TL;DR — As wildfires become an increasingly frequent part of our world due to a changing climate, forest management practices that maintain healthy forests play a vital role in protecting ecosystems, public health, and air quality. By implementing wildfire prevention strategies at the individual and agency levels, establishing resilient air quality monitoring networks, and understanding just how severely wildfires and poor air quality impact our national parks, we can work to preserve these landscapes and protect our air quality. 

The growing severity of wildfires and related air pollution

Wildfires are becoming increasingly frequent and severe in the world today given the rising temperatures and unpredictable weather patterns associated with climate change.

From 1984 to 2020, wildfires went from burning just 5% of land area in the United States to 23% annually. During the devastating 2020 wildfire season, more than 58,000 wildfires burned more than 1 million acres of forest.

Since 2015, the United States has seen an average annual increase of approximately 100 large wildfires. While this varies by region and year, the overall trend indicates a rise in the number of wildfires, the acreage burned, and the duration and intensity of fire seasons. (Source: Union of Concerned Scientists)

The role of forest management in preserving air quality

Forest management can be defined as practices that enhance the health of a forest, balancing the reduction of tree mortality with promoting healthy tree growth. 

One well-recognized tenet of forest management is the practice of prescribed burns. Because fires have been unnaturally suppressed for decades due to modern forest management practices and the expansion of the wildland-urban interface (WUI), many fire-dependent landscapes cannot regenerate as they naturally would and face overstocking, meaning too many trees are present for the amount of available resources. These forests become more vulnerable to drought, disease, insects, high tree mortality, and wildfires that are difficult to control.

The image above displays a prescribed burn carried out in Monterey, California to encourage the recovery of fire-dependent plant species that are endangered. (Image source: Flickr)

Prescribed burns help contribute to ecosystem health and reduce the buildup of vegetation that can easily spark during a wildfire — however, notably, they do produce local air pollution. Clarity customer Monterey Bay Air Resources District uses its network of Node-S air quality sensors to measure the air quality impacts of prescribed burns in the region, like the one shown above. 

A solar-powered Node-S air quality sensor is deployed to monitor air pollution resulting from a controlled burn in Contra Costa County, California. 

Other management strategies can be used in place of prescribed burns where fires may not be appropriate.

The importance of trees and forests in preserving air quality

Forest management is a vital tool in preserving air quality because healthy forests protect the air in a variety of ways: 

Effective wildfire prevention strategies for air quality preservation

Effectively reducing wildfires will require action at both the individual and government level.

Some best practices that individuals should follow include: 

Check out this article from the U.S. Department of the Interior to learn more about what you can do to prevent wildfires from starting.

While Smoky the Bear asserts that “Only you can prevent wildfires”, that isn’t quite true. Individual action is key, but to reduce both the occurrence and intensity of impact from wildfires government agencies must also put into place effective wildfire prevention strategies at the local, regional, state, and national levels, to reduce both the occurrence and intensity of impact from wildfires.

In addition to tangible strategies and policies to mitigate the factors that contribute to wildfire, this may include the preparation of community guides to disseminate information to the public about reducing high wildfire risk activities, and what to do to protect themselves in the case of a fire.

Agencies like the Bay Area Air Quality Management District have encouraged safe prescribed burning practices and implemented wood burning bans on days with high fire risk and/or unhealthy air quality levels to help reduce these negative impacts.

Other actions that forest managers may take include:

  • Creating open areas of land that have been cleared of vegetation and debris known as fire breaks
  • Allowing for more space between trees that have been planted to help prevent the spread of wildfire
  • Engaging in tree thinning, which removes dead or diseased trees to leave more space between existing trees and removing debris that can spark during wildfire
  • Focusing on planting fire, drought, and rot-resistant trees

Strategies to improve air quality in national parks

Many national parks — like Sequoia, Kings Canyon, Joshua Tree, and Yosemite in California — struggle with poor air quality, particularly in terms of ground-level ozone and particulate matter levels. These unhealthy levels pose a threat to both park visitors and rangers.

Research on 417 national parks demonstrates that:

  • 85% of parks have air that is unhealthy to breathe at times
  • 89% of parks experience haze pollution
  • 80% of parks are negatively affected by climate change
  • 88% of parks have soil and water affected by air pollution, which impacts sensitive species and habitat

The air pollution observed in national parks generally does not come from sources within the park but rather those polluting activities in their surrounding region, such as vehicle pollution that is blown in and may settle within valleys.

The two photos above, taken in the same location on two days without and with air pollution, demonstrate just how significantly air quality can affect visibility in national parks. (Image source: National Park Service)

In addition to harming visitors, poor air pollution in national parks also negatively impacts environmental and ecosystem health.

According to researchers at the University of California (UC) Merced and UC Riverside, unhealthy air may even be a significant driving force in the ongoing tree mortality crisis devastating the Sierra Nevada region. In addition to being directly toxic to plant life, pollutants like nitrogen oxides and ammonia can also lead to excess nitrogen deposition, which alters natural ecosystem functions and encourages growth of invasive species and algae blooms.”

— National Parks Conservation Association

Air pollution in national parks can also significantly reduce visibility and therefore impact visitor experience.

Protecting air quality in national parks

The air pollution experienced in national parks, like that in the rest of the country, comes from a slew of sources including fossil fuel combustion, oil and gas development, vehicle emissions, agriculture, and industrial emissions, among other sources. Fortunately, organizations like the National Parks Conservation Association working to support strong policy implementation and raise public awareness to keep air quality in national parks safe.

Because most pollution in national parks originates from outside the parks’ boundaries, the National Park Service must partner with air regulators, developers, and other stakeholders in a collaborative approach to reduce air pollution — which not only positively benefits these parks but also nearby communities.

Though not a direct threat to air quality, many initiatives exist to help reduce the amount of trash left in national parks, which has been a significant environmental pollution issue for a long time. Many initiatives involve promoting composting programs, which can help reduce greenhouse gas emissions and in turn, mitigate climate change and positively impact the air. To learn more about the links between air quality and climate change, as well as the air quality co-benefits that can help drive climate action, read our blog here.

Many national parks and conservation programs have also established extensive educational programs that help to raise awareness about air quality and other environmental issues and take the initiative to protect these resources. Taking into account these air quality considerations means protecting environmental health in national parks while still allowing visitors to enjoy their experience. Monitoring and maintaining air quality in national parks is also a key part of this picture.

The National Park Service participates in several air quality monitoring networks that focus on measuring ozone, visibility, particulate matter, nitrous oxides, sulfur dioxide, and mercury. These networks help the NPS to both understand air quality levels in individual parks and also understanding the air quality trends that impact parks nationwide. The NPS uses a combination of regulatory-grade monitors and low-cost air pollution sensors, which are implemented due to their lower price tag and ability to function well in remote locations, to capture a complete picture of air quality.

Interested in measuring air quality for cleaner air, improved physical and mental health, and a healthier climate? Get in touch with our team to learn more about our Sensing-as-a-Service solution for governments, businesses, and community organizations, using our Clarity Node-S monitors and Modules that do not depend on infrastructure like WiFi or power — making them especially resilient during environmental disasters.