Chapter 15: Atmospheric Pollution and Stratospheric Ozone Depletion

What does particulate matter range in size from? What size and below does it have to be for the EPA to regulate it? What are these called? Why are they of concern for air pollution scientists? Why are particules of 2.5 micrometers and smaller (PM2.5) an even greater health concern?

-0.01 micrometers to 100 micrometers -smaller than 10 micrometers -Particulate Matter-10, written as PM10 -not filtered out by nose and throat and can be deposited deep within respiratory tract -can travel further down respiratory tract and tend to be composed of more toxic substances

What percent of yearly lung cancer deaths are due to radon? How does the EPA suggest that we test this? How do we solve it if radon concentrations are high? What can other relatively inexpensive fixes include?

-14% -testing homes for airborne radon -increase ventialtion in home and ventilate underground space below house -sealing cracks in basement can be useful if radon is coming from underlying soil and bedrock

when did the federal appeals court agree to add carbon dioxide to the list of air pollutants under the Clean Air Act? In addition, what are commonly measured air pollutants with the potential to be harmful not officially listed in the Clean Air Act?

-2012 -mercury and volatile organic compounds

What is the acidity of rain? Why is it this acidic? What is acid deposition? What is acid deposition the result of?

-5.6 -reaction between water and atmospheric CO2 -deposition with a pH lower than 5.6 -largely human activity though natural processes like volcanoes can contribute to its formation

What percentage nitrogen is the atmosphere? All combustion in the atmosphere leads to formation of some...? How is nitrogen released into the atmosphere naturally and anthropogenically? Atmospheric nitrogen can play a large role in forming what within the atmosphere?

-78% -nitrogen oxides -motor vehicles and stationary fossil fuel combustion; forest fires lightning and microbial activity in soil -forming ozone and other components of smog

What percent of earth's atmosphere is nitrogen and in what combustion processes? What conditions allow proportionally more nitrogen oxide to be generated per unit of fuel burned? Therefore, in order to reduce nitrogen emissions what must be altered? What is the problem with this solution? Finding the exact mix of ______, temperature, __________, and other factors is a significant challenge.

-78, virtually all -hotter burning conditions and presence of oxygen -burn temperatures reduced and amount of oxygen controlled (sometimes utilized in factories and power plants by means of certain air pollution control technologies) -can result in less complete combustion, reducing efficiency of process and increasing amount of particulates and carbon monoxide -air, oxygen

Now that reforms have been made to amend chlorine concentration, why is it being reduced so slowly? What is thought to occur if stratospheric ozone concentrations do recover?

-CFCs are not so easily removed from atmosphere, and as a result, ozone depletion has continued to reach record levels in some areas (it will take a few decades to get accurate data) -number of additional skin cancers should eventually decrease

What are included as primary pollutants? How can VOCs be primary air pollutants?

-CO, CO2, SO2, NOx, suspended particulate matter, many VOCs -Gasoline is burned in a car and volatizes from liquid to vapor, some of which is emitted from exhaust pipe in uncombusted form, resulting VOC becomes primary air pollutant

In 1990 and again in 1995, scientists, policy makers, and academics collaborated on amendments to the __________ ______ _____ that would allow the free market to determine...? When was the freemarket program implemented and how many power plants are now covered under acid rain program of act? So far, each phase has led to significant reductions in..?

-Clean Air Act; determine least expensive ways to reduce emissions of sulfur dioxide -two phases between 1995 and 2000; 3000 -sulfur emissions

Which 3 countries are apart of the "black triangle"? Why was it caused this (hint: think about how the situation for levels of pollutants is less positive in countries other than the US)? For who and what has this proved to be damaging?

-Germany, Czech Republic, Poland -contain a lot of "brown" coal or lignite that provides fuel for coal fired power plants/ other industries, high sulfur content has caused this area to become most polluted in the world -human health problems (respiratory illness, etc), damaged forest ecosystems in past 40 years

In response to decrease in stratospheric ozone, 24 nations in 1987 signed what? What was the goal of this declaration? What did more than 180 countries eventually sign in 1996? Because of these efforts, is concentration of ozone increasing or decreasing?

