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Municipalities face the direct impact of climate change events, but many are challenged to assess the potential outcomes of future climate action policies. It is essential for local municipalities to be able to evaluate cross-sector and cross-scale policy interventions, but many lack the expertise and resources for wholistic forecasting. This paper used a hybrid interscalar and interdisciplinary modeling approach to evaluate, compare, visualize, and reveal the performance of climate actions at building and neighbourhood scales of future 'what-if' scenarios for three neighbourhood urban form types (dispersed, corridor, nodal) in three cities in British Columbia, Canada (Vancouver, Victoria, Prince George). Results found that increases in population density combined with strict building standards and retrofitting older buildings decreased per person emissions per year by up to 84% by 2050. Within the neighbourhoodscale areas, building form and location had less impact. Population density and frequency of transit service were most important for mobility mode shifts. Concentrating density at transit nodes or along commercial corridors improved the percentages of residents within a fiveminute walk of those services, but proximity to greenspaces showed mixed results. [ABSTRACT FROM AUTHOR]

Spatial relations among urban elements (buildings, streets, etc.) constantly affect the quality of urban spaces, creating more or less livable cities. The study of urban form has been a way of objectively quantifying such relations to understand their dynamics. Urban livability is the ability of urban spaces to fulfill the expectations of its inhabitants for wellbeing and quality of life. Measurable spatial patterns underlie the emergence of livable cities. Still, few researchers have considered if and how these patterns affect socioeconomic conditions across spatial scales. This paper explores the relationships between indicators of socioeconomic livability and cross-scale patterns of demographic and morphological densities within the Metro Vancouver (MV) region (Canada). Indicators of accessibility, social diversity, affordability, and economic vitality were quantified and compared among five population density clusters composed of 3450 census dissemination areas (DAs) in MV. Morphological indicators of intensity, centrality and diversity were aggregated at the DAs using spatial network analysis with five radii from 400 to 4800 m. Socioeconomic indices were regressed on urban form variables to assess the importance of the built environment on predicting livability-related qualities. Overall, indicators of the intensity of urban form were the most significant to predict the socioeconomic metrics. [ABSTRACT FROM AUTHOR]

If a neighbourhood is designed and built according to best practices for walkable neighbourhood design, will people respond and walk in the public realm? This was a narrowly focused case study of a brownfield redevelopment in Vancouver, Canada, intentionally designed to be highly walkable. Methods included a Walk Score® analysis, both in-person and video observational studies of people using three public spaces over a nine-month period, supplemented with questionnaires. Observational studies and questionnaires revealed high numbers of people using the public spaces for walking and active mobility throughout the year in all weather conditions, validating a very high Walk Score®. However, the study also uncovered unexpected patterns of walking and motivations for walking, which reveals the value of post-occupancy observational and survey studies to fully understand how specific attributes of the neighbourhood landscape may significantly change what people value and how they use the public realm. [ABSTRACT FROM AUTHOR]

Design students are increasingly seeking precedent information through web-based digital archives of design cases. Little is known, however, about the use, relative merits or opportunities of digital cases as a knowledge source for design students. This paper uses a study of web-based urban design reference tools to examine new opportunities for using precedents in urban design. The research includes focus groups, content analysis of student work and an auto-ethnography by one of the authors to examine student use of the reference tools in 3 urban design studios in planning and landscape architecture. Students used 3-D digital models of precedents to review, replicate, revise, reshape and recreate elements of urban design in an environment of accelerated learning. [Copyright &y& Elsevier]

Climate change, environmental degradation, and failing infrastructure are only some factors driving many cities toward adopting policies for more sustainable development. Do the resulting developments return the promised benefits? This paper evaluates one such sustainable development, most notable for its mandate to protect downstream salmon habitat despite being a high-density, high elevation development. At five years old and 39% complete, UniverCity in Vancouver, Canada has achieved some measures of a sustainable neighborhood. It is a walkable and compact neighborhood that has mitigated some urban runoff impacts. While the development has not yet achieved its high goals for “no net impact” on downstream habitat, the development team is monitoring performance and adapting designs and management over time. [ABSTRACT FROM AUTHOR]

