An Overview of Our Environmental Justice Indicators

Introduction

Communities across the United States are experiencing the worsening effects of climate change: record high temperatures, severe droughts, and increasingly frequent massive hurricanes, floods, and fires. While climate change is a crisis that threatens everyone, not all communities experience the consequences of climate change equally. Many low income neighborhoods and communities of color – who often live near polluting facilities, in floodplains, and/or in areas with substandard housing – are more susceptible to environmentally unfriendly practices, whether everyday risks like air and water pollution, or major climate disasters. 

Addressing these structural issues requires an environmental justice approach: improving environmental conditions, sustainable energy, and public health for everyone, while also recognizing how many historically marginalized communities experience greater harms from pollution, outdated infrastructure, and climate crises. A data-driven approach is essential to understand which communities across the US face these heightened risks.

We are excited to announce four new environmental justice indicators on the National Equity Atlas, which can support public officials, advocates, researchers, and residents concerned with these critical issues around climate change and community wellbeing. Including our existing Air Pollution Indicator, the National Equity Atlas now has five indicators dedicated to critical issues around climate change and environmental justice:

  • Air Pollution: Measuring the relative level of exposure to cancer-causing airborne pollutants for residents in a specific geographic area (city, county, region, state, the entire US)
  • Lead Exposure: Measuring the share of residents in a specific area who live in homes with deteriorated lead-based paint
  • Toxic Flood Risk: Measuring the share of residents in a specific area who live in census tracts with industrial facilities that could spread contaminants in the event of a flood
  • Urban Heating: Measuring the share of residents in a specific area who live in neighborhoods where the built environment leads to an additional rise in temperature
  • Urban Tree Canopy: Measuring the average percentage of land covered by trees for urban residents in a specific area

Here, we show how these indicators can highlight regions across the United States where these five issues are especially prevalent. We also offer key considerations for people interested in working with these data tools. 

Each of the individual Indicator pages contains additional context, key data trends, and strategies for addressing each issue. For more detailed information about data sources and methodology, please visit the Data and Methods section of our website.

Climate resilience and environmental justice are essential projects. Despite recent growth in clean energy production and large-scale public funding for climate-friendly infrastructure, the United States—and world—remain behind the pace needed to prevent a catastrophic rise in the global temperature over the coming generations. We hope these interactive data tools are used to strengthen the work of advocates, researchers, policymakers, community leaders, and concerned residents across the country who are committed to a shared solution.

What parts of the United States stand out in the data?

In a large, ecologically diverse country like the United States, the factors causing climate change and the impacts of climate change – from fires and floods to hurricanes and heating – vary between places. Indicator data like ours is important to highlight the different geographic areas and the communities where these structural issues are of the most concern. The maps below show Indicator data for the 100 largest US metropolitan areas (listed on the Indicator pages as “Regions”).

Put together, the maps show that there is no part of the United States that is spared from climate change and/or the consequences of infrastructure that is not climate resilient. Even cities that have historically avoided large climate disasters are feeling the intensifying impacts of climate change. By no means are these five indicators comprehensive when it comes to environmental justice data, but these data points should stress how critical addressing the climate crisis is for our collective future.

Nationwide, 39 percent of residents in urban areas live in neighborhoods where the built environment (buildings and structures, streets, lots, parks, etc.) raises local temperatures by at least eight degrees Fahrenheit. In multiple parts of the country, the share of residents facing urban heat issues far exceeds 39 percent. Texas and Florida stand out the most: these states are home to seven of the ten metro areas with the highest levels of urban heating. Other hotspots include New Orleans (69 percent), Detroit (60 percent), and California (nine of the 11 metro areas included are above the national average).

By contrast, many of the metros with the lowest levels of urban heating are located in Utah and the Northeast, especially Massachusetts, Connecticut, and Western Pennsylvania.

On average, urban residents in the United States live in neighborhoods with a tree canopy coverage of 18 percent. There is a distinct geographic trend for this indicator, as metro areas in the Midwest, Southeast, and Northeast are generally more likely to have tree canopy coverage compared to metro areas in the Great Plains, Rockies, Southwest, and West Coast. Only one of the 25 metros with the lowest tree canopy coverage lies east of the Mississippi River: Miami, at 9 percent coverage. The two outliers on the West Coast are in the forested Pacific Northwest: the Seattle (28 percent coverage) and Portland, Oregon metro areas (26 percent).

Much of this trend is due to ecology: many of the lowest-ranking metros are located in desert, plains, mountain, and chaparral regions with less natural tree coverage. However, this data also reflects histories of land use policy, development, and urban planning: in recent decades desert areas like Las Vegas, Phoenix, and California’s Inland Empire have surged in population amidst cheaper land and housing costs. However, the relative absence of tree coverage in these areas threatens to exacerbate the worsening effects of global warming in the years to come.