-Montreal Protocol on Substances That Deplete the Ozone Layer -reduce CFC production by 50% by year 2000 -a series of increasingly stringent amendments requiring elimination of CFC production and total world use by 1996 -peaked at 4 ppb and is now decreasing

How are nitrogen oxides generically written (chemistry format)? What are included as the nitrogen oxides? Describe each.

-NOx -nitrogen oxide (NO) (colorless, odorless gas) -nitrogen dioxide (NO2) (pungent reddish brownish gas)

What does the NAAQS stand for? For each pollutant, what does the NAAQS specify? What occurs is a locality violates the air quality standard (such as for ozone)?

-National Ambient Air Quality Standards (NAAQS) -a concentration that should not be exceeded over a specific time period -it it does not make an attempt to improve air quality, it is subject to penalties

A newer description that has been given to combination of particulate matter and ozone? Where is it derived primarily from, contributing to its use in cities and throughout entire regions? What is the brownish tint characterizing these clouds caused by?

-atmospheric brown clouds -combustion of fossil fuel and biomass -presence of black or brown light absorbing carbon particles and/or nitrogen dioxide

How have nitrogen oxide emissions by cars in the US been significantly reduced in the past 35 years? With the use of this device, why can gasoline not contain lead? At the same time as this, what has also reduced emissions of nitrogen oxides?

-beginning in 1975 all new cars sold in US had to include a catalytic converter, reducing nitrogen oxide and CO emissions -precious metals in catalytic converter (mostly platinum and palladium) cannot be exposed to lead -improvements in combustion technology of power plants and factories

What is responsible for large emissions of nitrogen oxides and VOCs (two major contributors to smog formation) in urban areas? As a result of this, how have some municipalities tried to achieve lower smog concentrations? Some policies that have been made (particularly in Mexico city and China)? Did they work?

-cars -achieve lower smog concentrations by restricting car use -Mexico city, among others, instituted plans permitting people to drive automobiles every other day (in mexico city, plan did not have much of an impact) -China during 2008 Beijing Olympics, government successfully expanded public transport networks, imposed motor vehicle restrictions, and temporarily shut down number of industries to reduce photochemical smog and improve visibility (short period, it worked, but long term improvements in air quality have been harder to achieve)

What are chlorofluorocarbons? What items are they in and why were they put in them? Why were they used? What is wrong with them (what chemical do they introduce to the atmosphere)?

-chemicals used in consumer items with bad environmental effects -consumer items like aerosol spray cans and Styrofoam; considered "safe" since nontoxic and flammable -promoting breakdown of ozone in stratosphere; chlorine

CFCs introduce ____________ into the stratosphere. How can it break down ozone (include chemical formula)? What then occurs to pull the oxygen out of the chlorine monoxide? How does the chlorine act as a catalyst (since it is a single atom, and doesn't become a molecule for a long time)? What is the result of the presence of chlorine in the atmosphere?

-chlorine -attack to oxygen atom in ozone molecule, breaking the bond between that atom and forming chlorine monoxide and O2: (O3 + Cl -> ClO + O2) -Chlorine monoxide reacts with free oxygen atom which produces free chlorine again (ClO + O -> Cl + O2) -it aids in a reaction but doesn't get used up itself; single chlorine can catalyze up to 100,000 ozone before finding another chlorine atom,stopping the process -ozone molecules are not available to absorb incoming UV-B radiation, so it reaches Earth's surface, causing harm to biological organisms

Where does particulate matter come from? It is most commonly known as a class of pollutants released from combustion of fuels like...? Important sources of particulate matter? Do diesel powered vehicles or gasoline powered vehicles give off more particulate matter?

-combustion of wood, animal manure, and other biofuels, coal, oil, gasoline; road dust, rock crushing operations -coal, oil -volcanoes, forest fires, dust storms -diesel

When is carbon dioxide formed? Is the process that forms carbon dioxide more desirable or carbon monoxide? However, what has burning fossil fuels and subsequent production of carbon dioxide done to the atmosphere? What is the appearance of carbon dioxide?

