The Effects of Historical Housing Policies on Resident Exposure to Intra-Urban Heat: A Study of 108 US Urban Areas

Evidence-based guidance on reflective pavement for urban heat mitigation in Arizona

Urban overheating is an increasing threat to people, infrastructure, and the environment. Common heat mitigation strategies, such as green infrastructure, confront space limitations in current car-centric cities. In 2020, the City of Phoenix, Arizona, piloted a "cool pavement" program using a solar reflective pavement seal on 58 km of residential streets. Comprehensive micrometeorological observations are used to evaluate the cooling potential of the reflective pavement based on three heat exposure metrics-surface, air, and mean radiant temperatures-across three residential reflective pavement-treated and untreated neighborhoods. In addition, the solar reflectivity of reflective pavement is observed over 7 months across eight residential neighborhoods. Results are synthesized with the literature to provide context-based reflective pavement implementation guidelines to mitigate urban overheating where common strategies cannot be applied. The three most important contextual factors to consider for effective implementation include urban location, background climate type, and heat exposure metric of interest.

EASIUR-HR: A Model To Evaluate Exposure Inequality Caused by Ground-Level Sources of Primary Fine Particulate Matter

People of color disproportionately bear the health impacts of air pollution, making air quality a critical environmental justice issue. However, quantitative analysis of the disproportionate impacts of emissions is rarely done due to a lack of suitable models. Our work develops a high-resolution reduced-complexity model (EASIUR-HR) to evaluate the disproportionate impacts of ground-level primary PM_2.5 emissions. Our approach combines a Gaussian plume model for near-source impacts of primary PM_2.5 with a previously developed reduced-complexity model, EASIUR, to predict primary PM_2.5 concentrations at a spatial resolution of 300 m across the contiguous United States. We find that low-resolution models underpredict important local spatial variation of air pollution exposure to primary PM_2.5 emissions, potentially underestimating the contribution of these emissions to national inequality in PM_2.5 exposure by more than a factor of 2. We apply EASIUR-HR to analyze the impacts of vehicle electrification on exposure disparities. While such a policy has small aggregate air quality impacts nationally, it reduces exposure disparity for race/ethnic minorities. Our high-resolution RCM for primary PM_2.5 emissions (EASIUR-HR) is a new, publicly available tool to assess inequality in air pollution exposure across the United States.

Exposure to infection when accessing groceries reveals racial and socioeconomic inequities in navigating the pandemic

Disasters often create inequitable consequences along racial and socioeconomic lines, but a pandemic is distinctive in that communities must navigate the ongoing hazards of infection exposure. We examine this for accessing essential needs, specifically groceries. We propose three strategies for mitigating risk when accessing groceries: visit grocery stores less often; prioritize generalist grocery stores; seek out stores whose clientele have lower infection rates. The study uses a unique combination of data to examine racial and socioeconomic inequities in the ability to employ these strategies in the census block groups of greater Boston, MA in April 2020, including cellphone-generated GPS records to observe store visits, a resident survey, localized infection rates, and demographic and infrastructural characteristics. We also present an original quantification of the amount of infection risk exposure when visiting grocery stores using visits, volume of visitors at each store, and infection rates of those visitors' communities. Each of the three strategies for mitigating exposure were employed in Boston, though differentially by community. Communities with more Black and Latinx residents and lower income made relatively more grocery store visits. This was best explained by differential use of grocery delivery services. Exposure and exposure per visit were higher in communities with more Black and Latinx residents and higher infection rates even when accounting for strategies that diminish exposure. The findings highlight two forms of inequities: using wealth to transfer risk to others through grocery deliveries; and behavioral segregation by race that makes it difficult for marginalized communities to avoid hazards.

Women's mental health and climate change Part II: Socioeconomic stresses of climate change and eco-anxiety for women and their children

Climate change is a significant public health crisis that is both rooted in pre-existing inequitable socioeconomic and racial systems and will further worsen these social injustices. In the face of acute and slow-moving natural disasters, women, and particularly women of color, will be more susceptible to gender-based violence, displacement, and other socioeconomic stressors, all of which have adverse mental health outcomes. Among the social consequences of climate change, eco-anxiety resulting from these negative impacts is also increasingly a significant factor in family planning and reproductive justice, as well as disruptions of the feminine connection to nature that numerous cultures historically and currently honor. This narrative review will discuss these sociologic factors and also touch on ways that practitioners can become involved in climate-related advocacy for the physical and mental well-being of their patients.

Current street tree communities reflect race-based housing policy and modern attempts to remedy environmental injustice

Humans promote and inhibit other species on the urban landscape, shaping biodiversity patterns. Institutional racism may underlie the distribution of urban species by creating disproportionate resources in space and time. Here, we examine whether present-day street tree occupancy, diversity, and composition in Baltimore, MD, USA, neighborhoods reflect their 1937 classification into grades of loan risk-from most desirable (A = green) to least desirable (D = "redlined")-using racially discriminatory criteria. We find that neighborhoods that were redlined have consistently lower street tree α-diversity and are nine times less likely to have large (old) trees occupying a viable planting site. Simultaneously, redlined neighborhoods were locations of recent tree planting activities, with a high occupancy rate of small (young) trees. However, the community composition of these young trees exhibited lower species turnover and reordering across neighborhoods compared to those in higher grades, due to heavy reliance on a single tree species. Overall, while the negative effects of redlining remain detectable in present-day street tree communities, there are clear signs of recent investment. A strategy of planting diverse tree cohorts paired with investments in site rehabilitation and maintenance may be necessary if cities wish to overcome ecological feedbacks associated with legacies of environmental injustice.

Neighborhood Walkability, Historical Redlining, and Childhood Obesity in Denver, Colorado

Childhood obesity is a precursor to future health complications. In adults, neighborhood walkability is inversely associated with obesity prevalence. Recently, it has been shown that current urban walkability has been influenced by historical discriminatory neighborhood disinvestment. However, the relationship between this systemic racism and obesity has not been extensively studied. The objective of this study was to evaluate the association of neighborhood walkability and redlining, a historical practice of denying home loans to communities of color, with childhood obesity. We evaluated neighborhood walkability and walkable destinations for 250 participants of the Healthy Start cohort, based in the Denver metropolitan region. Eligible participants attended an examination between ages 4 and 8. Walkable destinations and redlining geolocations were determined based on residential addresses, and a weighting system for destination types was developed. Sidewalks and trails in Denver were included in the network analyst tool in ArcMap to calculate the precise walkable environment for each child. We implemented linear regression models to estimate associations between neighborhood characteristics and child body mass index (BMI) z-scores and fat mass percent. There was a significant association between child BMI and redlining (β: 1.36, 95% CI: 0.106, 2.620). We did not find an association between walkability measures and childhood obesity outcomes. We propose that cities such as Denver pursue built environment policies, such as inclusionary zoning and direct investments in neighborhoods that have been historically neglected, to reduce the childhood health impacts of segregated poverty, and suggest further studies on the influences that redlining and urban built environment factors have on childhood obesity.

The mental health of women and climate change: Direct neuropsychiatric impacts and associated psychological concerns

Climate change brings exposures to heat, air pollution, poorer quality food, and infectious disease that have significant direct effects on women and their mental health. These environmental impacts are multifaceted in their consequences and raise risks of depression, suicide, violent victimization, post-traumatic stress disorder, and various other neuropsychiatric symptoms. Women also suffer increased climate psychological risks from higher rates of stillbirth, preterm birth, and developmental problems in their children. Here we review what is known about the overlap of women's individual mental health and climate change, and highlight areas where more research is needed.

