Case study questions

Description

Lesson 7
Activity 1, Air Pollution Health Warning Poster

Take the knowledge you learned about ozone in Task 7 and build on that. You will need to do some research and might want to start on the Air Pollution site.

Then, design a poster to inform the public about a specific area of air pollution. This could be related to ozone levels, indoor air pollution, chemical pollutants in the environment, etc.

Activity 2, Carbon Labs #1, #2, #3

At the end of each lab there are questions for consideration.

Third, It’s In the Air Lab (instructions in Important Documents called: “aerosol_lab_activity”)

Fourth, Case Study

Complete the case study, On a Clear Day You Can See Forever (PDF). It is attached to this lesson.

Submit your poster and case study here.

On a Clear Day You Can See Forever

by David W. Kelley Department of Geography University of St. Thomas

and Rebecca Helgesen Minnesota Pollution Control Agency

Figure 1a. On a bright March  morning with an Air Quality Index (AQI) reading of , downtown St. Paul and the Minneapolis skyline are clear. Photo: mpca staff

Part I—It’s a Small, Small World

Figure 1b. On a hot June  day with an AQI of , a haze dims the St. Paul landscape and Minneapolis disappears. Photo: mpca staff

December , , dawned clear and cold in London, England. Te air was damp and stagnant. Heavy black smoke rose from chimneys as Londoners lit the coal they burned to cook and heat their homes. Fog began to roll in. By dusk, the smoke-filled fog had turned an impenetrable yellowish black.

By the time the smoky fog lifted four days later, , Londoners were dead of heart and lung complications. Another , died during the following two weeks, as the persistent health impacts of the five-day fog

continued. When researchers compiled statistics, they estimated that during the next two months, , more died of causes directly related to that deadly fog.

Te culprit in London’s killer fog wasn’t the fog itself. It was thousands of tons of tiny particles that clung to the stagnant fog and filled residents’ lungs. Tick soot from the city’s coal-burning home hearths, diesel buses, and factories hung near the ground, trapped by a slow-moving temperature inversion. Black smoke concentrations measured during those five days reached more than  times normal levels.

For hundreds of years, Londoners have experienced discomfort related to particles in smoky fog (dubbed smog in ). Recently, it has become clear that those fine particles are more than uncomfortable.

Te most serious effects of small particles are associated with aggravation of heart or lung disease. Numerous studies have related particles in the air to increased hospital admissions, emergency room visits, and mortality. Aggravation of lung diseases, including asthma attacks and acute bronchitis, has been correlated with short-term exposure. In people with heart disease, particles have been linked to heart attacks and irregular heart rhythms.

According to Dr. Joel Schwartz of the Harvard School of Public Health, it’s not a small problem. By one estimate, , people in the U.S., primarily older adults, die prematurely each year when fine particle pollution increases to unhealthy levels. “Tis,” says Schwartz, “is larger than the death rate from breast and prostate cancer combined.”

Minnesota is a long way from the London of the s—or even the troubled cities of the industrial northeast United States. It has its own unique problems with smoke-related pollution, however, as documented in the following article.

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 1 Te material on this page is excerpted from “Out of a Clear Blue Sky: Regional Haze Mars Scenic Vistas, Even in Minnesota” by Ralph Pribble, Minnesota Environment, Summer 2003, Vol. 3(3), p. 10.

Air pollution affects not only urban areas, but national parks and wilderness areas as well. On bad days, “regional haze” cloaks some of the United States’ most treasured “purple mountain majesties” in brown or white gauze. Many of the  million Americans who each year visit parks such as the Grand Canyon or Glacier National Parks are surprised to find they can’t get a clear view of the scenic wonders they have come to see.

Te cause might surprise outdoor enthusiasts. It

is fine particles similar to those that blight our urban skies. Some haze is natural, part of prevailing climate dynamics. After all, the Great Smoky Mountains were known by that name long before the mid-South industrialized. Dust, organic compounds, smoke from forest fires, and humidity figure into what is considered natural (unpolluted) visibility.