-complete combustion of most matter, including fossil fuels and biomass -carbon dioxide -becoming a major pollutant, recently exceeded a concentration of 410 ppm in atmosphere and steadily increasing each year -colorless and odorless gas

Temperature also influences air pollution conditions in more complex ways. Normally, temperature ____________ as altitude _____________. Where is the warmest air and what direction does it travel? What does it bring with it? What does this allow to occur to pollutants at the surface? However, what occurs during a thermal inversion? What effect does it have on emissions?

-decreases, increases -closest to earth, rises into upper atmosphere -pollutants -reduced or diluted by the atmosphere above -relatively warm layer of air at mid altitude covers a layer of cold dense air below it, the warm layer is trapped, and since the air closest to surace of Earth is denser than air above it, cold air and pollutants do not rise -emissions are trapped beneath it, leading to a severe pollution event

Because solar radiation provides most energy for transformation from primary to secondary pollutants and since water is usually involved, when does conversion to secondary pollutants occur most rapidly?Example of secondary pollutnat? How is it formed? Are the main components of acid deposition also secondary pollutants?

-during the day and in wet environments -Ozone -formed in atmosphere as a result of emission of primary air pollutants NOx and VOCs in presence of sunlight -yes

In addition to human health problems, particulate matter and photochemical oxidants can also cause? How?

-economic harm -poor visibility in popular vacation destinations can reduce tourism revenues for recreation areas, such as for hotels and restaurants

Cause of the antarctic ozone hole:

-extremely cold weather conditions in winter cause buildup of ice crystals mixed with nitrogen oxide -Cl2 accumulates there as atmospheric chlorien interacts with ice crystals -When sun reappears in spring, UV radiation breaks this molecule down into Cl again, catalyzing destruction of ozone -Almost no ozone forms in dark of polar winter so a lot of thinning occurs -thinning diminishes as temperatures warm up and chlorine gets diluted by air coming from outside the polar region

Pollution control devices: fabric filters

-filtration device that allows gases to pass through them but remove particulate matter -can remove almost 100% of particulate matter emissions -often called baghouse filters

Volative Organic compounds are used in building materials, furniture, and other home products such as...? Most toxic of these? Where is it used? Over time, what does it do? What toxic effects does it have on humans? What can be done to prevent household exposure to VOCs?

-glue, paints -formaldehyde -building products like particle board and carpeting glue, common in new homes and new manufactured artificial woods (think hardwood floors, bookcases) -emits gases over time and is volatile -high concentration in enclosed space has burning sensation in eyes and throat, breathing difficulties/asthma in some people, possibly a carcinogen, people develop sensitivity to it -utilizing wood flooring rather than carpeting or natural fiber carpeting rather than synthetics

Where does stratospheric ozone occur (making its function different from tropospheric ozone)? When solar radiation strikes O2 in the atmosphere, 16-50 km above Earth's surface, a series of chemical reactions begin, producing which new molecule? In the first step, what does UV-C do? Does this happen to a lot of oxygen molecules at a given time? What occurs in the second step? How does the ozone break back down again? This process can occur indefinitely, as long as...?

-higher in the atmosphere, making its function critical to Earth, since it can shield UV rays -ozone! -breaks molecular bond holding oxygen molecule together (O2 + UV-C -> O + O) -no, the vast majority of oxygen in atmosphere remains O2 -free oxygen atom produced in first reaction encounters oxygen molecule and they form ozone: (O + O2 -> O3) -UV-B and UV-C radiations breaks a bond -there is enough UV energy entering the atmosphere (at normal levels this remains at a steady state)

In the US, acid deposition increased substantially from 1940s through 1990s as a result of..? What did it have effects on? Effects of acid deposition can be _________ or ____________ and it is often difficult to determine this, making remediation difficult. The greatest effects of acid deposition have been on what ecosystems? Why has lower pH of lakes and streams in scandinavia, North America , and UK caused decreased species diversity of aquatic organisms?