The intersection of pediatric surgery, climate change, and equity

Climate change is occurring at an unprecedented rate. Recent years have seen heatwaves, wildfires, floods, droughts, and re-emerging infectious diseases fueled by global warming. Global warming has also increased the frequency and severity of surgical disease, particularly for children, who bear an estimated 88% of the global burden of disease attributable to climate change. Health care delivery itself weighs heavily on the environment, accounting for nearly 5% of global greenhouse gas emissions. Within the health care sector, surgery and anesthesia are particularly carbon intensive. The surgical community must prioritize the intersection of climate change and pediatric surgery in order to address pediatric surgical disease on a global scale, while reducing the climate impact of surgical care delivery. This review defines the current state of climate change and its effects on pediatric surgical disease, discusses climate justice, and outlines actions to reduce the climate impact of surgical services. LEVEL OF EVIDENCE: Level V.

Historic redlining and the siting of oil and gas wells in the United States

BACKGROUND

The presence of active or inactive (i.e., postproduction) oil and gas wells in neighborhoods may contribute to ongoing pollution. Racially discriminatory neighborhood security maps developed by the Home-Owners Loan Corporation (HOLC) in the 1930s may contribute to environmental exposure disparities.

OBJECTIVE

To determine whether receiving worse HOLC grades was associated with exposure to more oil and gas wells.

METHODS

We assessed exposure to oil and gas wells among HOLC-graded neighborhoods in 33 cities from 13 states where urban oil and gas wells were drilled and operated. Among the 17 cities for which 1940 census data were available, we used propensity score restriction and matching to compare well exposure neighborhoods that were similar on observed 1940 sociodemographic characteristics but that received different grades.

RESULTS

Across all included cities, redlined D-graded neighborhoods had 12.2 ± 27.2 wells km-2, nearly twice the density in neighborhoods graded A (6.8 ± 8.9 wells km-2). In propensity score restricted and matched analyses, redlined neighborhoods had 2.0 (1.3, 2.7) more wells than comparable neighborhoods with a better grade.

SIGNIFICANCE

Our study adds to the evidence that structural racism in federal policy is associated with the disproportionate siting of oil and gas wells in marginalized neighborhoods.

Historic Redlining Practices and Contemporary Determinants of Health in the Detroit Metropolitan Area

Objectives. To examine how redlining, a historical racially discriminatory housing policy implemented by the Home Owners' Loan Corporation (HOLC), is associated with current neighborhood determinants of health in the Detroit Metropolitan Area. Methods. We analyzed associations between census tract‒level HOLC color grades (red = "hazardous"; yellow = "declining"; blue = "desirable"; and green = "best") and a developed neighborhood determinants of health index (DOHI) consisting of 8 indicators of economic, social, governance, and physical environment characteristics using spatial regression analysis and controlling for change in the census tract's percentage of White residents. Results. A total of 484 Detroit Metropolitan Area census tracts had HOLC grades. The mean redlining score across all census tracts was 3.02 (min = 1.0; max = 4.0). The mean contemporary DOHI was 19.11 (min = 8.0; max = 36.0). Regression models show significantly higher DOHI scores in yellowlined (b = 2.71; 95% confidence interval [CI] = 1.52, 3.91), bluelined (b = 5.33; 95% CI = 3.65, 7.01), and greenlined (b = 9.25; 95% CI = 6.86, 11.64) neighborhoods compared with redlined neighborhoods. Conclusions. Historical redlined neighborhoods experience contemporary determinants of health conditions that are less conducive to health compared with those in nonredlined neighborhoods. These differences also reflect the accumulation of resources essential for health in greenlined neighborhoods. Public Health Implications. Neighborhood development initiatives should consider the impacts of historical redlining on contemporary neighborhood conditions. (Am J Public Health. 2023;113(S1): S49-S57. https://doi.org/10.2105/AJPH.2022.307162).

Association of Area-Level Heat and Social Vulnerability With Recurrent Hospitalizations Among Individuals With Rheumatic Conditions

OBJECTIVE

Climate and social vulnerability contribute to morbidity and health care utilization. We examined associations between the neighborhood Social Vulnerability Index (SVI) and the Heat Vulnerability Index (HVI) and recurrent hospitalizations among individuals with rheumatic conditions.

METHODS

Using a Massachusetts multihospital centralized clinical data repository, we identified individuals ≥18 years of age with a rheumatic condition who received rheumatology care within 3 years of April 2021. We defined the index date as 2 years before the last encounter and the baseline period as 1 year pre-index date. Addresses were geocoded and linked by census tract to the SVI and the HVI. We used multilevel, multinomial logistic regression to examine the odds of 1-3 and ≥4 hospitalizations (reference = 0) over 2 years post index date by vulnerability index, adjusting for age, gender, race/ethnicity, insurance, and comorbidities.

RESULTS

Among 14,401 individuals with rheumatic conditions, the mean ± age was 61.9 ± 15.7 years, 70% were female, 79% White, 7% Black, and 2% Hispanic. There were 8,251 hospitalizations; 11,649 individuals (81%) had 0 hospitalizations, 2,063 (14%) had 1-3, and 689 (5%) had ≥4. Adjusting for individual-level factors, individuals living in the highest versus lowest SVI areas had 1.84 times higher odds (95% confidence interval [95% CI] 1.43-2.36) of ≥4 hospitalizations. Individuals living in the highest versus lowest HVI areas had 1.64 times greater odds (95% CI 1.17-2.31) of ≥4 hospitalizations.

CONCLUSION

Individuals with rheumatic conditions living in areas with high versus low social and heat vulnerability had significantly greater odds of recurrent hospitalizations. Studies are needed to determine modifiable factors to mitigate risks.

Mixed methods assessment of personal heat exposure, sleep, physical activity, and heat adaptation strategies among urban residents in the Boston area, MA

The growing frequency, intensity, and duration of extreme heat events necessitates interventions to reduce heat exposures. Local opportunities for heat adaptation may be optimally identified through collection of both quantitative exposure metrics and qualitative data on perceptions of heat. In this study, we used mixed methods to characterize heat exposure among urban residents in the area of Boston, Massachusetts, US, in summer 2020. Repeated interviews of N = 24 study participants ascertained heat vulnerability and adaptation strategies. Participants also used low-cost sensors to collect temperature, location, sleep, and physical activity data. We saw significant differences across temperature metrics: median personal temperature exposures were 3.9 °C higher than median ambient weather station temperatures. Existing air conditioning (AC) units did not adequately control indoor temperatures to desired thermostat levels: even with AC use, indoor maximum temperatures increased by 0.24 °C per °C of maximum outdoor temperature. Sleep duration was not associated with indoor or outdoor temperature. On warmer days, we observed a range of changes in time-at-home, expected given our small study size. Interview results further indicated opportunities for heat adaptation interventions including AC upgrades, hydration education campaigns, and amelioration of energy costs during high heat periods. Our mixed methods design informs heat adaptation interventions tailored to the challenges faced by residents in the study area. The strength of our community-academic partnership was a large part of the success of the mixed methods approach.

Redlining and Neighborhood Walking in Older Adults: The 2017 National Household Travel Survey

INTRODUCTION

In the 1930s, Black, working-class, and immigrant neighborhoods were color coded on maps (i.e., redlining) indicating investment risk, which negatively impacted mortgage attainment/homeownership for these groups and led to long-standing segregation by race/ethnicity and socioeconomic status. Limited studies have investigated the health impacts of redlining, particularly among older adults who tend to stay closer to their residences. This study examines whether older adults in historically redlined neighborhoods report less neighborhood walking and whether associations vary by race/ethnicity and income.

