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Air, Climate, and Energy

Introduction

American communities face serious health and environmental challenges from air pollution and the growing effects of climate change, both of which are intricately linked with energy options.

Building on 40 years of achievement in air pollution research that has led to landmark outcomes—including healthier communities and longer life expectancies—EPA researchers are exploring the dynamics of air quality, global climate change and energy as a set of complex, yet interrelated, challenges.

This section highlights some of EPA's many achievements advancing Air, Climate and Energy science during 2010, including: a year-long celebration of 40 years of clean air science achievements in support of the Clean Air Act that brought researchers, stakeholders and the public together to explore past achievements and emerging research efforts; the announcement of a major new partnership to develop clean cookstoves for the developing world; the launch of a major near-roadway study investigating the links between local air pollution and asthma; the development of a model illuminating how controlling man-made sources of air pollution also may reduce compounds released into the air from vegetation; and much, much more.

Celebrating the Past, Looking to the Future: Air Science 40

EPA provided a year-long look at clean air science achievements and ongoing research.

2010 marked two important milestones in the nation's history of protecting human health and the environment: the 40th Anniversary of the establishment of the U.S. Environmental Protection Agency and the passage of the landmark Clean Air Act. The Agency celebrated both occasions through the Air Science 40 program, a series of lectures, Webinars, and other public events centered on science communication and highlighting how advances in clean air and human health science have contributed to cleaning up the nation's air and improving the health of its citizens.

Throughout the year, Air Science 40 programs highlighted four decades of clean air science accomplishments. Leading EPA scientists and their partners also shared ongoing research efforts to develop a deeper understanding of the complex, often far-reaching, new challenges the Nation and local communities face in managing air quality. Emerging issues, such as the multitude of pollutants in the air, and the complex interactions between air quality and a changing climate, were explored and shared by leading experts.

To kick off the celebration, EPA's Clean Air Research Program co-sponsored an international conference on the latest science exploring the connections between health risks, sources of air pollution and their emissions, and how those risks might be minimized. Air Pollution & Health: Bridging the Gap From Sources to Health Outcomes was held March 22-26, 2010, and was sponsored by EPA and its partners, the American Association for Aerosol Research Exit EPA Disclaimer, and the Air and Waste Management Association Exit EPA Disclaimer.

Following the kickoff in San Diego, Air Science 40 continued with Congressional briefings, regional presentations, and a seminar and Webinar series. Each event provided the opportunity for EPA scientists and their partners to share the latest research efforts and findings that are adding to a 40-year foundation of achievement.

A series of Webinars and presentations was conducted by investigators from EPA-supported Particulate Matter (PM) Research Centers. The PM Centers are leading research institutes focused on exploring the links between particulate matter and human health effects.
Presentations in the series included:

 The EPA Air Science 40 Seminars, co-sponsored by EPA and its partners, featured a number of presentations highlighting important clean air research findings that were shared with members of Congress and leading scientists.
Seminars included:

  • Air Quality in a Changing Climate
    What the Future Holds for the Air We Breathe
    Co-sponsored by the American Geophysical Union
  • Clean Air for All?
    Air Quality Across Social and Spatial Lines
    Co-sponsored by The American Thoracic Society
  • Air Pollution—A Matter of the Heart
    How Polluted Air Causes Cardiovascular Disease
    Co-sponsored by the American Heart Association
  • Breathe Cleaner, Live Longer
    Understanding Air Pollution After 40 Years
    Co-sponsored by the American Heart Association

Since the establishment of EPA in 1970, and passage of the Clean Air Act Amendments the same year, EPA’s Clean Air Research has provided the scientific information, tools, and technology to reduce and control air pollution. 2010 was a year to celebrate those accomplishments and look toward the future.

Better Burning, Better Breathing: Cleaner Stoves

EPA and partners will continue the effort to develop safer, lower emission solid-fuel cookstoves.