-human activity -materials, agricultural lands, and aquatic and terrestrial natural habitats -indirect, direct -aquatic ecosystems -many species can only survive in a narrow range of environmental conditions (ex: amphibians will survive when pH of lake is 6.5 but when it acidifies to pH 6.0 or 5.5, same organism will experience developmental or reproductive problems

The Clean Air Act and various amendments require that the EPA establish standards to control pollutants that are harmful to ___________ _____________ _______ ______________. What does the term human health mean? Welfare? What act does the EPA periodically set concentration limits for each pollutant through?

-human health and welfare -health of human population and includes elderly, children and sensitive populations -visibility, status of crops, natural vegetation, animals, ecosystems, buildings -National Ambient Air Quality Standards (NAAQS)

Examples of VOCs? Another interesting characteristic of most VOCs (think smell)? VOCs play an important role in the formation of what? Why are they not considered to be air pollutants?

-hydrocarbons (compounds containing carbon hydrogen bonds) such as gasoline, lighter fluid, and perfumes -compounds that give off strong aroma are often VOCs since chemicals are easily released into the air -photochemical oxidants such as ozone -they are not particularly harmful (like VOCs given off by conifer trees) but can lead to formation of photochemical oxidants and therefore have potential to be harmful

When is carbon monoxide formed? Where is it a significant source of air pollution? What is its appearance like? How is it a big problem in developing countries?

-incomplete combustion of most matter (therefore common pollutant in vehicle exhaust and most other combustion processes) -urban areas, indoor air pollutant when exhaust systems on natural gas heaters malfunciton -people cook with manure, charcoal, or kerosene within poorly ventilated structures

Although it receives less attention than outdoor air pollution, ____________ air pollution also has devastating effects. The reasons for this differ between what two groups?

-indoor -developing and developed countries

Is carbon monoxide more dangerous inside or outside? Why does it occur indoors? Why is it especially problematic if inhabitants of house are asleep? What does extended exposure to carbon monoxide lead to in humans? What do we have to help prevent this?

-inside -malfunctioning exhaust systems (exhaust air escapes into living space, and colorless, odorless carbon monoxide accumulates in house without inhabitants noticing) -they will not notice -oxygen deprivation in brain and ultimately, death -carbon monoxide detectors!

What was asbestos used for in houses for many years? Greatest health risks from it? In manufactured form, it is relatively stable; when does it become harmful? Is it still used in the US? Why does asbestos removal have to be carefully done by a qualified asbestos abatement personnel?

-insulator on steam and hot water pipes and in shingles for insulation of buildings -respiratory diseases like asbestosis and lung cancer -when it is disturbed -no, but remains in older buildings (like schools) -it has to be done under very tightly controlled conditions as to not disrupt or disturb asbestos

How can particulate matter affect rates of photosynthesis? What is this called? Is particulate matter the only pollutant that can do this?

-it scatters and absorbs light; if atmospheric concentrations are high enough, incoming radiation would be reduced enough to affect photosynthesis -haze -no, ozone and photochemical oxidants also play important indirect role in formation of haze

Acid deposition has been reduced in the US as a result of? What major international borders does acid deposition cross in order to be deposited in another region? Can precursors to acid deposition emitted in one region have a significant impact in another region or in another country? Example?

-lowered sulfur dioxide and nitrogen oxide emissions due to Clean Air Act Amendments passed in 1990 -between US and canada, and carried from England, Germany, and Netherlands to Scandinavia -yes -legislative/legal attempts to restrict emissions in midwestern US falling as acid deposition in Canada and have largely worked, however recently observed acid deposition on west coast of US is believed to be a result of coal combustion in China

Lower pH can lead to mobilization of ________ as an indirect effect. When this happens, metals bound to organic or inorganic compounds in soils or sediments are released where? Why can exposure to aquatic organisms of these metals lead to species loss? What else can decreased pH affect relating to aquatic organisms? Are organisms on land also impacted similarly?

-metals -into surface water -they can impair physiological functioning of aquatic organisms -affect food sources of aquatic organisms -yes

When did atmospheric researchers begin to notice that the stratospheric ozone in Antarctica had been decreasing each year? Since late 1970s, global ozone concentrations have been decreasing by what percent? Where is depletion greatest?