METHODS

The sample included 4,651 individuals aged ≥65 years from the 2017 U.S. National Household Travel Survey. U.S. Census tract‒based redlining scores were 1=best, 2=still desirable, 3=definitely declining, and 4=hazardous. Multivariable negative binomial regression tested the associations between redlining and neighborhood walking/day in the overall sample and with stratification by poverty status (analyzed in 2022).

RESULTS

Participants were on average aged 73 years, and 11% were African/American Black, 75% were White, 8% were Hispanic/Latinx, and 6% were of other race/ethnicity. Participants reported a mean of 7.1 neighborhood walking minutes/day (SD=20.6), and 60% lived in definitely declining or hazardous neighborhoods. Individuals in hazardous neighborhoods (versus those in best neighborhoods) reported less neighborhood walking (prevalence ratio=0.64; 95% CI=0.43, 0.97). Among those living in poverty, living in definitely declining and hazardous neighborhoods was associated with less neighborhood walking (prevalence ratio=0.39 [95% CI=0.20, 0.79] and 0.39 [95% CI=0.18, 0.82], respectively).

CONCLUSIONS

Less neighborhood walking was reported among individuals living in neighborhoods with a historic redlining score of definitely declining or hazardous. Future studies using larger, more diverse cohorts may elucidate whether associations differ by race/ethnicity and geographic location/city.

Residential and Race/Ethnicity Disparities in Heat Vulnerability in the United States

Adverse health outcomes caused by extreme heat represent the most direct human health threat associated with the warming of the Earth's climate. Socioeconomic, demographic, health, land cover, and temperature determinants contribute to heat vulnerability; however, nationwide patterns of residential and race/ethnicity disparities in heat vulnerability in the United States are poorly understood. This study aimed to develop a Heat Vulnerability Index (HVI) for the United States; to assess differences in heat vulnerability across geographies that have experienced historical and/or contemporary forms of marginalization; and to quantify HVI by race/ethnicity. Principal component analysis was used to calculate census tract level HVI scores based on the 2019 population characteristics of the United States. Differences in HVI scores were analyzed across the Home Owners' Loan Corporation (HOLC) "redlining" grades, the Climate and Economic Justice Screening Tool (CEJST) disadvantaged versus non-disadvantaged communities, and race/ethnicity groups. HVI scores were calculated for 55,267 U.S. census tracts. Mean HVI scores were 17.56, 18.61, 19.45, and 19.93 for HOLC grades "A"-"D," respectively. CEJST-defined disadvantaged census tracts had a significantly higher mean HVI score (19.13) than non-disadvantaged tracts (16.68). The non-Hispanic African American or Black race/ethnicity group had the highest HVI score (18.51), followed by Hispanic or Latino (18.19). Historically redlined and contemporary CEJST disadvantaged census tracts and communities of color were found to be associated with increased vulnerability to heat. These findings can help promote equitable climate change adaptation policies by informing policymakers about the national distribution of place- and race/ethnicity-based disparities in heat vulnerability.

Climate change and the prevention of cardiovascular disease

Climate change is a worsening global crisis that will continue negatively impacting population health and well-being unless adaptation and mitigation interventions are rapidly implemented. Climate change-related cardiovascular disease is mediated by air pollution, increased ambient temperatures, vector-borne disease and mental health disorders. Climate change-related cardiovascular disease can be modulated by climate change adaptation; however, this process could result in significant health inequity because persons and populations of lower socioeconomic status have fewer adaptation options. Clear scientific evidence for climate change and its impact on human health have not yet resulted in the national and international impetus and policies necessary to slow climate change. As respected members of society who regularly communicate scientific evidence to patients, clinicians are well-positioned to advocate on the importance of addressing climate change. This narrative review summarizes the links between climate change and cardiovascular health, proposes actionable items clinicians and other healthcare providers can execute both in their personal life and as an advocate of climate policies, and encourages communication of the health impacts of climate change when counseling patients. Our aim is to inspire the reader to invest more time in communicating the most crucial public health issue of the 21st century to their patients.

The Relationship of Historical Redlining with Present-Day Neighborhood Environmental and Health Outcomes: A Scoping Review and Conceptual Model

Following the Great Depression and related home foreclosures, the federal government established new agencies to facilitate access to affordable home mortgages, including the Home Owners' Loan Corporation (HOLC) and Federal Housing Administration (FHA). HOLC and FHA directed widespread neighborhood appraisals to determine investment risk, referred to as "redlining," which took into account residents' race. Redlining thereby contributed to segregation, disinvestment, and racial inequities in opportunities for homeownership and wealth accumulation. Recent research examines associations between historical redlining and subsequent environmental determinants of health and health-related outcomes. In this scoping review, we assess the extent of the current body of evidence, the range of outcomes studied, and key study characteristics, examining the direction and strength of the relationship between redlining, neighborhood environments, and health as well as different methodological approaches. Overall, studies nearly universally report evidence of an association between redlining and health-relevant outcomes, although heterogeneity in study design precludes direct comparison of results. We critically consider evidence regarding HOLC's causality and offer a conceptual framework for the relationship between redlining and present-day health. Finally, we point to key directions for future research to improve and broaden understanding of redlining's enduring impact and translate findings into public health and planning practice.

Historical redlining and the epidemiology of present-day firearm violence in the United States: A multi-city analysis

Firearm violence is a major cause of morbidity, mortality, and racial health disparities in the United States. Previous studies have identified associations between historically racist housing discrimination (i.e., redlining practices) and firearm violence; however, these studies generally have been limited to a single city and have yet to provide sufficient evidence through which to determine the extent and dynamics of the impact of this relationship across the country. The aim of our study was (1) to estimate the association of historical redlining on both violent and firearm death across the country in nested models; and (2) to examine spatial non-stationarity to determine whether the impact of historical redlining on violent and firearm death was the same across the U.S. We used multilevel Bayesian conditional autoregressive Poisson models to determine the relationship between redlining as illustrated through Home Owners' Loan Corporation maps and 2019 violent and firearm deaths at the ZIP code-level nested within 21 cities across the U.S. We found that at the ZIP code level, there was a dose-responsive relationship between HOLC grading and the incidence of present-day firearm deaths. In general, redlined ZIP codes had higher relative incidence of firearm deaths. Associations were not stable across cities. For example, associations were relatively stronger in Baltimore, MD and weaker in Los Angeles, CA. This research reinforces the findings of previous studies examining the impact of redlining on firearm death across the extent of the entire country in 21 cities and claim that HOLC grades are associated with present-day violence.

Racial Differences in Positive Airway Pressure Adherence in the Treatment of Sleep Apnea

Although data are limited, studies suggest on average lower positive airway pressure use in Black, indigenous, and people of color (BIPOC) compared with Whites in most but not all studies. Most of these observational studies are certainly limited by confounding by socioeconomic status and other unmeasured factors that likely contribute to differences. The etiology of these observed disparities is likely multifactorial, due in part to financial limitations, differences in sleep opportunity, poor sleep quality due to environmental disruptions, and so forth. These disparities in sleep health are likely related to chronic inequities, including experiences of racism, neighborhood features, structural, and contextual factors. Dedicated studies focusing on understanding adherence in BIPOC are lacking. Further research is needed to understand determinants of PAP use in BIPOC subjects and identify feasible interventions to improve sleep health and reduce sleep apnea treatment disparities.