In pre-settlement days, the farthest a person could expect to see on a clear day was between  to  miles in the Western U.S., and  and  miles in the East. Today, however, typical visual range in the West is  to  miles. In the East, it’s only  to  miles. Te culprit in this deterioration appears to be human activities.

In , the U.S. Environmental Protection Agency (epa) issued regulations designed to further reduce haze and protect visibility, as well as specific programs to reduce particle air pollution overall.

Figure 2. A Forest Service improve automated monitoring station just outside the bwcaw shows the distinct difference between a clear day (more than  miles visibility, above) and a hazy one (less than thirty, below). Photos: usda Forest Service

For example, the U.S. Department of Agriculture National Forest Service’s improve (Interagency Monitoring of Protected Visual Environments) network collects air samples and provides monitoring data on visibility and fine particulates at  Class I locations, including Voyageurs National Park and the Boundary Waters Canoe Area Wilderness (bwcaw), both located in northern Minnesota.

Te equipment at improve sites includes automated samplers to measure airborne particles and particle mass, along with light-monitoring equipment and a camera. According to Trent Wickman of the Forest Service’s Duluth office, “Te contributions of pollutants at the [bwcaw] are clear. A large portion is ammonium sulfates, which are pretty clearly tied to coal combustion.” He added there’s not sufficient data yet to provide trend analysis, but that “we’re getting to that point.”

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 2 Regardless of their source, trying to describe fine particles is like trying to describe animals to someone from another planet. Just as animals can be large or small, feathered or furred, dangerous or benign, particles can be varying sizes, solid pieces or liquid droplets, man-made or natural, dangerous or benign.

Some particles are emitted directly into the air, and some form in the air from chemical reactions of nitrogen oxides, sulfur oxides, volatile organic compounds, and ammonia. Particles can cling to moisture droplets or simply drift in the air. Scientists call particles “particulate matter,” abbreviated pm. Regulators generally divide particulate matter into two categories on the basis of size: pm and pm..

Questions

1. What do “pm” and “pm.” mean?

2. Which of these particles are the most harmful?

3. How do fine particles cause health effects?

4. What groups are most vulnerable to fine particle air pollution?

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 3 Part II—Life’s Better at the Cabin

Particles are both urban and rural

Fine particle pollution is everywhere, as are the combustion processes that create them. Tere is no way to avoid it. Te smokestacks and tailpipes of cities and towns produce a large part of pm, but sources exist in rural areas as well. Fine particles can ride the wind to locations thousands of miles from the original sources and stay in the air for a long time.

Even rural areas, including remote national parks, are plagued by “regional haze,” a benign-sounding term for fine particle pollution that has blown in from elsewhere and obscures famous views. If tourists at Arizona’s Grand Canyon, South Dakota’s Badlands, and Tennessee’s Great Smoky Mountains pick the wrong day to visit, they find the dramatic scenery veiled by a gauzy haze. Although not as badly affected as other areas, Minnesota’s Voyageurs National Park also shows signs of regional haze.

Figure 3. Measurements based on one year of monitoring at urban Minnesota sites.

One goal of the Clean Air Act is to restore the view of these national treasures to the clarity that onlookers enjoyed before the advent of man-made air pollution. Class I areas, as defined in the Act, are  national parks, monuments, and wilderness areas in the United States. Even remote, far-north Class I areas such as Voyageurs and the bwcaw become hazy from transport of fine particles high in the atmosphere, where they can be carried long distances.

Short-term exposure is enough

London’s  fog carried very high concentrations of fine particles. But can fine particles at elevated levels really do so much damage so quickly? Recent research suggests that they can. Measurable changes in the body may take place within hours of increased exposure, particularly in people with existing cardiovascular or respiratory conditions.

Te Health Effects Institute, an institution jointly funded by the epa and industry, commissioned a

nationwide study in the late s on the short-term effects of air pollution, the National Morbidity, Mortality and Air Pollution Study (nmmaps). Te study found strong evidence linking daily increases in particle pollution to increases in mortality in the 90 largest U.S. cities (including the Twin Cities), particularly from heart and lung diseases.