-mid 1980s -more than 10% -at the poles, but occurs worldwide

In contrast to natural emissions, emissions from human activity are _____________, ______________, and in many cases, ________________. The EPA reports periodically on emission sources of the criteria air pollutants for entire US, listing pollution sources in categories like..? What category is the largest source of carbon monoxide and nitrogen oxide? Major source of anthropogenic sulfur dioxide? What sources does particulate matter come from?

-monitored, regulated, controlled -on road vehicles, power plants, industrial processes, waste disposal -transportation -electricity generation and other stationary source fuel combustion -variety of sources including natural and human made fires, agriculture, road dust, and generation of electricity

How many US americans have been exposed to air that did not comply with the maximum allowable ozone concentrations? Which of the six pollutants have researchers had most difficulty with controlling? Why are these so difficult to regulate?

-more than 4 in 10 (as of 2017) -photochemical smog and ozone -chemistry of smog formation and behavior of atmosphere during changing weather conditions, making smog formation very complex and difficult to predict and reduce

How does sick building syndrome occur? For what types of buildings is it particularly common?

-new buildings contain many products containing synthetic materials, significant amount of off gassing occurs which means indoor levels of VOCs, hydrocarbons, and other potentially toxic materials are quite high -office buildings where workers have complained of maladies like headaches, nausea, etc

Second part of process to create photochemical smog (few VOCs): A few hours later, when sunlight intensity decreases and nitrogen oxide is still present in the n=atmosphere, ozone combines with..... to form...? What is this referred to? Is this a natural process and when does this occur? When volatile organic compounds are absent or in small supply, what is the cycle of ozone formation and destruction like?

-nitrogen oxide (NO); O2 + NO2 -ozone destruction -natural process that happens in latter part of day or evening -takes place on daily basis and relatively small amounts of photochemical smog occur

How Acid Deposition Forms: What is released into the atmosphere through natural and anthropogenic combustion processes? What secondary pollutants are they then transformed into? Through the presence of what? These secondary pollutants then break down further, producing which inorganic nutrients and what ion that generates teh acidity of acid deposition? How long does it take for this transformation to occur? How far can pollutants travel in this time? Eventually, the secondary acidifying pollutants are washed out of the air and deposited where?

-nitrogen oxides (NO and NO2) and sulfur dioxide (SO2) -nitric acid (HNO3) and sulfuric acid (H2SO4) -nitrate, sulfate; hydrogen ions -number of days - a thousand kilometers (600 miles) or more -washed out of air and deposited as precipitation or in dry form on vegetation, soil, or water

In the presence of __________ and ___________ oxides, photochemical oxidants can enhance the formation of certain ______________ matter, which contributes to _____________ ________. What is the resulting mixture called? Two categories of smog? What type of compounds is each type of smog dominated by?

-nitrogen, sulfur, particulate, scattering light -smog -photochemical smog (oxidants like ozone) , sulfurous smog (sulfur dioxide or sulfate compounds)

Why is indoor air pollution from carbon monoxide and particulates a particular hazard in developing countries? Exposure to indoor air pollution from cooking and heating increases risk of what? What percent of deaths attributable to indoor air pollution occur in developing countries?

-no exhaust system and little or no ventilation available in the home -acute respiratory infections, pneumonia, bronchitis, even cancer -90%

Although smog is associated with urban areas, is it limited to such areas? Several important ways that atmospheric temperature influences formation of smog?

-no, can occur in residential areas as a result of trees and shrubs as well as forest fires -1. emissions of VOCs from vegetation and evaporation of volatile liquids like gasoline increase as temp increases 2. NOx emissions from fuel combustion by electric utilities are greater with air conditioning demands for electricity increasing on hottest days 3. many chemical reactions forming ozone and other photochemical oxidants proceed more rapidly at higher temps

Are humans harmed by direct contact with acid deposition? What harms them more?

-no, human skin is a sufficient barrier -precursors to acid deposition like sulfur dioxide and nitrogen oxides

Is the formation of photochemical smog well understood? A number of pollutants are involved and they undergo a series of complex transformations in the atmosphere including..?