Environmental Health: A Position Paper From the American College of Physicians

Environmental health refers to the health effects associated with environmental factors, such as air pollution, water contamination, and climate change. Environmental hazards are associated with poor outcomes in common diseases, including diabetes and heart disease. In this position paper, the American College of Physicians (ACP) seeks to inform physicians about environmental health and offers policymakers recommendations to reduce the adverse health consequences of climate change, improve air and water quality, reduce exposure to toxic substances, and address environmental injustice. ACP affirms that all communities, including people of color, people with low income, and marginalized populations, deserve to live in a healthy environment.

The effects of the historical practice of residential redlining in the United States on recent temporal trends of air pollution near New York City schools

BACKGROUND

In the 1930's the United States (US) sponsored Home Owners' Loan Corporation (HOLC) created maps that determined risk for mortgage lending based on the racial and ethnic composition of neighborhoods leading to disinvestment in "redlined" or highest risk neighborhoods. This historical practice has perpetuated racial and economic segregation, and health disparities, that persist today. Interventions near schools where children spend large portions of the day, could impact large groups of children but schools are an often-overlooked environment for exposure. Despite a declining trend of ambient pollution in New York City (NYC) between 1998 and 2012, little is known about differences in air quality improvement near schools by historical redlining neighborhood status. Our objective was to examine if recent temporal trends of air pollution near NYC public schools differed in historically redlined neighborhoods.

METHODS

We examined annual average street-level concentrations of combustion-related air pollutants (black carbon (BC), particulate matter (PM_2.5), nitrogen dioxide (NO₂), and nitric oxide (NO)), within a 250-m radius around schools using NYC Community Air Survey land-use regression models (n = 1,462). Year of monitoring, historical redlining (binary), and summer ozone were included in multivariable linear regression using generalized estimating equation models. Average annual percent change (APC) in pollutant concentration was calculated. Models were further stratified by historical redlining and a multiplicative interaction term (year of monitoring × historical redlining) was used to assess effect modification.

RESULTS

Overall, there was a decreasing trend of BC (APC = -4.40%), PM_2.5 (-3.92%), NO₂ (-2.76%), and NO (-6.20%) during the 10-year period. A smaller reduction of BC, PM_2.5 and NO was observed in redlined neighborhoods (n = 722), compared to others (n = 740): BC (APC: -4.11% vs -4.69%; P_interaction < 0.01), PM_2.5 (-3.82% vs -4.11%; P_interaction < 0.01), and NO (-5.73% vs -6.67%; P_interaction < 0.01). Temporal trends of NO₂ did not differ by historical redlining (P_interaction = 0.60).

CONCLUSIONS

Despite significant reductions in annual average pollution concentrations across NYC, schools in historically redlined neighborhoods, compared to others, experienced smaller decrease in pollution, highlighting a potential ongoing ramification of the discriminatory practice.

Exploring environmenATL justice and data analytics in an environmental studies lab course

The environmental studies laboratory is an exciting place where students investigate, analyze, and reflect. Students test and apply theories and make abstract concepts concrete. As an example, ecology and environmental science are increasingly using "big data" to expand and refine research questions. This commentary reflects on the design and integration of an environmental justice and data analytics module in an environmental studies lab course. The module introduces an environmental justice framework to give students an understanding of tools and strategies to engage, assess, and intervene at multiple levels; while also developing advocacy and communication skills. Poor and minority populations have historically borne the brunt of environmental inequalities in the United States, suffering disproportionally from the effects of pollution, resource depletion, dangerous jobs, limited access to common resources, and exposure to environmental hazards. Paying particular attention to "redlining" and the ways that race, ethnicity, class, and gender have shaped the political and economic dimensions of environmental injustices, this module challenges students to critically examine redlining, socioeconomic, and environmental factors in Atlanta, Georgia (USA) to develop and explore research questions that may visually and/or statistically illuminate trends, patterns, and processes of environmenATL justice. This module also introduces some of the basic data handling and data analysis skills that give students an understanding of data types, descriptive statistics, sampling, and basic inferential statistics. By intentionally incorporating environmental justice activities and conversations in the classroom, instructors afford students an opportunity to engage in authentic examination of their world and make positive changes. Many of the skills learned and knowledge gained in this activity are directly transferable to post-baccalaureate studies (e.g., graduate school, medical school, professional training, etc.) and the world of employment. The module can also be adapted to various curriculum, courses, and communities.

Historical Redlining Impacts Contemporary Environmental and Asthma-related Outcomes in Black Adults

Rationale: Environmental threats and poorly controlled asthma disproportionately burden Black people. Some have attributed this to socioeconomic or biologic factors; however, racism, specifically historical redlining, a U.S. discriminatory mortgage lending practice in existence between the 1930s and the 1970s, may have actuated and then perpetuated poor asthma-related outcomes. Objectives: To link historical redlining (institutional racism) to contemporary environmental quality- and lung health-related racial inequity. Methods: Leveraging a broadly recruited asthma registry, we geocoded 1,034 registry participants from Pittsburgh/Allegheny County, Pennsylvania, to neighborhoods subjected to historical redlining, as defined by a 1930s Home Owners' Loan Corporation (HOLC) map. Individual-level clinical/physiologic data, residential air pollution, demographics, and socioeconomic factors provided detailed characterization. We determined the prevalence of uncontrolled and/or severe asthma and other asthma-related outcomes by HOLC (neighborhood) grade (A-D). We performed a stratified analysis by self-identified race to assess the distribution of environmental and asthma risk within each HOLC grade. Measurements and Main Results: The registry sampling overall reflected Allegheny County neighborhood populations. The emissions of carbon monoxide, filterable particulate matter <2.5 μm, sulfur dioxide, and volatile organic compounds increased across HOLC grades (all P ⩽ 0.004), with grade D neighborhoods encumbered by the highest levels. The persistent, dispersive socioenvironmental burden peripherally extending from grade D neighborhoods, including racialized access to healthy environments (structural racism), supported a long-term impact of historical/HOLC redlining. The worst asthma-related outcomes, including uncontrolled and/or severe asthma (P < 0.001; Z = 3.81), and evidence for delivery of suboptimal asthma care occurred among registry participants from grade D neighborhoods. Furthermore, elevated exposure to filterable particulate matter <2.5 μm, sulfur dioxide, and volatile organic compound emissions (all P < 0.050) and risk of uncontrolled and/or severe asthma (relative risk [95% confidence interval], 2.30 [1.19, 4.43]; P = 0.009) demonstrated inequitable distributions within grade D neighborhood boundaries, disproportionately burdening Black registry participants. Conclusions: The racist practice of historical/HOLC redlining profoundly contributes to long-term environmental and asthma-related inequities in Black adults. Acknowledging the role racism has in these outcomes should empower more specific and novel interventions targeted at reversing these structural issues.

