On this International Day of Clean Air for Blue Skies, we recognize the tremendous strides the United States has taken towards cleaner air since 1970 under the federal Clean Air Act. And yet the work to achieve this year’s theme of “Healthy Air, Healthy Planet” is not over. There is room for more improvement, particularly to ensure that all communities consistently enjoy the benefits of clean air, including low-income and minority communities disproportionately burdened by air pollution and its sources. Sound policy guided by science has been critical to making progress, and we welcome the U.S. Environmental Protection Agency’s renewed commitment to follow the scientific evidence, which demands additional protections for public health and the environment. For example, public health science strongly supports strengthening the U.S. national ambient standards for fine particulate matter and ozone. U.S. EPA is today presented with an opportunity to update the standards, which are the backbone of the federal Clean Air Act.
The federal-state partnership under the Clean Air Act’s programs aimed at meeting the ambient standards has resulted in improved air quality over the years due to reductions in harmful emissions from polluting industries and mobile sources, even as the U.S. economy and population have grown. According to EPA, combined emissions of six key pollutants dropped by 78 percent between 1970 and 2020, with national average ozone concentrations falling by 25 percent between 1990 to 2020, and annual average fine particulate matter concentrations declining by 41 percent between 2000 and 2020. Power plant emissions of air toxics like mercury also fell by an estimated 96% between 2010 and 2017. Furthermore, the number of unhealthy air days in 35 major U.S. cities based on EPA’s Air Quality Index have fallen from over 2,000 per year as recently as 2002 to less than 1,000 per year from 2013-2020. However, the science shows that more work remains to be done in areas with some of the biggest emitters to alleviate disproportionate burdens on low-income communities and communities of color, to ensure protection for those who are most vulnerable (especially children, the elderly, and people with respiratory conditions), and to prepare for looming threats to air quality in the future.
At the same time that it is focusing on the emissions that directly damage public health, EPA must also account for the current and future threat climate change poses to air quality. A recent EPA report called Climate Change and Social Vulnerability in the United States: A Focus on Six Impacts, looked at the nexus between vulnerable populations, air quality, and climate change. The report highlights the relationship between climate change and air quality, as changes in climate also affect concentrations of fine particulate matter and ozone. As the climate warms, ground-level ozone is more likely to form and reach unhealthy levels on hot sunny days, which now begin earlier in the spring and last longer into the fall, resulting in prolonged exposures. Climate change also creates conditions that exacerbate wildfires in the west, which, in addition to the direct threat they pose to people in the area, cause high levels of particulate and other air pollution that affects not only air quality nearby, but can impact air quality as far as the northeast, as was the case this past summer.
As Congress works toward passage of the bipartisan infrastructure bill and the reconciliation package, the stakes are high for both climate and air quality. Congress and the federal agencies have key roles to play in the Biden administration’s “whole-of-government” approach to addressing these problems.
For example, funding for air quality monitoring is critical to identifying and addressing areas with serious and persistent air quality problems and reliable and timely information is necessary to protect public health and the environment and support U.S. EPA’s ongoing work. The air quality monitoring system in the United States suffers from underinvestment as funding has failed to keep pace with costs to both maintain the system and satisfy increasing demands for information. CATF recently submitted a letter to the chairs of the Senate Environment and Public Works and House Energy and Commerce committees encouraging them to include $500 million in funding to update and improve the air quality monitoring system in the U.S.
On the executive agency side, U.S. EPA is faced with several important regulatory decisions under the Clean Air Act in the coming year. EPA must follow the science and the law by expeditiously reviewing and strengthening the national ambient air quality standards for fine particulate matter and ozone, two of the most important pollutants of concern. We also encourage the agency to address the persistent problem of interstate transport of these pollutants, particularly ozone, as sources in upwind states continue to impact the air quality experienced by residents in downwind states. And, experience with existing standards also supports strengthening the rules for power plant air toxics emissions, including for mercury, nickel, and other metals. All of these actions will result in protections for the most vulnerable Americans and our environment.
It is also worth recognizing the synergy between setting tighter standards to address pollutants like fine particulate matter and ozone and making progress on reducing greenhouse gas emissions. By pressing for cleaner methods, systems, fuels, and other options for production, manufacturing, energy, and transportation, we can often obtain reductions in emissions of both greenhouse gases and conventional pollutants, as rules that target one type of industry emissions can affect investment decisions that result in lower levels of other pollutants. The Biden Administration has committed, in Executive Order 13990, to evaluating a number of do-nothing or reversionary decisions taken in the last four years, and we urge EPA to follow through on these directives by strongly engaging all of the regulatory options it has available to improve air quality, particularly for fenceline communities. In doing so, the Biden Administration can show that it places a premium on clean air and blue skies, and is serious about taking action on air pollution, climate change, and environmental justice.