-no, it is very complex -sunlight, water, presence of VOCs

A variety of different pollution control devices remove ____________ _________ and sometimes other compounds after combustion. Each has its advantages and disadvantages and all of them use __________ - most commonly _________________- which generates additional pollution. Three major types of pollution control devices? Why do all three methods result in increased carbon dioxide emissions and require more fuel?

-particulate matter, energy, electricity -Fabric filters/ baghouse filters; electrostatic precipitators; scrubber -because they use additional energy and increase resistance to air flow in factory or powerplant

In many parts of Asia, air quality has been so severely impaired by _____________ ___________ and ____________ that visibility has been reduced, in some cases by more than ____%. What cities tend to dominate NGO and environment organization's lists of most polluted cities in the world?

-particulate matter, sulfates, 20 -Chinese and Indian cities, but in 2017 Zabol Iran first appeared as one of most polluted cities

What are photochemical oxidants harmful to? However, it is normally not the focus of environmental scientists; what is? Is this harmful to both plants and animals? How does it harm them?

-plant tissue, human respiratory tissue, construction materials -ozone -yes -impairs respiratory function

What does the term air pollution typically refer to? Two ways in which it can occur? Why is air pollution a global system? Inputs into the system? Outputs?

-pollution in troposphere (also called ground level pollution) -natural or anthropogenic sources -atmosphere envelops the whole globe and one of the major repositories for air pollutants is the atmosphere -sources of pollution -components of atmosphere and biosphere that remove air pollutants

What is the overall global trend in the decrease of stratospheric ozone concentration due to? Decreased stratospheric oxygen has led to an increase in the amoutn of what that reaches earth? Since 1992, have radiation levels in North America risen? How can increased exposure affect plants and humans?

-presence of chlorofluorocarbons (and chlorine) -UV B radiation -no, remained constant -reduces photosynthetic activity of plants which could affect ecosystem productivity -in humans, mainly lighter skins, it could correlate with increased risk of skin cancer, cataracts, and other eye problems, and with suppressed immune system

The first portion of the process that creates photochemical smog occurs during the..? When an abundance of nitrogen oxides are present and very few VOCs present, what does nitrogen dioxide split to? In presence of energy inputs from sunlight, what does this then turn into? So.. when does ozone accumulate in the atmosphere?

-presence of sunlight -nitrogen oxide (NO) and free oxygen atom (O) -combines with diatomic oxygen (O2) to form ozone (O3) -with abundant nitrogen dioxide and abundant sunlight

Is preventing pollution or controlling it less expensive? Best way to decrease air pollution emissions? How can this be achieved? Why can using low sulfur coal or oil be difficult to do? Other ways to reduce air pollution include..? Since preventing pollution is so difficult, what do most attempts to reduce air pollution depend on?

-preventing pollution -avoid them in the first place -using coal and oil with lower sulfur concentration, reducing concentration of sulfur through refining and processing -increased efficiency and conservation (however, pollution will still be emitted whenever fuel is combusted) -depends on control of pollutants after combustion

Because main component of photochemical smog is ozone (secondary pollutant) what must efforts to reduce smog be directed at? Historically, most local smog reduction measures have been directed at? What have more recent regional efforts to control ozone focused on? This has proven to be a more effective way to control smog in areas away from ___________ _____________.

-primary pollutants -reducing emissions of VOCs in urban areas (with fewer VOCs in air, fewer compounds to interact with nitrogen oxides so more nitrogen oxide will be available to recombine with ozone) -reducing nitrogen oxide emissions -urban centers

When trying to control secondary pollutants, what is important to consider? Is human activity the only source of air pollutants? What are some examples of pollution that do not come from humans?

-primary pollutants that created them, factors that can lead to formation, breakdown, or reduction in secondary pollutants themselves -no -volcanoes, lightning, forest fires, and plants both living and dead

What does ozone act as in the stratosphere?The sun radiates energy at many different wavelengths including the _____________ range. Three groups of ultraviolet wavelengths? UV radiation of all types can damage what? How does exposure to UV B harm humans, plants, and communities in general?