Population-Based Disparities in U.S. Urban Heat Exposure from 2003 to 2018

Previous studies have shown, in the United States (U.S.), that communities of color are exposed to significantly higher temperatures in urban environments than complementary White populations. Studies highlighting this disparity have generally been cross-sectional and are therefore "snapshots" in time. Using surface urban heat island (SUHI) intensity data, U.S. Census 2020 population counts, and a measure of residential segregation, this study performs a comparative analysis between census tracts identified as prevalent for White, Black, Hispanic and Asian populations and their thermal exposure from 2003 to 2018. The analysis concentrates on the top 200 most populous U.S. cities. SUHI intensity is shown to be increasing on average through time for the examined tracts. However, based on raw observations the increase is only statistically significant for White and Black prevalent census tracts. There is a 1.25 K to ~2.00 K higher degree of thermal exposure on average for communities of color relative to White prevalent areas. When examined on an inter-city basis, White and Black prevalent tracts had the largest disparity, as measured by SUHI intensity, in New Orleans, LA, by <6.00 K. Hispanic (>7.00 K) and Asian (<6.75 K) prevalent tracts were greatest in intensity in San Jose, CA. To further explore temporal patterns, two models were developed using a Bayesian hierarchical spatial temporal framework. One models the effect of varying the percentages of each population group relative to SUHI intensity within all examined tracts. Increases in percentages of Black, Hispanic, and Asian populations contributed to statistically significant increases in SUHI intensity. White increases in population percentage witnessed a lowering of SUHI intensity. Throughout all modeled tracts, there is a statistically significant 0.01 K per year average increase in SUHI intensity. A second model tests the effect of residential segregation on thermal inequity across all examined cities. Residential segregation, indeed, has a statistically significant positive association with SUHI intensity based on this portion of the analysis. Similarly, there is a statistically significant 0.01 K increase in average SUHI intensity per year for all cities. Results from this study can be used to guide and prioritize intervention strategies and further urgency related to social, climatic, and environmental justice concerns.

Vulnerable, Resilient, or Both? A Qualitative Study of Adaptation Resources and Behaviors to Heat Waves and Health Outcomes of Low-Income Residents of Urban Heat Islands

Little is known of how low-income residents of urban heat islands engage their knowledge, attitudes, behaviors, and resources to mitigate the health impacts of heat waves. In this qualitative study, we conducted semi-structured interviews with 40 adults in two such neighborhoods in Los Angeles California to explore their adaptation resources and behaviors, the impacts of heat waves on physical and mental health, and threat assessments of future heat waves. Eighty percent of participants received advanced warning of heat waves from television news and social media. The most common resource was air conditioning (AC) units or fans. However, one-third of participants lacked AC, and many of those with AC engaged in limited use due primarily to the high cost of electricity. Adaptation behaviors include staying hydrated, remaining indoors or going to cooler locations, reducing energy usage, and consuming certain foods and drinks. Most of the participants reported some physical or mental health problem or symptom during heat waves, suggesting vulnerability to heat waves. Almost all participants asserted that heat waves were likely to increase in frequency and intensity with adverse health effects for vulnerable populations. Despite limited resources, low-income residents of urban heat islands utilize a wide range of behaviors to minimize the severity of health impacts, suggesting they are both vulnerable and resilient to heat waves.

Extreme temperatures during pregnancy and adverse birth outcomes: Evidence from 2009 to 2018 U.S. national birth data

We provide the first estimates of the impacts of prenatal exposure to extreme temperatures on infant health at birth using the latest national birth data from 2009 to 2018 from all U.S. states. We consistently find that an additional day with mean temperature greater than 80°F or less than 10°F increases preterm births and low birthweight. Strikingly, the adverse effects are borne disproportionately by Black and Hispanic mothers, suggesting that the projected increase in extreme temperatures may further exacerbate the existing birth health disparities across different race/ethnicity groups. We also contribute by investigating the impact of deviations from the normal weather pattern, to identify the extreme weather events after accounting for the adaptation response. We find that prenatal exposure to extreme heat two standard deviations above county's historic average induces preterm births and NICU admissions, particularly for mothers whose pregnancies overlap with summer months. These results are timely and policy relevant, considering the recent weather trends with rising temperatures and frequent extreme weather events.

Inequality in the availability of residential air conditioning across 115 US metropolitan areas

Continued climate change is increasing the frequency, severity, and duration of populations' high temperature exposures. Indoor cooling is a key adaptation, especially in urban areas, where heat extremes are intensified-the urban heat island effect (UHI)-making residential air conditioning (AC) availability critical to protecting human health. In the United States, the differences in residential AC prevalence from one metropolitan area to another is well understood, but its intra-urban variation is poorly characterized, obscuring neighborhood-scale variability in populations' heat vulnerability and adaptive capacity. We address this gap by constructing empirically derived probabilities of residential AC for 45,995 census tracts across 115 metropolitan areas. Within cities, AC is unequally distributed, with census tracts in the urban "core" exhibiting systematically lower prevalence than their suburban counterparts. Moreover, this disparity correlates strongly with multiple indicators of social vulnerability and summer daytime surface UHI intensity, highlighting the challenges that vulnerable urban populations face in adapting to climate-change driven heat stress amplification.

Redlining, racism and food access in US urban cores

In the 1930s, the Home Owners' Loan Corporation (HOLC) graded the mortgage security of urban US neighborhoods. In doing so, the HOLC engaged in the practice, imbued with racism and xenophobia, of "redlining" neighborhoods deemed "hazardous" for lenders. Redlining has caused persistent social, political and economic problems for communities of color. Linkages between redlining and contemporary food access remain unexamined, even though food access is essential to well-being. To investigate this, we used a census tract-level measure of low-income and low grocery store food access from the US Department of Agriculture Food Access Research Atlas, redlining data from Mapping Inequality Project, and demographic data from the American Community Survey. We employed generalized estimating equations with robust covariance estimates to analyze data pertaining to 10,459 census tracts in 202 US cities. Tracts that the HOLC graded as "C" ("decline in desirability") and "D" ("hazardous") had reduced contemporary food access compared to those graded "A" ("best"). Increases in contemporary census tract proportions of Black, Hispanic, or other racial/ethnic minority residents, as well as disabled residents, were associated with reduced food access. Increases in contemporary proportions of residents age 75 years and older or those without a car were associated with better food access. Tracts that underwent housing redevelopment since being graded had better food access, while those undergoing gentrification had reduced food access. Results suggest that issues of redlining, housing discrimination, racism, ableism, displacement, and food inaccessibility are deeply intertwined.

Historical Urban Tree Canopy Cover Change in Two Post-Industrial Cities

Present-day spatial patterns of urban tree canopy (UTC) are created by complex interactions between various human and biophysical drivers; thus, urban forests represent legacies of past processes. Understanding these legacies can inform municipal tree planting and canopy cover goals while also addressing urban sustainability and inequity. We examined historical UTC cover patterns and the processes that formed them in the cities of Chelsea and Holyoke, Massachusetts using a mixed methods approach. Combining assessments of delineated UTC from aerial photos with historical archival data, we show how biophysical factors and cycles of governance and urban development and decay have influenced the spatiotemporal dynamics of UTC. The spatially explicit UTC layers generated from this research track historical geographic tree distribution and dynamic change over a 62-year period (1952-2014). An inverse relationship was found between UTC and economic prosperity: while canopy gains occurred in depressed economic periods, canopy losses occurred in strong economic periods. A sustainable increase of UTC is needed to offset ongoing losses and overcome historical legacies that have suppressed UTC across decades. These findings will inform future research on residential canopy formation and stability, but most importantly, they reveal how historical drivers can be used to inform multi-decadal UTC assessments and the creation of targeted, feasible UTC goals at neighborhood and city scales. Such analyses can help urban natural resource managers to better understand how to protect and expand their cities' UTC over time for the benefit of all who live in and among the shade of urban forests.