Urban forests are gaining recognition as a nature-based solution to climate change and other social-environmental issues in cities. Yet, the integration of urban forests may conflict with other climate measures such as urban densification, which may create hostile growing conditions for trees and lead to tree decline or loss. While previous studies have identified conflicts between densification and urban forests, there is a lack of research mapping the relationships among climate action, urban planning, and urban forest policies. This study involved semi-structured interviews with 14 key informants in Metro Vancouver, Canada, a rapidly-densifying region. Twenty-six trade-offs and 24 synergies were identified in five areas/sectors, such as (re)development and infrastructure. While strategic policies often highlighted synergies, policy implementation processes and outcomes often encountered trade-offs due to factors such as limited budgets and low political priority. Notably, most trade-offs and synergies were found in the same areas - (re)development and infrastructure - and shared the same contributing factors, such as political priority of urban forestry, suggesting areas of opportunity to transform trade-offs into synergies through appropriate planning and monitoring. The study also highlighted the need for further research on the interactions and impacts among municipal policies for more effective implementation and outcomes. • The study is among the first attempts to explore policy interactions on climate action, urban planning, and urban forest. • Semi-structured interviews were conducted with key informants with relevant expertise in cities of Metro Vancouver, Canada. • Results revealed key trade-offs and synergies among policies and practices, especially in development and infrastructure. • Connections between trade-offs and synergies suggest opportunities for compact, climate-proofed, and green cities. [ABSTRACT FROM AUTHOR]

Background: Urban forests are increasingly recognized as important tools in climate change mitigation and adaptation, prompting many cities to set tree canopy cover targets. However, current gaps in knowledge include understanding relationships and the feasibility of maximizing benefits between urban greening and other climate actions, such as densification. This study offers a data-driven and manageable framework for assessing current and anticipated future urban forestry conditions using spatial tree and built-form models. Methods: We spatially modelled 4 planting scenarios for increasing tree canopy cover by 2050 in a densifying neighbourhood in Vancouver, Canada, with low (< 10%) existing tree canopy. Results: Based on mortality assumptions, we aged out and replaced 1,853 to 2,445 trees since 2020. We added 6,079 to 11,726 trees across the 4 scenarios (10,228 to 15,823 total), increasing canopy cover from 7% in 2020 to a maximum of 16% by 2050. Despite rigorous tree planting, we were unable to achieve a 30% canopy cover target at neighbourhood scale. Tree replacement due to mortality was a major contributor to decreased canopy cover and volume in future scenarios. The 31% to 34% reduction in future canopy cover due to the replacement of aged-out trees was driven by changes on private parcels. Conclusion: Our systematic framework for generating and spatially modelling trees in a simulated future neighbourhood provides an opportunity for iteratively assessing multiple potential tree planting configurations. Future work for this project includes investigating social-ecological, outdoor shading, and building energy implications of various modelled urban forest strategies. [ABSTRACT FROM AUTHOR]

Background: Urban forests can provide nature-based solutions (NBS) to complex climate-change challenges via the provision of ecosystem services such as shade and cooling that offset increased risks of chronic diseases and excess mortality. They also confer indirect health benefits by providing regulating ecosystem services that can facilitate climate-change mitigation efforts: increased shade can encourage shifts to lower-carbon transportation methods such as walking and cycling, for example. However, in order to ensure that urban forests are both resilient to threats and confer the maximum possible benefits, we must be able to project decades into the future in order to understand the implications of current urban forestry decisions. Methods: This study outlines a framework for creating urban-forest scenario models and reports the results of a case study conducted to highlight the ways in which decisions made at each stage of the scenario-development process impact its outcomes and application. Our case study focused on a neighbourhood in Vancouver, Canada, that is simultaneously undergoing urban densification and aiming to significantly increase canopy cover by 2050. Three distinct aims were identified for the case study: maximizing publichealth benefits, selecting climate-resilient tree species, and integrating planting across public and private lands to advance diversity. To achieve these aims, baseline information on the neighbourhood's existing tree network was collected, entered into GIS software, and delineated based on a set of pre-identified characteristics. Next, a list of climate-adapted species was developed. This climate-adapted species list was then virtually "planted" across the neighbourhood, using a combination of machine-based and manual planting techniques. Finally, the resulting scenario model was quantitatively assessed to understand its composition and impacts. Results: Our study demonstrates that a salubrious, resilient, and diverse urban forest can be created via a strategic program that complements extant trees in the public domain with planting programs along blue-green streets and on private property. Conclusions: Achieving the urban tree trifecta will require collaboration among municipal departments and the development of a range of public and private initiatives, but it has the potential to maximize nature-based solutions in cities facing rapid shifts due to densification and climate change. [ABSTRACT FROM AUTHOR]

