A Social-Ecological-Infrastructural Systems Framework for Interdisciplinary Study of Sustainable City Systems

Cities are embedded within larger-scale engineered infrastructures (e.g., electric power, water supply, and transportation networks) that convey natural resources over large distances for use by people in cities. The sustainability of city systems therefore depends upon complex, cross-scale interactions between the natural system, the transboundary engineered infrastructures, and the multiple social actors and institutions that govern these infrastructures. These elements, we argue, are best studied in an integrated manner using a novel social-ecological-infrastructural systems (SEIS) framework. In the biophysical subsystem, the SEIS framework integrates urban metabolism with life cycle assessment to articulate transboundary infrastructure supply chain water, energy, and greenhouse gas (GHG) emission footprints of cities. These infrastructure footprints make visible multiple resources (water, energy, materials) used directly or indirectly (embodied) to support human activities in cities. They inform cross-scale and cross-infrastructure sector strategies for mitigating environmental pollution, public health risks and supply chain risks posed to cities. In the social subsystem, multiple theories drawn from the social sciences explore interactions between three actor categories—individual resource users, infrastructure designers and operators, and policy actors—who interact with each other and with infrastructures to shape cities toward sustainability outcomes. Linking of the two subsystems occurs by integrating concepts, theories, laws, and models across environmental sciences/climatology, infrastructure engineering, industrial ecology, architecture, urban planning, behavioral sciences, public health, and public affairs. Such integration identifies high-impact leverage points in the urban SEIS. An interdisciplinary SEIS-based curriculum on sustainable cities is described and evaluated for its efficacy in promoting systems thinking and interdisciplinary vocabulary development, both of which are measures of effective frameworks

Review on City-Level Carbon Accounting

Carbon accounting results for the same city can differ due to differences in protocols, methods, and data sources. A critical review of these differences and the connection among them can help to bridge our knowledge between university-based researchers and protocol practitioners in accounting and taking further mitigation actions. The purpose of this study is to provide a review of published research and protocols related to city carbon accounting, paying attention to both their science and practical actions. To begin with, the most cited articles in this field are identified and analyzed by employing a citation network analysis to illustrate the development of city-level carbon accounting from three perspectives. We also reveal the relationship between research methods and accounting protocols. Furthermore, a timeline of relevant organizations, protocols, and projects is provided to demonstrate the applications of city carbon accounting in practice. The citation networks indicate that the field is dominated by pure-geographic production-based and community infrastructure-based accounting; however, emerging models that combine economic system analysis from a consumption-based perspective are leading to new trends in the field. The emissions accounted for by various research methods consist essentially of the scope 1–3, as defined in accounting protocols. The latest accounting protocols include consumption-based accounting, but most cities still limit their accounting and reporting from pure-geographic production-based and community infrastructure-based perspectives. In conclusion, we argue that protocol practitioners require support in conducting carbon accounting, so as to explore the potential in mitigation and adaptation from a number of perspectives. This should also be a priority for future studies

Understanding subjective well-being: perspectives from psychology and public health

Background Individual subjective well-being (SWB) is essential for creating and maintaining healthy, productive societies. The literature on SWB is vast and dispersed across multiple disciplines. However, few reviews have summarized the theoretical and empirical tenets of SWB literature across disciplinary boundaries. Methods We cataloged and consolidated SWB-related theories and empirical evidence from the fields of psychology and public health using a combination of online catalogs of scholarly articles and online search engines to retrieve relevant articles. For both theories and determinants/correlates of SWB, PubMed, PsychINFO, and Google Scholar were used to obtain relevant articles. Articles for the review were screened for relevance, varied perspectives, journal impact, geographic location of study, and topicality. A core theme of SWB empirical literature was the identification of SWB determinants/correlates, and over 100 research articles were reviewed and summarized for this review. Results We found that SWB theories can be classified into four groups: fulfillment and engagement theories, personal orientation theories, evaluative theories, and emotional theories. A critical analysis of the conflicts and overlaps between these theories reveals the lack of a coherent theoretical and methodological framework that would make empirical research systematically comparable. We found that determinants/correlates of SWB can be grouped into seven broad categories: basic demographics, socioeconomic status, health and functioning, personality, social support, religion and culture, and geography and infrastructure. However, these are rarely studied consistently or used to test theories. Conclusions The lack of a clear, unifying theoretical basis for categorizing and comparing empirical studies can potentially be overcome using an operationalizable criterion that focuses on the dimension of SWB studied, measure of SWB used, design of the study, study population, and types of determinants and correlates. From our review of the empirical literature on SWB, we found that the seven categories of determinants/correlates identified may potentially be used to improve the link between theory and empirical research, and that the overlap in the determinant/correlates as they relate to multiple theory categories may enable us to test theories in unison. However, doing so in the future would require a conscious effort by researchers in several areas, which are discussed

Episode 12: Circular Economies and Low-Carbon Urban Infrastructure Planning

Runtime 13:14What is the unique role that urban infrastructure planning can play in national carbon mitigation? In this podcast, Anu Ramaswami, professor at the Humphrey School of Public Affairs, discusses how cities are positioned to plan infrastructure systems using circular economy principles that reduce material and energy reuse across sectors to deliver a low-carbon future