Heat exposure misclassification: Do current methods of classifying diurnal range in individually experienced temperatures and heat indices accurately reflect personal exposure?

Wearable sensors have been used to collect information on individual exposure to excessive heat and humidity. To date, no consistent diurnal classification method has been established, potentially resulting in missed opportunities to understand personal diurnal patterns in heat exposure. Using individually experienced temperatures (IET) and heat indices (IEHI) collected in the southeastern United States, this work aims to determine whether current methods of classifying IETs and IEHIs accurately characterize "day," which is typically the warmest conditions, and "night," which is typically the coolest conditions. IET and IEHI data from four locations were compared with the closest hourly weather station. Different day/night classifications were compared to determine efficacy. Results indicate that diurnal IET and IEHI ranges are higher than fixed-site ranges. Maximum IETs and IEHIs are warmer and occur later in the day than ambient conditions. Minimum IETs are lower and occur earlier in the day than at weather stations, which conflicts with previous assumptions that minimum temperatures occur at night. When compared to commonly used classification methods, a method of classifying day and night based on sunrise and sunset times best captured the occurrence of maximum IETs and IEHIs. Maximum IETs and IEHIs are often identified later in the evening, while minimum IETs and IEHIs occur throughout the day. These findings support future research focusing on nighttime heat exposure, which can exacerbate heat-related health issues, and diurnal patterns of personal exposure throughout the entire day as individual patterns do not necessarily follow the diurnal pattern seen in ambient conditions.

Ecohealth Villages: A Framework for an Ecosystem Approach to Health in Human Settlements

As life emerged on Earth, it began to affect its environments. It still does. The complex interactions between living things and their environments mediate the character of both. Today, this is apparent in the global impacts humans have made on ecosystems, with resultant reciprocal impacts on human health. This paper is concerned with that reciprocity, which may be considered as a link between ecosystems and human populations. We will distinguish an ecosystem approach to human health—or ecohealth—from One Health and planetary health perspectives. We will also propose a conceptual framework that can be used to distinguish human settlements as Ecohealth Villages. Broadly defined, an Ecohealth Village is a settlement that recognizes the interactions between healthy ecosystems and the health of people who live, work, learn, and play in it. The key principles of an Ecohealth Villages are as follows: community ownership, ecological restoration, sustainability, social and gender equity, integrated perspectives, and traditional practices and knowledge. Together, they support a holistic, ecosystem approach to health in human settlements, as demonstrated in case studies from Mexico and Aotearoa New Zealand.

Informing Nature-based Climate Solutions for the United States with the best-available science

Nature-based Climate Solutions (NbCS) are managed alterations to ecosystems designed to increase carbon sequestration or reduce greenhouse gas emissions. While they have growing public and private support, the realizable benefits and unintended consequences of NbCS are not well understood. At regional scales where policy decisions are often made, NbCS benefits are estimated from soil and tree survey data that can miss important carbon sources and sinks within an ecosystem, and do not reveal the biophysical impacts of NbCS for local water and energy cycles. The only direct observations of ecosystem-scale carbon fluxes, for example, by eddy covariance flux towers, have not yet been systematically assessed for what they can tell us about NbCS potentials, and state-of-the-art remote sensing products and land-surface models are not yet being widely used to inform NbCS policymaking or implementation. As a result, there is a critical mismatch between the point- and tree-scale data most often used to assess NbCS benefits and impacts, the ecosystem and landscape scales where NbCS projects are implemented, and the regional to continental scales most relevant to policymaking. Here, we propose a research agenda to confront these gaps using data and tools that have long been used to understand the mechanisms driving ecosystem carbon and energy cycling, but have not yet been widely applied to NbCS. We outline steps for creating robust NbCS assessments at both local to regional scales that are informed by ecosystem-scale observations, and which consider concurrent biophysical impacts, future climate feedbacks, and the need for equitable and inclusive NbCS implementation strategies. We contend that these research goals can largely be accomplished by shifting the scales at which pre-existing tools are applied and blended together, although we also highlight some opportunities for more radical shifts in approach.

Lifestyle Medicine Interventions for Personal and Planetary Health: The Urgent Need for Action

The deterioration of planetary health—from threats such as climate change, environmental pollution, biodiversity loss, and ocean acidification—are a growing hazard to the foundation of health and the “healthspan.” For those with chronic conditions—a large and growing subset of the global population—the health dangers are even greater. Climate change is a threat to the very pillars of lifestyle medicine that we rely on to prevent and manage chronic disease. Already, the planetary crisis is limiting our ability to prescribe healthy nutrition, safe outdoor physical activity, stress management strategies, social connection, restorative sleep, and toxic substance avoidance. In this article, we discuss the proceedings of our workshop at the American College of Lifestyle Medicine (ACLM) annual conference LM2021, “Lifestyle Medicine for Personal and Planetary Health.” We examine how lifestyle medicine (LM) interventions are a prescription for individual, community, and planetary health. Our prescriptions work to not only restore the health of individuals and families, but also to bolster health equity while allowing us to mitigate and adapt to the health impacts of the planetary crises.

Historical redlining and food environments: A study of 102 urban areas in the United States

OBJECTIVE

Unhealthy food environments are disproportionally concentrated in neighborhoods with clustering of racial/ethnic minorities and poverty. This disparity has been blamed, in part, on market self-regulation. This explanation risks overlooking past and current practices of racial segregation that have created and reinforced the obstacles blocking investments from food retailers in marginalized neighborhoods. We fill this gap by investigating how the long-term ramifications of redlining, discriminatory housing practices enacted by federal Home Owner Lending Corporation (HOLC) in the 1930s, has evolved generations later to disproportionally exposing neighborhoods to unhealthy food environments.

METHODS

We overlaid historical redlining maps over 2010 food environment observations at the census tract level to identify areas with less healthy food environments and to assess the historical context of those areas. For 11,651 census tracts within 102 U.S. urban areas, we described the healthiness of food environments as measured by the modified retail food environment index (mRFEI). Using hurdle models with random effects, we further examined the association between redlining housing practice and food environments.

RESULTS

The results indicate that historically redlined neighborhoods show a higher likelihood for unhealthy retail food environments even for census tracts with present-day economic and racial privilege.

CONCLUSION

The current evidence shows how structural discrimination manifested by unjust housing practices and racial residential segregation fueled an uneven food environment where minority neighborhoods disproportionally bore the brunt of restrictive food access. It highlights an urgent need to ameliorate patterns of housing inequality as a fix to unequal food environments.

Impact of Federal, State, and Local Housing Policies on Disparities in Cardiovascular Disease in Black/African American Men and Women: From Policy to Pathways to Biology

Racist and discriminatory federal, state, and local housing policies significantly contribute to disparities in cardiovascular disease incidence and mortality for individuals that self-identify as Black or African American. Here we highlight three key housing policies - "redlining," zoning, and the construction of highways - which have wrought a powerful, sustained, and destructive impact on cardiovascular health in Black/African American communities. Redlining and highway construction policies have restricted access to quality health care, increased exposure to carcinogens such as PM2.5, and increased exposure to extreme heat. At the root of these policy decisions are longstanding, toxic societal factors including racism, segregation, and discrimination, which also serve to perpetuate racial inequities in cardiovascular health. Here, we review these societal and structural factors and then link them with biological processes such as telomere shortening, allostatic load, oxidative stress, and tissue inflammation. Lastly, we focus on the impact of inflammation on the immune system and the molecular mechanisms by which the inflamed immune microenvironment promotes the formation of atherosclerotic plaques. We propose that racial residential segregation and discrimination increases tissue inflammation and cytokine production, resulting in dysregulated immune signaling, which promotes plaque formation and cardiovascular disease. This framework has the power to link structural racism not only to cardiovascular disease, but also to cancer.