As urban heatwaves become more severe, frequent and longer, cities seek adaptive building cooling measures. Although passive building design, energy-efficient materials and technologies and mechanical means are proven cooling methods, the potential of naturebased solutions (particularly trees as shading elements) has been understudied despite its significant opportunity. Using a new framework to explore this at the neighbourhood level, three future (2050) potential tree planting strategies are modelled for increasing tree volume and canopy cover and their impacts assessed for summer building-level solar radiation absorption (SRA) and building cooling energy demand (BCED) for a densifying neighbourhood in Vancouver, Canada. The boldest tree planting strategy, with 287% more trees than baseline and 16% canopy cover, reduced neighbourhood-scale total SRA (22%) and BCED (48%) over a no-trees scenario. BCED reductions of up to 64% for retrofitted/redeveloped buildings and 53-79% for low/medium-height buildings (mostly single-family residential) were associated with targeted south-side tree planting. Taller/larger buildings (predominantly mixed use) and buildings along north-south-oriented streets (mainly commercial and mixed use) encountered more tree shading challenges and would require more site-specific interventions. The methodology presented provides a framework to assess current and potential future shading and cooling energy benefits through various tree planting strategies. [ABSTRACT FROM AUTHOR]

Background: Cities consume a disproportionate amount of energy for internal temperature regulation. Being able to reduce cities' cooling load on hot summer days can decrease energy consumption while improving occupants' thermal comfort. The urban canopy is an effective shading agent, adding cooling benefits to existing buildings and streets while providing other ecological and physiological values. Yet the building and street shading dynamic is a highly complex system that involves micro-level building components and macro-level variables. Introducing urban canopy to such a complex system creates another challenge, as urban canopy variables can also interact with buildings at both micro- and macro-levels. In order to accurately represent the urban canopy shading effect, it is necessary to account for the interactions among buildings, streets, and urban canopies. Methods: This study simulates the shading effect of urban canopy measured by aerial laser scanning (ALS) in the City of Vancouver, Canada, through the integration of a Radiance daylight simulation engine and geographic information system (GIS) data. All trees detected by ALS were included in the analysis. Results: The results indicate that street surfaces receive more solar irradiance reduction than building roofs and façades (i.e., exterior walls). Neighborhoods with less density and lower buildings were shaded noticeably better than areas with higher density and taller buildings. Among Vancouver's 22 neighborhoods, 2 neighborhoods, Kitsilano and the West End, demonstrated a promising sign where both building density/height and urban canopies are maintained. There was evidence of high canopy shading and high-density urban morphologies. Conclusion: Overall, this work provided an authentic canopy assessment from single building to city scale, creating opportunities to investigate intracity urban canopy variations, equality, and the balance between urban greening and urban densification. [ABSTRACT FROM AUTHOR]

A proliferation of energy models has been developed across disciplines to explore energy and greenhouse gas (GHG) emissions-reduction strategies in cities. Hybrid models are especially useful because they incorporate more dynamics to simulate realistic results informed by relevant high-level policy decisions and building-level factors. Spatial and aspatial energy models, however, are not often linked, which overlooks the spatial impact of energy and emissions policies in urban environments. A new method is presented that links these types of models to understand how building stocks change over time in response to policies. This approach integrates outputs from an aspatial economic model, CIMS, with buildings in a spatially explicit urban building energy model (UBEM), UMI. The energy-economy model is parameterised against the UBEM using identified baseline condition and proposed future policy interventions. Building stock replacement and retrofit change are downscaled and disaggregated to individual buildings based on existing stock age and a probability-based Markov chain model (MCM). This integration enables simulations of cross-scale policy interventions that are sensitive to both economically and mechanically driven factors. An application of this approach shows how it can be used to evaluate how different policies interact with and influence building energy demand and GHG emissions. [ABSTRACT FROM AUTHOR]

Many cities in Canada and the US are deploying smart growth planning to counter urban sprawl, to increase transportation options and to reduce greenhouse gas (GHG) emissions. However many cities neglect to assess whether the growth required for achieving increased density would lead to overall reductions in municipal emissions. Our study conducts this assessment by examining the potential impact of development that conforms to a form-based code in Revelstoke, British Columbia. Like every city in British Columbia, Revelstoke has set GHG emissions reductions targets and has specifically identified compact development as facilitated by a form-based code as a mechanism for achieving targets. Using a number of different data sources ranging from municipal to parcel scales we constructed a neighbourhood specific GHG inventory and tested twelve design scenarios in one of the Revelstoke's identified neighbourhood centres. Our study examined how increasing density to thresholds that would enable both transportation mode shifts and the adoption of district energy systems, would affect municipal level GHG emissions. While we found opportunities for significantly reducing per capita emissions in the denser neighbourhoods, Revelstoke' s total GHG emissions would increase even under the highest density scenarios. his work has broader implications for the capacity of compact development to reduce emissions without a simultaneous decommissioning of sprawling high emitting neighbourhoods. [ABSTRACT FROM AUTHOR]