On September 21, 2010, EPA Administrator Lisa P. Jackson joined Secretary of State Hillary Rodham Clinton and a number of partners to announce a major effort to combat problems associated with cookstoves. Speaking at the Clinton Global Initiative in New York, Secretary Clinton announced that the U.S. Government was pledging $53.32 million—including a $6 million contribution by EPA—for the Global Alliance for Clean Cookstoves Exit EPA Disclaimer.

Led by the United Nations Foundation, the Global Alliance for Clean Cookstoves aims to save lives, improve livelihoods, empower women, and combat climate change by creating a thriving global market for clean and efficient household cooking solutions. The Alliance’s goal is to create the market and distribution conditions necessary for 100 million households to adopt clean cookstoves by 2020.

EPA’s involvement was in part sparked by ongoing research conducted by EPA scientists and engineers who tested a number of household cookstoves and fuel combinations for performance and air pollution emissions. The work was done to support the Partnership for Clean Indoor Air (PCIA), an association of more than 370 organizations contributing their resources and pooling their collective expertise to reducing smoke exposure from cooking and heating practices. PCIA was launched in 2002 at the World Summit on Sustainable Development in Johannesburg.

The objectives of the EPA study under the Partnership were threefold:

  1. Determine if some cookstove designs have improved fuel efficiency and lower pollutant emissions as compared with traditional “three-stone fire” (three stones placed around a fire to hold up a pot) found in many kitchens in the developing world.
  2. Provide useful cookstove performance and emissions information to PCIA partners and others supplying stove technology to developing countries.
  3. Compare test results using the Water Boiling Test protocol with those of a PCIA partner, Aprovecho Research Center in Cottage Grove, Oregon.

Research results from the study, presented in the paper “Solid-Fuel Household Cookstoves:  Characterization of Performance and Emissions” (Biomass and Bioenergy Journal February 2009;33(2)) showed that some stoves currently used in the field offer the benefits of improved fuel efficiency and lower pollutant emissions compared with traditional cooking methods. Stoves with lighter, less dense materials exposed to the heat of the fire tended to cook faster with better fuel efficiency and lower pollutant emissions.

The study provided an independent evaluation of 14 stove/fuel combinations with an emphasis on modern cookstoves designed to reduce harmful emissions and improve fuel efficiency. It illustrated the importance of testing stoves, and presented useful information for improving the design of stoves. Test results using the latest stove technology had not been reported in the peer-reviewed scientific literature before. The study also shows that stove-testing results can be replicated between laboratories, and offers recommendations for improving the ability to replicate results.

As part of the newly announced Global Alliance for Clean Cookstoves, EPA researchers and engineers will continue to advance their work, teaming up with partners across the globe to address critical areas such as stove testing and evaluation, cookstove design innovations, and health and exposure assessments to calculate the benefits of improved stoves. 

Exploring the Links Between Air Pollution and Asthma

EPA scientists and partners teamed up to examine road-related air pollution and susceptibility to asthma.

Can living near a highway make you more susceptible to asthma attacks? EPA scientists, together with partners from the University of Michigan, teamed up in 2010 to examine this question through the Near Roadways Exposure to Urban Air Pollutants Study (NEXUS).

Beginning in the fall of 2010, scientists began conducting a comprehensive asthma trigger study that will collect and use data from more than 60 children living in Detroit who suffer from asthma. Scientists will look at the mixture of pollutants that originate from Detroit-area highway traffic to determine how the pollution affects children with asthma. Data collected from air near major highways, as well as in homes and schools, will shed light on the mixture of air pollutants that affect asthma and overall health.

EPA scientists are working with partners from the University of Michigan and scientists from across several scientific fields to track air pollution over its entire lifecycle, from identifying its various sources to its ultimate effects on human health.

Partnerships at Work

To help determine the significance of near-road emissions/exposures and related health risks from mobile sources, EPA grantees developed a testing facility that allows for a controlled inhalation exposure to freshly diluted and mixed diesel exhaust (PDF) (4 pp, 394K, About PDF).

Building on lessons learned from past EPA-led research on near-roadway air pollution, NEXUS will include studies of air pollutant sources, near-roadway air pollution levels and behaviors (PDF) (2 pp, 415K, About PDF), and indoor air quality. During the study, scientists also will compare the toxicity of various air pollutants and conduct an epidemiological analysis of the health effects of air pollution. 