The Curious Relationship Between COVID-19 Lockdowns and Urban Heat Islands

The COVID-19 pandemic has been a life-altering shock to society. However, there have been serendipitous outcomes from the associated lockdowns ranging from improved air quality to reductions in carbon emissions. Liu et al. (2022, https://doi.org/10.1029/2021GL096842) revealed that even the magnitude of the heat islands in Chinese cities were reduced due to a decline in human activities and their associated anthropogenic contributions. These surprising findings have significant implications for understanding intersections among climate, health, energy, urban planning, transportation, and infrastructure.

Historical Redlining Is Associated with Present-Day Air Pollution Disparities in U.S. Cities

Communities of color in the United States are systematically exposed to higher levels of air pollution. We explore here how redlining, a discriminatory mortgage appraisal practice from the 1930s by the federal Home Owners' Loan Corporation (HOLC), relates to present-day intraurban air pollution disparities in 202 U.S. cities. In each city, we integrated three sources of data: (1) detailed HOLC security maps of investment risk grades [A ("best"), B, C, and D ("hazardous", i.e., redlined)], (2) year-2010 estimates of NO₂ and PM_2.5 air pollution levels, and (3) demographic information from the 2010 U.S. census. We find that pollution levels have a consistent and nearly monotonic association with HOLC grade, with especially pronounced (>50%) increments in NO₂ levels between the most (grade A) and least (grade D) preferentially graded neighborhoods. On a national basis, intraurban disparities for NO₂ and PM_2.5 are substantially larger by historical HOLC grade than they are by race and ethnicity. However, within each HOLC grade, racial and ethnic air pollution exposure disparities persist, indicating that redlining was only one of the many racially discriminatory policies that impacted communities. Our findings illustrate how redlining, a nearly 80-year-old racially discriminatory policy, continues to shape systemic environmental exposure disparities in the United States.

Historical Redlining Is Associated with Present-Day Air Pollution Disparities in U.S. Cities

Communities of color in the United States are systematically exposed to higher levels of air pollution. We explore here how redlining, a discriminatory mortgage appraisal practice from the 1930s by the federal Home Owners' Loan Corporation (HOLC), relates to present-day intraurban air pollution disparities in 202 U.S. cities. In each city, we integrated three sources of data: (1) detailed HOLC security maps of investment risk grades [A ("best"), B, C, and D ("hazardous", i.e., redlined)], (2) year-2010 estimates of NO₂ and PM_2.5 air pollution levels, and (3) demographic information from the 2010 U.S. census. We find that pollution levels have a consistent and nearly monotonic association with HOLC grade, with especially pronounced (>50%) increments in NO₂ levels between the most (grade A) and least (grade D) preferentially graded neighborhoods. On a national basis, intraurban disparities for NO₂ and PM_2.5 are substantially larger by historical HOLC grade than they are by race and ethnicity. However, within each HOLC grade, racial and ethnic air pollution exposure disparities persist, indicating that redlining was only one of the many racially discriminatory policies that impacted communities. Our findings illustrate how redlining, a nearly 80-year-old racially discriminatory policy, continues to shape systemic environmental exposure disparities in the United States.

The impact of social determinants of health on the overall wellbeing of children: A review for the pediatric surgeon

Disparities in health care access, quality, and outcomes for pediatric patients, and their relationship to race and socioeconomic status (SES) have been extensively documented. The underlying causes behind such disparities have been less carefully studied, as clinicians and researchers often fail to look past immutable features such as race, into modifiable factors like social determinants of health (SDOH). A child's environment affects their patterns of social engagement, sense of security, and overall well-being. Resources such as affordable housing, access to education, public safety, and availability of healthy foods and safe play spaces impact and enhance quality of life, and have significant influence on both health and health care outcomes. These upstream indicators are often unrecognized or misidentified as health concerns. Few pediatric surgery publications discuss SDOH and their effects on children. This paper aims to introduce the five domains of SDOH (economic stability, education, social and community context, health and healthcare, and neighborhood and built environment) along with strategies to identify and address needs in these domains from a provider, hospital, and health system's perspective. It is anticipated that this information will serve as a foundation for pediatric surgeons to understand and develop processes that ameliorate disparities related to SDOH and improve surgical outcomes and the well-being of all children.

Climate Change, Environmental Disasters, and Health Inequities: The Underlying Role of Structural Inequalities

PURPOSE OF REVIEW

We review and analyze recent literature in public health, urban planning, and disaster management to better understand the relationships between climate change, natural disasters, and root causes of health disparities in the USA.

RECENT FINDINGS

Existing scholarship establishes clear linkages between climate change and increasing occurrences and severity of natural disasters across the USA. The frequency and types of disasters vary by region and impact both short and long-term health outcomes. Current research highlights health inequities affecting lower income and minoritized communities disproportionately, but data-driven studies critically examining the role of structural inequalities in climate-induced health disparities are sparse. Adding to the body of knowledge, our conceptual framework maps how long-standing structural inequalities in policy, practice, and funding shape vulnerability of lower-income, racially and ethnically marginalized individuals. Vulnerability follows three common pathways: disparities in "exposure", "sensitivity", and "resiliency" before, during, and after a climate disaster. We recommend that future research, policy, and practice shift towards solutions that unearth and address the structural biases that cause environmental disaster and health inequities.

High-Resolution Estimation of Monthly Air Temperature from Joint Modeling of In Situ Measurements and Gridded Temperature Data

Surface air temperature is an important variable in quantifying extreme heat, but high-resolution temporal and spatial measurement is limited by sparse climate-data stations. As a result, hyperlocal models of extreme heat involve intensive physical data collection efforts or analyze satellite-derived land-surface temperature instead. We developed a geostatistical model that integrates in situ climate-quality temperature records, gridded temperature data, land-surface temperature estimates, and spatially consistent covariates to predict monthly averaged daily maximum surface-air temperatures at spatial resolutions up to 30 m. We trained and validated the model using data from North Carolina. The fitted model showed strong predictive performance with a mean absolute error of 1.61 ∘F across all summer months and a correlation coefficient of 0.75 against an independent hyperlocal temperature model for the city of Durham. We show that the proposed model framework is highly scalable and capable of producing realistic temperature fields across a variety of physiographic settings, even in areas where no climate-quality data stations are available.