Re-analysis of the study due to a statistical problem did not change the basic conclusions:

• Tere is an association between short-term increases in particles and death, as well as hospital admissions for heart diseases and chronic obstructive pulmonary disease.

• Tis association is strongest for respiratory and cardiovascular causes of death.

• Te association was not attributed to other air pollutants.

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 4 Over  years ago, researchers at the Harvard School of Public Health released the results of a study following , adults in six cities during a dozen years (Dockery et al., ). Tey found that people in the city with the highest fine particle pollution had a  percent higher risk of death due to cardiopulmonary causes than the residents of the least-polluted city.

Another study supports the Harvard findings. In the March  th 2002 issue of the Journal of the American Medical Association, Dr. George Turston of the New York University School of Medicine and Brigham Young University researcher C. Arden Pope reported on their landmark study that followed a half million

people in  U.S. cities for  years (Pope et al., ). Comparing health data to air pollution records, they found that populations with prolonged exposure to particulate air pollution had significantly higher risk of dying of lung cancer and other lung or heart diseases.

“Long-term exposure to air filled with fine particles carries almost the same risk of lung cancer and heart

disease as breathing secondhand smoke over a long period,” says Turston. Tis wasn’t his only finding after years of pm research.

“We also found that, if you are aged  and older, you have a considerably increased risk of having a heart

attack within two hours of a high fine particle episode,” says Turston. “Tat risk doubles if you already have heart or respiratory disease.”

But it isn’t only older adults who are at risk, says Turston. He believes that babies from one month to one year are also more at risk, for three reasons: they breathe more air per pound of weight; they tend to have a high rate of respiratory ailments already, which leaves them more vulnerable; and they are developing rapidly.

As science zooms in on fine particles, we will learn more about their effect on us. But don’t expect the news to get better. “Basically,” says Turston, “everyone is at risk from air pollution—it’s just a question of how much.”

Te following material is excerpted from “Where Tere’s Smoke, Tere’s Smoke-Related Pollution” by Anne Perry Moore, Minnesota Environment, Summer 2003, Vol. 3(3), pp. 7–9.

When wildfires burn, the smoke stops here

Smokey the Bear never said it would be like this. Kids of all ages know they are responsible for preventing forest fires. What they may not know is that fire-related air pollution can have health consequences—for people living both nearby and thousands of miles away.

Wind sent smoke from the  Colorado, Arizona, and Canadian mega-fires across whole states. Te blowdown area in the bwcaw remains a tinderbox. In the spring of , grass fires in Minnesota raced across many communities, clouding the air with smoke. As summer heat and storms escalate, we can learn what to do if weather conditions send harmful wildfire smoke in our direction.

Smoke gets in your eyes

Ninety percent of wildfire-related emissions are carbon dioxide (a major contributor to global climate change) and water vapor. Te rest includes particles in a range of sizes. Fine particles remain suspended in the air from a few seconds to several months.

To help the general public and high-risk groups identify and reduce potential health problems related to wildfires and smoke exposure, experts in several western state agencies offer easy-to-understand, visibilitybased guidance. (See an example at the Oregon Department of Environmental Quality at

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 5 http://www.deq.state.or.us/aq/burning/wildfires/ wildfire-health.htm#using%20visibility.) Te bottom line: Te more visible the smoke, the more likely the health concern.

Tough these visibility guides were developed for local use, they apply far from active fires as well. Air emissions travel: Airborne arsenic from Beijing smelters turns up in Hawaii, U.S. factory pollutants land in Europe, Saharan Desert dust falls in the Caribbean. Wildfire pollution has the same airborne transmission potential.

For example, during the - El Niño, smoke from drought-related forest fires sent hundreds of Malaysians, Indonesians, and Brazilians to local clinics with respiratory complaints. Te larger the population downwind from any big fire, the greater number of people potentially exposed.

