus. Journal of Planning Education and Research. https://doi.org/10.1177/0739456X231175593

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Abstract

The neighborhood has been the dominant spatial unit in urban planning since the early 20th century. Criticisms of the neighborhood unit include disagreements about defining boundaries, methodological challenges in capturing neighborhood effects, and negative impacts on communities. With advancements in data management, and public data available at smaller units (street block or property), quantitative analyses are possible at the micro-scale. This commentary draws on crime research and prevention to illustrate the benefits of micro-scale approaches to quantitative analyses in the field of urban planning, arguing that the devolution to smaller scales may be a vehicle for efficient resource allocation.

Utilizing Fractal Dimensions as Indicators to Detect Elements of Visual Attraction: A Case Study of the Greenway along Lake Taihu, China

Fan, R., Yocom, K. P., & Guo, Y. (2023). Utilizing Fractal Dimensions as Indicators to Detect Elements of Visual Attraction: A Case Study of the Greenway along Lake Taihu, China. Land (Basel), 12(4), 883–. https://doi.org/10.3390/land12040883

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Abstract

It is widely acknowledged that the quality of greenway landscape resources enhances the visual appeal of people. While most studies have evaluated visual perception and preference, few have considered the relationship between the distribution of greenways in relation to the proximity of water bodies such as lakes and rivers. Such an investigation requires an in-depth analysis of how to plan and design greenways in order to better enhance people's willingness to access and utilize them. In this research we propose specific color brightness and contour visual attraction elements to further discuss the quality of greenway landscape resources in the rapidly urbanizing Lake Taihu region of China. Specifically, we utilize a common method in fractal theory analysis called counting box dimension to calculate and analyze the sample images. The method generates data on fractal dimension (FD) values of two elements; the optimal fractal dimension threshold range; the characteristics exhibited by the maximum and minimum fractal dimension values in the greenway landscape; and the relationship between the two visual attraction elements allowing us to derive distribution of the greenway and water bodies. The results reveal that greenway segments with high values of the visual attraction element of color brightness fractal dimension (FD) are significantly closer to the lake than those subject to high values of the visual attraction element. Some segments are even close to the lake surface, which is because the glare from the direct sunlight and the reflection from the lake surface superimposed on each other, so that the greenway near the lake surface is also affected by the brightness and shows the result of high color brightness values. However, the greenway segments with high values of contour element FD are clearly more influenced by plants and other landscape elements. This is due to the rich self-similarity of the plants themselves. Most of the greenway segments dominated by contour elements are distant from the lake surface. Both color brightness and contour elements are important indicators of the quality of the visual resources of the Lake Taihu Greenway landscape. This reveals that the determination of the sub-dimensional values of color brightness (1.7608, 1.9337) and contour (1.7230, 1.9006) visual attraction elements and the optimal threshold range (1.7608, 1.9006) can provide theoretical implications for the landscape planning and design of lake-ring type greenways and practical implications for assessing the quality of visual resources in greenway landscapes.

Keywords

color brightness; contour; visual attraction; fractal dimension (FD); boxplot; Lake Taihu

Does Compact Development Mitigate Urban Thermal Environments? Influences of Smart Growth Principles on Land Surface Temperatures in Los Angeles and Portland

Won, Jongho, and Meen Chel Jung. 2023. Does Compact Development Mitigate Urban Thermal Environments? Influences of Smart Growth Principles on Land Surface Temperatures in Los Angeles and Portland. Sustainable Cities and Society 90.

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Abstract

The smart growth paradigm has emerged as a major planning framework to respond to the adverse outcomes of reckless development, but its influences on urban thermal environments are underexplored in the scholarly literature. Since elevated land surface temperature (LST) is closely related to the physical expansion of developed areas, it is necessary to identify the effects of smart growth strategies on LST. This study, therefore, investigated the relationships between LST, landscape variables, and smart growth variables at the census block group level in two distinct urban locales: the City of Los Angeles, California, and the City of Portland, Oregon, from 2010 to 2018. Through multivariate analyses—including the principal component analysis (PCA), K-means clustering, analysis of covariance (ANCOVA), and regression models—this study revealed the potential of urban forms promoted by the smart growth principles comprehensively to mitigate LST. Given the different features of built environments and planning systems between the two cities, the results of this study also indicate the necessity of considering local contexts rather than suggesting a “one-size-fits-all” policy.

Keywords

Smart growth; Compact development; Land surface temperature; Urban form; Landscape

Coastal Adaptations with the Shoalwater Bay Tribe: Centering Place and Community to Address Climate Change and Social Justice

The proposed community-based participatory action research project is a collaborative research, planning and design initiative that will enable a UW research team to work with the Shoalwater Bay Indian Tribe to explore sustainable and culturally relevant strategies for an upland expansion in response to climate change-driven sea level rise and other threats to their coastal ecosystems and community. The situation is urgent as the reservation is located in the most rapidly eroding stretch of Pacific coastline in the US, on near-sea-level land vulnerable also to catastrophic tsunamis. The project will advance the Tribe’s master plan and collaboratively develop a model of climate adaptive, culture-affirming and change-mitigating environmental strategies for creating new infrastructure, housing and open spaces in newly acquired higher elevation land adjacent to the reservation. Design and planning strategies will draw on culturally-based place meanings and attachments to support a sense of continuity, ease the transition, and create new possibilities for re-grounding. Sustainable strategies generated by the project will draw on both traditional ecological knowledge and scientific modeling of environmental change. The project will involve the following methods and activities:

  • The creation of a Tribal scientific and policy Advisory Board with representatives from the Tribal Council, elder, youth, state and county agencies, and indigenous architects and planners;
  • Student-led collaborative team-building and research activities that will also engage Tribal youth;
  • Systematic review of the Tribe’s and neighboring county plans;
  • Interviews, focus groups and community workshops to identify priority actions, needs and strategies;
  • Adaptation of existing research on sustainable master planning, design and carbon storing construction materials; and
  • The development of culturally meaningful and sustainable building prototypes.

Deliverables include a report of findings summarizing community assets and values, and priorities for the upland expansion vetted by Tribal leaders, documentation and evaluation of the UW-community partnership and engagement process, digitized web- based geo-narratives and story maps and technical recommendations for culturally-informed schematic designs, sustainable construction methods and low-embodied carbon storing materials. The project process and outcomes will have broad applicability for other vulnerable coastal communities and can be used to support their climate adaptation efforts as well.

Research Team
Principal Investigator: Daniel Abramson, College of Built Environments, Urban Design and Planning, University of Washington
Community Lead: Jamie Judkins, Shoalwater Bay Indian Tribe

University of Washington Partners:
Rob Corser, Associate Professor, Department of Architecture
Julie Kriegh, Affiliate Lecturer, Departments of Construction Management and Architecture and Principal, Kriegh Architecture Studios | Design + Research
Jackson Blalock, Community Engagement Specialist, Washington Sea Grant
Lynne Manzo, Professor, Department of Landscape Architecture
Kristiina Vogt, Professor, School of Environmental and Forest Sciences

Community Partners:
Daniel Glenn, AIA, NCARB, Principal, 7 Directions Architects/Planners 
John David “J.D.” Tovey III, Confederated Tribes of the Umatilla Indian Reservation
Timothy Archer Lehman, Design and Planning Consultant and Lecturer