Targeted implementation of cool roofs for equitable urban adaptation to extreme heat

Cities are facing the twin pressures of greenhouse gas driven climatic warming and locally induced urban heating. These pressures are threatening populations that are sensitive to extreme heat due to sociodemographic factors including economic means. Heat-reducing infrastructure adaptation measures such as reflective "cool" materials can reduce urban temperatures. Here we examine the needs-based equity implications associated with heat-reducing cool roofing in Maricopa County, Arizona through application of high-resolution urban-atmospheric simulations. We simulate heatwave conditions and evaluate the air temperature reduction arising from uniform cool roof implementation (i.e., the entire urbanized county), and contrast results against simulated cooling impacts of needs-based targeted cool roof implementation in sociodemographically heat sensitive areas. We find that installing cool roofs uniformly, rather than in a targeted fashion, provides on average 0.66 °C reduction in the highest heat sensitivity area and 0.39 °C temperature reduction in the lowest heat sensitivity area due in part to a higher roof area density in the heat sensitive area. Targeting cool roof implementation yields 0.45 °C cooling in the most sensitive areas compared to 0.22 °C cooling in the least sensitive areas, meaning that needs-based targeted cool roofs in high sensitivity areas provide more relief than cool roofs targeted at low sensitivity areas, thus providing more cooling where it is most needed. Needs-based targeted implementation has the dual benefits of concurrently producing more than twice as much cooling and reducing heat exposure for the largest absolute number of individuals in the densely populated, highly heat sensitive areas. Targeting cool roof implementation to high heat sensitivity areas, however, does not achieve thermally equal temperatures in Maricopa County because the high sensitivity areas were substantially warmer than low sensitivity areas prior to implementation. This study illustrates the utility of a new "Targeted Urban Heat Adaptation" (TUHA) framework to assess needs-based equity implications of heat-reducing strategies and underscores its importance by examining the impacts of cooling interventions across sociodemographically heterogeneous urban environments.

Modeling the Relationships Between Historical Redlining, Urban Heat, and Heat-Related Emergency Department Visits: An Examination of 11 Texas Cities

Place-based structural inequalities can have critical implications for the health of vulnerable populations. Historical urban policies, such as redlining, have contributed to current inequalities in exposure to intra-urban heat. However, it is unknown whether these spatial inequalities are associated with disparities in heat-related health outcomes. The aim of this study is to determine the relationships between historical redlining, intra-urban heat conditions, and heat-related emergency department visits using data from eleven Texas cities. At the zip code level, the proportion of historical redlining was determined, and heat exposure was measured using daytime and nighttime land surface temperature (LST). Heat-related inpatient and outpatient rates were calculated based on emergency department visit data that included ten categories of heat-related diseases between 2016 and 2019. Regression or spatial error/lag models revealed significant associations between higher proportions of redlined areas in the neighborhood and higher LST (Coef. = 0.0122, 95% CI = 0.0039 - 0.0205). After adjusting for indicators of social vulnerability, neighborhoods with higher proportions of redlining showed significantly elevated heat-related outpatient visit rate (Coef. = 0.0036, 95% CI = 0.0007-0.0066) and inpatient admission rate (Coef. = 0.0018, 95% CI = 0.0001-0.0035). These results highlight the role of historical discriminatory policies on the disparities of heat-related illness and suggest a need for equity-based urban heat planning and management strategies.

Climate Change and Medical Education: An Integrative Model

Medical schools face a challenge when trying to include new topics, such as climate change and health (CCH), in their curricula because of competing demands from more traditional biomedical content. At the same time, an understanding of CCH topics is crucial for physicians as they have clear implications for clinical practice and health care delivery. Although some medical schools have begun to incorporate CCH into curricula, the inclusion usually lacks a comprehensive framework for content and implementation. The authors propose a model for integrating CCH into medical school curricula using a practical, multistakeholder approach designed to mitigate competition for time with existing content by weaving meaningful CCH examples into current curricular activities. After the authors identified stakeholders to include in their curricular development working group, this working group determined the goals and desired outcomes of the curriculum; aligned those outcomes with the school's framework of educational objectives, competencies, and milestones; and strove to integrate CCH goals into as many existing curricular settings as possible. This article includes an illustration of the proposed model for one of the curricular goals (understanding the impacts of climate change on communities), with examples from the CCH curriculum integration that began in the fall of 2020 at the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University. The authors have found that this approach does minimize competition for time with existing content and allows mapping of content to existing curricular competencies and milestones, while encouraging a broad understanding of CCH in the context of individual patients, populations, and communities. This model for curricular integration can be applied to other topics such as social determinants of health, health equity, disability studies, and structural racism.

Associations Between Historical Redlining and Present-Day Heat Vulnerability Housing and Land Cover Characteristics in Philadelphia, PA

Historical, institutional racism within the housing market may have impacted present-day disparities in heat vulnerability. We quantified associations between historically redlined areas with present-day property and housing characteristics that may enhance heat vulnerability in Philadelphia, PA. We used color-coded Home Owners Loan Corporation (HOLC) maps and tax assessment data to randomly select 100 present-day (2018-2019) residential properties in each HOLC grade area (A = Best; B, C, and D = Most hazardous; N = 400 total). We conducted virtual inventories of the properties using aerial and streetview imagery for land cover and housing characteristics (dark roof color, flat roof shape, low or no mature tree canopy, no recently planted street trees) that may enhance heat vulnerability. We used modified Poisson regression models to estimate associations of HOLC grades with the property characteristics, unadjusted and adjusted for historical and contemporary measures of the neighborhood sociodemographic environment. Compared to grade A areas, higher proportions of properties in grade B, C, and D areas had dark roofs, low/no mature tree canopy, and no street trees. Adjusting for historical sociodemographics attenuated associations, with only associations with low or no tree canopy remaining elevated. Adjusting for present-day concentrated racial and socioeconomic deprivation did not substantially impact overall findings. In Philadelphia, PA, HOLC maps serve as spatial representations of present-day housing and land cover heat vulnerability characteristics. Further analyses incorporating longitudinal data on urban redevelopment, reinvestment, and neighborhood change are needed to more fully represent complex relationships among historical racism, residential segregation, and heat vulnerability.

Urbanization Impact on Regional Climate and Extreme Weather: Current Understanding, Uncertainties, and Future Research Directions

Urban environments lie at the confluence of social, cultural, and economic activities and have unique biophysical characteristics due to continued infrastructure development that generally replaces natural landscapes with built-up structures. The vast majority of studies on urban perturbation of local weather and climate have been centered on the urban heat island (UHI) effect, referring to the higher temperature in cities compared to their natural surroundings. Besides the UHI effect and heat waves, urbanization also impacts atmospheric moisture, wind, boundary layer structure, cloud formation, dispersion of air pollutants, precipitation, and storms. In this review article, we first introduce the datasets and methods used in studying urban areas and their impacts through both observation and modeling and then summarize the scientific insights on the impact of urbanization on various aspects of regional climate and extreme weather based on more than 500 studies. We also highlight the major research gaps and challenges in our understanding of the impacts of urbanization and provide our perspective and recommendations for future research priorities and directions.

Association of historic redlining and present-day health in Baltimore

BACKGROUND

In the 1930s, the Home Owners' Loan Corporation categorized neighborhoods by investment grade along racially discriminatory lines, a process known as redlining. Although other authors have found associations between Home Owners' Loan Corporation categories and current impacts on racial segregation, analysis of current health impacts rarely use these maps.

OBJECTIVE

To study whether historical redlining in Baltimore is associated with health impacts today.

APPROACH

Fifty-four present-day planning board-defined community statistical areas are assigned historical Home Owners' Loan Corporation categories by area predominance. Categories are red ("hazardous"), yellow ("definitely declining") with blue/green ("still desirable"/"best") as the reference category. Community statistical area life expectancy is regressed against Home Owners' Loan Corporation category, controlling for median household income and proportion of African American residents.

CONCLUSION

Red categorization is associated with 4.01 year reduction (95% CI: 1.47, 6.55) and yellow categorization is associated with 5.36 year reduction (95% CI: 3.02, 7.69) in community statistical area life expectancy at baseline. When controlling for median household income and proportion of African American residents, red is associated with 5.23 year reduction (95% CI: 3.49, 6.98) and yellow with 4.93 year reduction (95% CI: 3.22, 6.23). Results add support that historical redlining is associated with health today.