In addition to Detroit’s many heavily travelled highways, researchers will be able to look at pollution from other sources, including coal-fired power plants, metal refineries, and other heavy industries. They’ll also be able to examine the mix of airborne substances (including mold, pet dander, and tobacco smoke) in study participants’ homes and at several schools to compare those levels with the measurements taken at outdoor ambient air quality sampling sites.

The NEXUS project is already providing a major benefit to the local community. The project has created financial opportunities for Detroit residents, employing community members in data-gathering efforts and participant interviews. The training that participants receive will prepare them for future work in scientific research.

Furthermore, families participating in the study are being given access to the data collected from their homes. Researchers are working with a partner community group—Community Action Against Asthma—to help participant families gain access to health care and information to help them reduce asthma triggers in their homes.

When NEXUS’ data-collection phase ends in 2011, scientists plan to look for epidemiological patterns so they can answer such questions as:  What pollutants are most strongly associated with asthma? The data also will help scientists test and improve air quality models. By linking data from the ambient sites with data collected from Detroit homes and schools, scientists will be able to better determine how the ambient air is contributing to residents’ overall exposure to pollutants, and how to better predict health effects caused by air pollution.

Knowing which chemicals are the most harmful will allow policymakers to make better-informed decisions about clean air policies in their communities; targeting specific chemicals, for example, makes it easier for industry to comply with new clean air regulations.

Trees and Air Pollution

EPA modelers and partners show how controlling man-made sources of air pollution also may reduce compounds released into the air from vegetation.

EPA researchers have discovered that controlling man-made sources of air pollution will have the added benefit of also reducing air pollution formed from compounds released from trees and plants.

Trees and plants release more than just oxygen into the atmosphere as a result of photosynthesis. They also release a variety of gases that contribute to air pollution. In fact, the planet’s vegetation accounts for about two-thirds of the pollutants known as volatile organic compounds (VOCs) emitted globally.

In the study, published in the May 15, 2010 issue of Environmental Science & Technology, EPA researchers and partners quantified for the first time how emissions from vehicles, industry, and power plants interact with natural emissions from vegetation to change the composition and makeup of chemicals in the air…for the worse.

The implications of the study are considerable, suggesting that if people can control man-made sources of emissions, they can indirectly affect the formation of naturally derived atmospheric pollutant particles.

Using computerized air quality modeling, investigators conducted simulations of natural and human-related pollution in the United States. When scientists took man-made pollutants out of the simulation, there was a 50 percent drop in pollutants from trees and plants in the Eastern United States. These pollutants, known as secondary organic aerosols (SOAs), are produced by sunlight when VOCs from trees, plants, cars, or industrial emissions interact with other airborne chemicals. SOAs are important for the formation of two regulated air pollutants, particulate matter and nitrogen oxide, a greenhouse gas.

The study suggests that roughly one-half of the “natural” SOAs in the Eastern United States form only when there is enough man-made pollution around.

The model can guide the development of strategies that can control atmospheric chemistry. Over the last 40 years, similar EPA research efforts to develop a better understanding of clean air science have led directly to policies widely credited with better air quality, which in turn reduces hospitalizations, worsening levels of asthma, cardiac events, and even deaths.

The research also can guide EPA to develop more refined and focused standards and strategies for effectively and efficiently decreasing pollution. This is just a first step in gaining an understanding of the complexity of the atmosphere. The research may have implications for future air pollution management strategies as well.

Scientists predict climate change will stimulate the growth of trees and plants and extend growing seasons, resulting in even more emissions from natural sources. By controlling man-made emissions, the impact of emissions from trees and plants may be reduced.

Expanding Atmospheric Modeling Capabilities to Protect Human Health and the Environment

EPA scientists incorporate cutting-edge science and meteorology into a widely-used air quality model.

In 2010, EPA scientists worked to incorporate cutting-edge air quality science and meteorology and additional capabilities into the Agency’s popular Community Multiscale Air Quality (CMAQ) model, which has been used around the world for more than 10 years to protect human health .  