Nationwide, 18 percent of residents live in homes where they are exposed to lead-based paint. However, lead paint risk is more prevalent for residents of metro areas in the Northeast and Upper Midwest. Among the 25 large US metros with highest levels of lead paint exposure, only one is not located in a Midwestern or Northeastern state: San Francisco, where 27 percent of residents risk lead paint exposure at home. By contrast, many of the metros with the lowest levels of lead exposure lie along the Sun Belt, in states like Arizona, Texas, and Florida.

Within this trend is a history of United States home construction: cities with older housing stock face higher levels of risk from lead paint. Many cities in the Northeast and Rust Belt have been densely settled for centuries, and San Francisco was the most prominent West Coast city in the country until the mid-20th century. In many parts of the Sun Belt, a significant share of housing was built after the federal ban on lead paint in 1978. 

As climate change worsens, more Americans are exposed to flooding at a more rapid rate. Nationwide, 25 percent of residents live in neighborhoods nearby toxic industrial and waste sites, and face additional risks of floodwater contamination from these facilities. This is especially concerning for residents in many Northeastern and Midwestern metros, where a larger share of residents face toxic flood risk. All of the ten metros where at least half of residents live near toxic sites at risk of flooding are located in New England, the Rust Belt, or the Gulf Coast (Houston, at 60 percent of residents; and New Orleans, at 50 percent).

Interestingly, the Northeastern metros with high levels of toxic flood risk – places like Boston, Pittsburgh, and New Haven, Connecticut – are also some of the metros with the lowest levels of urban heating and the highest levels of tree canopy coverage. It is important for cities, regions, and states to account for the many different threats from the climate crisis, as there is no one-size-fits-all approach to climate resilience in a nation as large as the United States.

The nationwide Air Pollution Exposure Index is 52, meaning the average American lives in a neighborhood where the cancer risk from air pollution is worse than 52 percent of all Census tracts in the United States. The index is lowest for metros in the Rocky Mountains, the Northeast and Rust Belt, the Florida coastline, and the island of Oahu. By contrast, metros with the worst air pollution are mostly clustered in the Southeast, Lower Midwest, and West Coast, especially California’s Central Valley.

Key considerations for using this data

 

The impacts of pollution, climate change, and climate disasters are uneven across neighborhoods. Environmental justice advocates understand that the people who suffer the most from the effects of climate change are rarely the same people who economically benefit from the activities and industries that worsen it. Working class residents and communities of color often face greater risks from air and water pollution, exposure to toxic materials, disasters like floods and fires, and rising global temperatures.

The new Atlas indicator data can be used to highlight the disparate impacts of environmental challenges for different communities, and to identify communities where green infrastructure and climate resilience should be high priorities. Each indicator includes disaggregated population data by race, age, income, and other demographic differences to show how different communities in the same area can experience these challenges differently.

 

These five indicators represent environmental justice issues that are deeply interconnected. We can put these data points together to illustrate broader structural disparities and environmental justice concerns. In many regions and cities, it is likely that marginalized communities face greater risks in more than one of these issue areas.

 

Air Pollution

Lead Exposure

Toxic Flood Risk

Urban Heating

Urban Tree Canopy

Biodiverse neighborhoods

All residents live in communities with ample greenspace.
X
 
 
X
X

Clean natural resources

All residents enjoy clean air and safe drinking water.
X
X
X
 
X

Climate-friendly infrastructure

All communities have built environments that reduce climate change and protect against the risk of climate disasters.
X
X
X
X
X

Green energy
All communities have access to energy sources besides fossil fuels.
X
 
X
 
 


These five Indicators are not all-encompassing, but are also related to a host of other environmental justice challenges. For example:

  • Lead exposure risk occurs not just through lead-based paint, but the contamination of drinking water from the deterioration of lead-based pipes.
  • Cases like the yearslong lead water crisis in Flint, Michigan also demonstrate that toxic flood waters are just one type of water pollution threatening people across the country. Water contamination from industrial activity or inequitable infrastructure is a daily issue for many Americans.
  • While tree coverage offers many benefits, not all kinds of trees offer the same benefits for local biodiversity, fire prevention, or the preservation of indigenous species. Native trees offer many environmental benefits that nonnative trees do not.

It will be necessary to place our Indicator data in conversation with other research and insights on climate change and environmental justice.

 

Just as these issues are related, so are the solutions. Some of the strategies we can use to address one of these issues will also help improve conditions for other indicators as well. For instance:

As such, public officials, communities, and businesses concerned with one of these issues can find common cause with people working on different, but related, concerns around environmental justice and climate resilience.