Episode 13: All-city Carbon Emissions: Understanding City Types and Impact

Runtime 10:08It is common practice to consider the carbon emissions of single cities. But what happens when you analyze carbon emissions for all cities in a country using nationally aligned data? In this podcast, Anu Ramaswami, professor at the Humphrey School of Public Affairs, discusses how all-city analysis can reveal “city types” that help inform carbon policy and action

Episode 11: Local Health Co-Beenfits of Urban Climate Action

Runtime 08:55Reducing carbon emissions across multiple urban infrastructure sectors can yield significant local air pollution related health co-benefits. But cities will see and experience these co-benefits in different ways and to different degrees. In this podcast, Anu Ramaswami, professor at the Humphrey School of Public Affairs, discusses the emerging science around how to connect global carbon reduction actions to city-specific health outcomes

What Is the Contribution of City-Scale Actions to the Overall Food System’s Environmental Impacts?: Assessing Water, Greenhouse Gas, and Land Impacts of Future Urban Food Scenarios

This paper develops a methodology for individual cities to use to analyze the in- and trans-boundary water, greenhouse gas (GHG), and land impacts of city-scale food system actions. Applied to Delhi, India, the analysis demonstrates that city-scale action can rival typical food policy interventions that occur at larger scales, although no single city-scale action can rival in all three environmental impacts. In particular, improved food-waste management within the city (7% system-wide GHG reduction) matches the GHG impact of preconsumer trans-boundary food waste reduction. The systems approach is particularly useful in illustrating key trade-offs and co-benefits. For instance, multiple diet shifts that can reduce GHG emissions have trade-offs that increase water and land impacts. Vertical farming technology (VFT) with current applications for fruits and vegetables can provide modest system-wide water (4%) and land reductions (3%), although implementation within the city itself may raise questions of constraints in water-stressed cities, with such a shift in Delhi increasing community-wide direct water use by 16%. Improving the nutrition status for the bottom 50% of the population to the median diet is accompanied by proportionally smaller increases of water, GHG, and land impacts (4%, 9%, and 8%, systemwide): increases that can be offset through simultaneous city-scale actions, e.g., improved food-waste management and VFT

Exploring income and racial inequality in preparedness for Hurricane Ida (2021): insights from digital footprint data

Preparedness for adverse events is critical to building urban resilience to climate-related risks. While most extant studies investigate preparedness patterns based on survey data, this study explores the potential of big digital footprint data (i.e. population visits to points of interest (POI)) to investigate preparedness patterns in the real case of Hurricane Ida (2021). We further investigate income and racial inequality in preparedness by combining the digital footprint data with demographic and socioeconomic data. A clear pattern of preparedness was seen in Louisiana with aggregated visits to grocery stores, gasoline stations, and construction supply dealers increasing by nearly 9%, 12%, and 10% respectively, representing three types of preparedness: survival, mobility planning, and hazard mitigation. Preparedness for Hurricane Ida was not seen in New York and New Jersey states. Inequality analyses for Louisiana across census block groups (CBGs) demonstrate that CBGs with higher income have more (nearly 8% greater) preparedness in visiting gasoline stations, while CBGs with a larger percentage of the white population have more preparedness in visiting grocery stores (nearly 12% more) in the lowest income groups. The results indicate that income and racial inequality differ across different preparedness in terms of visiting different POIs

Energy-use benchmarks for the case-study cities

<p><b>Table 1.</b>  Energy-use benchmarks for the case-study cities. Comparative state-level benchmark shown in <em>[bracket]</em>. (Note: <em>energy-use data</em>: local retrieved from bottom-up data (ICLEI <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib23" target="_blank">2010</a>), state retrieved from (EIA <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib14" target="_blank">2012</a>); <em>employment statistics</em>: local retrieved from (MIG <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib28" target="_blank">2010</a>), state retrieved from (Census <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib6" target="_blank">2011</a>); <em>population and households</em>: local retrieved from (MIG <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib28" target="_blank">2010</a>), state retrieved from (Census <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib6" target="_blank">2011</a>); <em>vehicles miles traveled (VMT)</em>: local retrieved from (ICLEI <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib23" target="_blank">2010</a>), state retrieved from (FHWA <a href="http://iopscience.iop.org/1748-9326/8/3/035011/article#erl463816bib16" target="_blank">2008</a>).) </p> <p><strong>Abstract</strong></p> <p>Three broad approaches have emerged for energy and greenhouse gas (GHG) accounting for individual cities: (a) purely in-boundary source-based accounting (IB); (b) community-wide infrastructure GHG emissions footprinting (CIF) incorporating life cycle GHGs (in-boundary plus trans-boundary) of key infrastructures providing water, energy, food, shelter, mobility–connectivity, waste management/sanitation and public amenities to support community-wide activities in cities—all resident, visitor, commercial and industrial activities; and (c) consumption-based GHG emissions footprints (CBF) incorporating life cycle GHGs associated with activities of a sub-set of the community—its final consumption sector dominated by resident households. The latter two activity-based accounts are recommended in recent GHG reporting standards, to provide production-dominated and consumption perspectives of cities, respectively. Little is known, however, on how to normalize and report the different GHG numbers that arise for the same city. We propose that CIF and IB, since they incorporate production, are best reported per unit GDP, while CBF is best reported per capita. Analysis of input–output models of 20 US cities shows that GHG^CIF/GDP is well suited to represent differences in urban energy intensity features across cities, while GHG^CBF/capita best represents variation in expenditures across cities. These results advance our understanding of the methods and metrics used to represent the energy and GHG performance of cities.</p