Te statistics are staggering. Each year forest fires worldwide emit an estimated:

Figure 4. During the summer of , powerful storms ripped through the Boundary Waters Canoe Area Wilderness, damaging nearly , acres of timberland. Controlled burns will be used to lessen the possibility of a massive fire. Photos: Superior National Forest

•  million tons of carbon dioxide

•  million tons of carbon monoxide

• . million tons of nitrogen oxides (a precursor of ground-level ozone)

• particulate matter

• hydrocarbons (such as benzene)

• aldehydes (such as formaldehyde)

• trace minerals

In the United States, according to the National Interagency Fire Center (http://www.nifc.gov/stats/wildlandfirestats.html), an estimated . million acres of wild land burned in , costing federal agencies $. billion to suppress.

Fire starter

Dry twigs, needles, and moss can combust if they connect with an electrical spark, a discarded cigarette or an abandoned campfire. High winds can fan flames over larger twigs and brush, followed by branches and logs—a perfect recipe for a very hot, very intense, multi-day burn.

Living forests are not exempt: they are vulnerable to severe fires during the growing season if two weeks pass without rain. Mother Nature “sets” fires, too: Lightning strikes are a significant cause of wildfires, particularly in late summer when the ground is dry.

Large forest fires scorch the soil and send burning embers up to five miles away. Once a forest canopy or large pile of logs is engulfed, a thick “plume” of pollutant-filled smoke rises into the atmosphere. In the best case, winds disperse the smoke. In the worst, wind transports the smoke to populated areas, then a

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 6 temperature inversion prevents it from vertical mixing. Wind and weather conditions can be predicted only up to  hours; after that, it’s anybody’s guess which way the wind, fire, and related pollutants will blow.

To better understand fire movement, near-real-time global fire mapping is helping scientists anticipate a wildfire event—and prepare for its impacts. Satellites originally designed to collect weather data can now observe and monitor dry areas, active fires, fire hot spots, burned areas, and air emissions (see the National Oceanic and Atmospheric Administration Web site for satellite photos at http://www.osei.noaa.gov/).

More than , U.S. weather stations collect and assess current wildfire conditions, produce fire danger maps, and make fire weather observations and next-day forecasts. State and federal agencies compile data into larger fire-assessment tools and cooperate with fire watchers worldwide.

Figure 5. Smoke from an Alberta, Canada wildfire in May  blows southward across the Great Lakes (seen in the lower right of this satellite photo), hiding much of Lake Superior from view. Photo: Te Seawifs Project, nasa/Goddard Space Flight Center and orbimage

Measuring PM in Minnesota

So, as an example, what is being done about it in the land of , lakes and numerous forests, located downwind from other particulate sources? Special pm. monitors are currently measuring the concentration of fine particles in the ambient outdoor air. Te Minnesota Pollution Control Agency (mpca) operates pm. monitors in Duluth, Rochester, St. Cloud, and several Twin Cities locations. Plans are in the works for monitors in other regions of Minnesota as well.

“We’ve already learned something interesting from

this monitoring,” says Rick Strassman, supervisor of the mpca’s air monitoring unit. “Unlike some other air pollutants, fine particle concentrations rise and fall rapidly throughout the day and night. Tis makes it a challenge to get timely word out to the public if they need to act.”

In Minnesota, sulfate is an important component of haze. Nitrate and organic carbon are significant in winter and summer, respectively. Since some fine particle pollution blows into Minnesota from

Figure 6. Tis composite photo of the St. Paul

skyline provides a visual comparison of two different levels of fine particles—pm. levels of µg/m (left) to µg/m (right). Notice the difficulty in seeing buildings in downtown St. Paul on the right half of the picture. Te daily standard for pm. is µg/m (micrograms of particles per cubic meter of air). Photo: Midwest Hazecam

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 7 other states and some is homegrown, monitors help the mpca learn where particles are coming from, when, and where they are headed. Imported and homegrown air pollution sometimes combine to create even less healthy concentrations.

So far, says Strassman, pm. rises to concentrations considered unhealthy for sensitive people (people with heart or lung disease, older adults and children) no more than a few days a year. “And, knock on wood, we’ve seen only one day when pm. has risen to the next category, unhealthy for everyone.”