Slated for release in September 2011, version 5.0 of CMAQ adds a new online capability—namely a “coupled meteorology-chemistry option” — to the air quality model that is used by EPA and states for designing emission control strategies needed to meet and maintain the National Ambient Air Quality Standards. An earlier version of the model is used by the National Weather Service to produce daily U.S. ozone air quality forecasts.

The “coupled model” will better represent the physical and chemical processes occurring in the real world by properly simulating the feedbacks between meteorology and air chemistry so scientists can better understand not only how weather conditions affect the chemistry, but also how air chemistry can affect and change weather conditions.

In this new modeling framework, meteorology data is updated on the fly, allowing scientists to use the model to look at smaller, finer resolution settings, such as individual towns and cities. Furthermore, while CMAQ has been used to assess air pollution problems at regional and continental scales, this new coupled model will allow researchers to expand the spatial scale to the northern hemisphere, thereby helping answer questions about the intercontinental transport of air pollution and interactions between air quality and climate change.

As CMAQ is already used world wide to help shape air quality management, the anticipated updates will enable regulators to better protect human health and the environment.

Modeling Shows Influence of Climate Change on Ozone Air Pollution

EPA partners show how climate change may offset some of the benefits of emissions reductions programs.

As we face the reality of global climate change, the need for new advances in modeling systems and methods for assessing the impacts of climate on air quality is increasing. Robert Harley and his colleagues at the University of California, Berkeley, recently used the CMAQ modeling system to assess these impacts on future air quality in California. This research, which is funded through the EPA's Science to Achieve Results (STAR) grant program, led to new insights about the relationship between air pollution and climate change.

Harley and his team of scientists show that climate change has the potential to offset some of the benefits of emissions reductions programs. The CMAQ system was used to simulate changes in tropospheric ozone levels (PDF) (14 pp, 1.8MB, About PDF) Exit EPA Disclaimer resulting from future changes in pollutant emissions. By 2050, technological changes and an aggressive set of emissions controls are predicted to decrease ozone pollution. The magnitude of that decrease, however, is significantly reduced when the effects of climate change are considered. In fact, ozone levels are predicted to increase in the San Francisco Bay area.

This EPA-funded research is helping air quality managers plan to meet health-based air quality standards in the future. Poor air quality and high ozone levels already exist in many regions of California, and higher temperatures predicted with climate change could make this problem worse. Existing regulations may need updating to ensure public health is protected on a warmer planet.

Harley's work also explored the effect of higher temperatures on volatile organic compound (VOC) emissions. Cars and other mobile sources are the dominant anthropogenic source of VOCs in California, and the research team measured the contributions of two important types of vehicle-related pollution: tailpipe emissions and liquid fuel evaporation. The relative importance of evaporative sources could increase in the future as maximum daily temperatures rise.

The research demonstrates several possible influences of climate change on air pollution, and the need to consider these effects in air quality management. The air quality assessment approach developed by Harley's group can be utilized by local and state regulators to meet national air quality standards effectively and efficiently.

Air, Climate, and Energy

2010 Accomplishments – In Brief

EPA-Funded Particulate Matter (PM) Research Center Assesses Ultrafine PM Health Effects

EPA-funded research at the Rochester PM Research Center and the Southern California Particle Center found that ultrafine particulate matter (UFP) is easily transported throughout the body beyond the cardiopulmonary system. Tissue and cell analysis shows evidence for the translocation of UFP to the liver, kidneys, and central nervous system. Exposure to concentrated airborne PM led to inflammatory responses and oxidative stress in key organs. Surprisingly, there is potential for UFP to cross into the circulatory and lymphoid systems, which could allow the particles to reach sensitive sites, such as the heart, spleen, and bone marrow.

Age and disease were found to be critical modifying or susceptibility factors. Researchers also found that impacts on the circulatory system could be worse for those with atherosclerotic vascular disease, such as that seen in type 2 diabetes. The Rochester Center's 2010 report, Assessment of Ambient UFP Health Effects: Linking Sources to Exposure and Responses in Extrapulmonary Organs (PDF) (35 pp, 214K, About PDF), integrates the results of many of the Center's PM health effects studies to show that ultrafine particles can cause significant health effects in the respiratory, vascular and cardiac systems – especially in older adults and people with atherosclerotic vascular disease.

