Rural air quality
Rural air quality refers to the presence of pollutants such as particulate matter, ozone, and gases emitted from various sources, including industries, power plants, and vehicles, in non-urban areas. Despite common perceptions of rural environments as having cleaner air, numerous factors contribute to air pollution in these regions, including dust from unpaved roads, livestock emissions, and agricultural activities that release ammonia and nitrogen oxides. Health professionals have identified significant health risks linked to exposure to these pollutants, prompting governments at various levels to implement strategies aimed at reducing rural air pollution.
Climate change has exacerbated these issues, as rising temperatures have led to increased ozone levels, particularly in areas like California's San Joaquin Valley, where geographical features trap pollutants. Here, agricultural practices and livestock emissions are notable contributors to air quality degradation. Efforts to combat rural air pollution include the establishment of regulatory frameworks, such as the National Ambient Air Quality Standards (NAAQS), and the implementation of local rules to monitor and control emissions from large agricultural operations. However, challenges persist, including the influence of industrial activities in sparsely populated areas and the socioeconomic dynamics that may limit the ability of rural communities to advocate for cleaner air. Understanding the complexities of rural air quality is essential, given its implications for public health, agricultural productivity, and climate resilience.
Rural air quality
Definition
Pollutants affecting the quality of rural air include particulate matter, ozone, and emissions from industries, power plants, and vehicles. Air in rural areas is also polluted with dust from unpaved roads, livestock gases, and agricultural products containing ammonia, nitrogen oxide, sulfur dioxide, and other toxic chemicals. Urban emissions transported by wind currents also pollute rural air.
Medical professionals identify health risks associated with rural residents’ contact with harmful pollutants in air they breathe. Local, state, and national governments worldwide consider strategies to control rural air pollution and restrict emissions. The US Environmental Protection Agency (EPA) developed the National Ambient Air Quality Standards (NAAQS), which is frequently used to measure pollution levels in rural areas.
Significance for Climate Change
During the 1990s, temperature increases associated with global warming exacerbated pollution in rural locations, resulting in the EPA issuing stricter emission standards. This federal regulation alerted the public that rural areas experienced severe air pollution, contrary to many people’s perception of the countryside as having cleaner air than do urban sites. Many agricultural organizations, including the American Farm Bureau Federation, stated that emission standards would impede farming and resisted compliance. At that time, most pollution control agencies did not enforce attainment, and rural air quality declined.
By the early twenty-first century, ozone, particulate matter, and smog represented significant pollution hazards to rural residents. Vehicle exhaust and other emissions chemically react with sunlight to produce ozone. Officials recognized that ozone pollution was created both by rural emissions and by urban industries releasing greenhouse gases (GHGs) that drifted into rural areas and contributed to raising temperatures conducive to generating ozone. As smog accumulated in rural areas, the EPA adjusted prior NAAQSs, considering air safe if 1 cubic meter did not exceed a maximum of 15 micrograms of particulates and 75 parts per billion of ozone.
The San Joaquin Valley, an agricultural region in central California, suffers poor rural air quality. It is an interesting case study of the struggle of one location to improve air quality over a period of decades. Mountains in that area restrict pollutants’ movement. Smog fills the valley. In 1999, a coalition consisting of such groups as Medical Advocates for Healthy Air had focused on poor air quality, as global warming conditions heated the San Joaquin Valley. That alliance estimated that particulates caused thirteen hundred deaths annually in the valley. Citing provisions of the Clean Air Acts (1963–1990), the coalition legally pressured officials in the San Joaquin Valley Unified Air Pollution Control District to devise programs to protect rural air quality and seek attainment of federal standards.
The San Joaquin Valley Unified Air Pollution Control District monitors wineries’ boilers, verifying that they do not discharge excess carbon and other pollutants while burning. Approximately 2.5 million dairy cattle in the valley contribute to smog by expelling gas containing volatile organic compounds created by microorganisms during digestion. These compounds convert into ozone in the atmosphere. In the twenty-first century, cows surpassed cars in importance as polluters to air quality in the location. The San Joaquin Valley Unified Air Pollution Control District’s Rule 4570 requires dairies stocking one thousand or more cattle to comply with air quality regulations in order to secure permits. The Air District continued to operate in 2023 as a public health agency whose mission is to seek strategies to improve the health and quality of life of the residents of the eight California countries the organization serves through air quality management. In 2022, however, the EPA stated the San Joaquin Valley remained home to some of the United States' worst air quality.
Increased ozone associated with climate change harms tomato cultivation in the San Joaquin and Sacramento Valleys; tomatoes generate several hundred million dollars yearly for the region. Rural air pollution affects crop yields globally. Despite these damages, nonattainment of EPA standards often prevails. Exemptions allow commercial agriculturists to use machinery and diesel fuels that emit pollutants that are harmful to air quality and also intensify global warming. Livestock confinements produce methane, hydrogen sulfide, and other pollutants that contribute to climate change while lowering air quality.
Industries often select sparsely populated rural locations for their factories. Many rural residents represent lower socioeconomic classes and lack the influence and resources to prevent industrial intrusion. Factories generate heat that traps GHGs and smog above rural areas. Industrial particulates damage fields and forests. Commuters’ vehicles, moving between rural and urban areas, worsen air quality in the countryside. The San Joaquin Valley Unified Air Pollution Control District utilizes the Indirect Source Rule to reduce rural development pollutants, charging fees for construction of subdivisions and buildings with substantial square footage. Officials invest those funds in alternative fuels and air quality and climate control projects. This is an example of how the Air District combined management strategies with entrepreneurial enterprise.
Wildfires and domestic fires for cooking or waste removal add smoke and ozone to rural air. Fires set to clear rural land destroy carbon-absorbing plants. In Asia in 2007, as temperatures warmed, a combination of GHGs and air pollution, referred to as the Asian Brown Cloud, contributed to melting approximately forty-six thousand glaciers, causing flooding and depleting long-term water sources in rural areas. This pollution traveled to other continents. The Asian Brown Cloud continues to occur annually from November through May over parts of Asia. The California Air Resources Board and the National Aeronautics and Space Administration (NASA) deployed aircraft in 2008 for scientists to evaluate air pollution movement and how it affects the atmosphere and climate changes. The California Air Resources Board continued, in 2023, to focus on the challenges affecting the quality of air in California and setting emissions standards. NASA continues to use aircraft to monitor air quality, but has also long relied on satellites orbiting Earth as well.
Bibliography
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Rodriguez, Cresencio. "California Has Some of the Worst Air Quality in the Country. The Problem Is Rooted in the San Joaquin Valley." PBS, 16 June 2022, www.pbs.org/newshour/nation/california-has-some-of-the-worst-air-quality-in-the-country-the-problem-is-rooted-in-the-san-joaquin-valley. Accessed 19 Jan. 2023.
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