Now that regional pm. monitors are connected to the mpca’s web site (this occurred in summer ), citizens in each monitored community are able to check local air quality by going to the mpca’s Air Quality Index (aqi) web page (http://aqi.pca.state.mn.us/hourly/). Te aqi signals if the air quality could adversely affect you or your family.

Te mpca also sends out e-mail Air Pollution Health Alerts when pm. or ozone (at ground level, another

air pollutant) rises to unhealthy levels. Since accumulation of pm. is not dependent upon summer sunlight as is ground-level ozone, pm. concentrations are watched  hours a day,  days a year.

When the aqi for pm. is headed for  and the “unhealthy for sensitive groups” category, do you stay home from work? Crawl into bed? Ignore it all?

Te best advice medical science can offer during times of high pm. is this: take it easy. Try not to overexert yourself, no matter who you are. Reduce the time you spend on outdoor exertion or substitute a less intense exercise plan (walking instead of jogging, for example). Tose with heart and lung conditions should especially play it safe, taking it easy when the aqi is in the “high moderate” category.

When particle levels are high outdoors, they can also be high indoors. To reduce particles, turn on an air conditioner or air cleaner (for more information on air-cleaning devices, see the American Lung Association web site at http://www.lungusa.org/air/aircleaners_factsheet.html). Don’t use a humidifier, ozone generator, or “energized oxygen” device, all of which could make matters worse. Reduce other indoor air emissions (cigarette smoking, cooking, burning wood, gas or propane in stoves or furnaces, vacuuming, burning candles or incense).

And while you’re taking it easy, remember to help cut off additional pm. at the source. We may not be able to control what blows into Minnesota, but we can control what we add to the air: e.g., drive less, mow less. As the Greek physician Hippocrates advised , years ago: “make a habit of two things—to help, or at least, to do no harm.”

Questions

1. Should wildfires be stopped altogether to protect our forests, our air, and our health?

2. What is the Clean Air Act?

3. What are the epa and mpca doing about pm?

“On a Clear Day You Can See Forever” by Kelley & Helgesen

Page 8 Follow-Up—Governor, Outgoing EPA Director Tout Clean Air Minnesota

It was a rarified atmosphere at the Science Museum of Minnesota on June , , as Governor Tim Pawlenty and outgoing U.S. Environmental Protection Agency Director Christie Todd Whitman joined representatives of industry, government, and the environmental community to promote Clean Air Minnesota.

Clean Air Minnesota, a program of the Minnesota Environmental Initiative (mei), is a partnership to voluntarily reduce air pollution. Te partnership (including major companies such as m, Andersen Corporation, Ford Motor Company, and Flint Hills Resources) was formed in response to recent air-quality alerts in the Twin Cities Metro area related to ground-level ozone.

If the Metro area exceeds federal pollution standards for ground-level ozone, it may be designated a “nonattainment area.” Tis designation triggers mandatory pollution controls that, according to the Minnesota Chamber of Commerce, could cost industry and consumers $-$ million each year.

“[Clean Air Minnesota has] recognized, with increased smog, with increased alerts, there’s a problem coming down the road,” Whitman was quoted as saying in the St. Paul Pioneer Press. “But instead of waiting for that problem to become a crisis, which would put you in violation of clean-air standards, you’re taking action.”

Te partnership’s initial efforts will focus on:

• Educating the public about air-quality threats and how to address them;

• Working with industries and small businesses (point and area sources of air pollution) to identify ways to reduce emissions;

• Lowering emissions from mobile sources; and

• Encouraging natural landscaping as an alternative to mowing.

Businesses and organizations ready to sign on to the Clean Air Minnesota approach can do so, if ready to commit to:

• Taking one or more actions to reduce emissions on days when an air pollution alert is forecast;

• Implementing one or more long-term activities to permanently reduce air emissions; and

• Assisting Clean Air Minnesota’s efforts to educate others about the importance of reducing air pollution and protecting air quality.

Find out more by visiting meis web page at http://www.cleanairminnesota.org.

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