Developing Methods for More Refined Measurements of Air Pollutants

Three EPA-funded research efforts led to the development of technologies for the continuous measurement of PM composition. Results will provide new techniques for state and local air pollution monitoring networks, and for conducting intensive field studies. Accomplishments include:

  • A new mobility spectrometer developed by an EPA grantee at the University of California, Davis, that can analyze distributions of molecular ions, charged particles, and macromolecules or molecular clusters. The device, called Cross Flow Ion Mobility Spectrometry (CF-IMS) (PDF) (8 pp, 840K, About PDF), is lightweight, low cost, and can analyze the composition of the gas phase continuously with high-mobility resolution.
  • An EPA grantee at the Georgia Institute of Technology tested a cost-effective monitor that measures water-soluble components of urban aerosol. A potassium and a sodium ion-selective micro-electrode was integrated with a Particle-Into-Liquid-Sampler for online measurements and deployed near a prescribed burn in rural Georgia. New techniques for detecting the water-soluble metals iron sulfate and copper were also tested successfully. Results from the trace metals tests showed an improvement in measurement sensitivity and temporal variability over the traditional filter-based approach.

EPA-Funded Researchers Map Heat-Related Trouble Spots

EPA-funded researchers used a novel approach to develop a map showing where people are more vulnerable to dangerous heat waves.

Although heat waves and hot weather are known to lead to increased deaths and illness, what is not well understood is why some people are affected more strongly by heat than others. With the frequency of heat waves expected to increase in much of the world due to climate change, the links between heat and health become especially important.

A team of EPA grantees collaborated to map vulnerability to heat in the United States by analyzing 10 “vulnerability factors,” including demographic data, air conditioning prevalence, vegetation cover, and diabetes prevalence, in nearly 40,000 census tracts across the United States.

The results of the study, which were published in Environmental Health Perspectives, (Reid CE, O’Neill MS, Gronlund CJ, Brines SJ, Brown DG, et al. 2009  "Mapping Community Determinants of Heat Vulnerability") identified some of the most vulnerable areas of the country, providing critical insight to guide further research and the formulation of strategies to protect public health.

EPA Partners Develop Models and Strategies for Smart Growth in a Changing Climate

Adopting "smart" urban planning strategies is a non-traditional pollution control strategy that has received attention from EPA grantees. Land use management and transportation policies are tools that state and local officials can employ to help mitigate the effects of climate change on air pollution. In addition to developing air quality metrics for evaluating different growth development strategies, here are some of the critical findings:

  • Road pricing and urban growth boundary policies could reduce vehicle miles traveled and ozone precursor emissions in Austin, Texas.
  • A new model for developing sustainable communities was applied to a county in North Carolina to demonstrate neighborhood "livability" and air quality.
  • Regional scale modeling predicted future transportation needs and land use to evaluate the impacts of climate change and, the built environment, and transportation technology choices on air quality across the upper mid-western U.S. The results confirmed substantial benefits from the Tier-II vehicle emissions regulations through 2050 and that smart growth strategies could result in significant improvements to air quality in the future.

Climate Change Predicted to Increase Flooding and Waterborne Disease Risk

Research conducted by EPA grantees investigated how climate change will impact waterborne disease (PDF) (23 pp, 667K, About PDF) risk in the Great Lakes region. The study focused on how heavy precipitation events are expected to change during the 21st century. These heavy precipitation events are associated with flooding and sewer overflow conditions that are conducive to the spread of waterborne disease.

The researchers calculated that the occurrence of precipitation events heavy enough to cause sewer overflow into Lake Michigan would increase by 50% to 120%. This could have a great impact on the beaches of Lake Michigan, especially their availability for recreational use. Similarly, given that Lake Michigan is a drinking water source for millions of people, this suggests another way in which climate change threatens human health.