-protective shield against radiation from the sun -ultraviolet -UV-A (low energy UV radiation), and UV-B and UV-C (shorter, high energy wavelengths) -tissues and DNA of living organisms -increases risk of skin cancer and cataracts and suppresses immune system of humans; harmful to cells of plants and reduces ability to carry out photosynthesis -harm entire biological communities

One of the most innovative aspects of the Clean Air Act? A power plant can emit how much sulfur dioxide annually with a sulfur allowance? How are sulfur allowances given out? What occurs to facilities who emit more than their allowances?

-provision for buying and selling of allowances authorizing the owner to release certain quantity of sulfur -one ton -awarded annually to existing sulfur emitters proportional to amounts they were emitting before 1990 and emitters not allowed to emit more than amount they have permits for -must pay financial penalty

Is the atmosphere a public or private resource? Six pollutants the original US Clean Air Act of 1970 that significantly threaten human well being, ecosystems, and structures? What were these called and why? What is one important pollutant not included in this?

-public, so science of air pollution is closely intertwined with political and social perspectives -sulfur dioxide, nitrogen oxides, carbon monoxide, particulate matter, tropospheric ozone, and lead -criteria air pollutants because EPA must specify allowable concentrations of each pollutant -carbon dioxide

Each year, the EPA issues a report that shows the national level of the six criteria air pollution standards relative to the _____________ ____________. Over the last two decades have all criteria air pollutants increased or decreased in the US? In the last few years, which two concentrations have been close to or above the NAAQS? Which one has decreased most significantly?

-published standards -decreased -ozone and lead -lead (since it is no longer added to gasoline)

What is Radon-222? Where does it exist in terms of indoor pollutants? How do humans become exposed? It decays within 4 days to radioactive daughter product, which is? How do they become inhaled by humans?

-radioactive gas that occurs naturally from decay of radium -exists in granitic and some other rocks and soils in many parts of the world -polonium-210 -radon or polonium can attach to dust or other air particles and then be inhaled by inhabitants

Most common means of pollution control? The process of removing this also removes sulfur. Simplest method to remove particulate matter is? How does it work? Depending on the fuel that was burned, the ask may contain sufficiently high concentrations of what that may require special disposal?

-removal of particulate matter -gravitational settling, relies on gravity as exhaust travels through the smokestack -particles settle to bottom and ash residue that accumulates must be disposed of in a landfill -metals

Pollution control devices: electrostatic precipitators

-remove particulate matter by using an electrical charge to make particles coalesce so they can be removed -polluted air enters precipitator and electrically charged particles are attracted to negative positive charges on sides of precipitator, particles collect and relatively clean gas exits precipitator -helped reduce pollution significantly before it is released into atmosphere, when it is harder to collect

How does sulfur dioxide damage organisms? How is it formed/ when is sulfur dioxide released?

-respiratory irritant, and can adversely affect plant tissue -when fossil fuels combust when they contain sulfur, which later combines with oxygen to form sulfur dioxide -Volcanic eruptions and forest fires

In the antarctic, ozone depletion is _____________, which season has greatest depletion? What is the lack of ozone over antarctica called? Does this also occur in the arctic?

-seasonal -roughly August through November -ozone hole -yes, but less extreme from January through April

Long before anthropogenic pollution, what did the natural VOCs from plants give rise to? What other areas can also give rise to air pollution related to human activity on land? What major event demonstrates this? Across the globe a large percentage of air pollution is __________, but in Northern America, as much as _______% of pollution (from nitrogen oxides and sulfur dioxide) is due to anthropogenic causes. What do the effects of compounds from natural emissions depend on?

-smog and photochemical oxidant pollution -large nonindustrial areas like agricultural fields give off particulate matter when plowed -Dust Bowl of 1930s -natural, 95 -in part on natural conditions, such as wind direction

Thermal inversions that create pollution events are particularly common where? What other kinds of pollution can thermal inversions lead to? Example?

-some cities where high concentrations of vehicle exhaust and industrial emissions are easily trapped by the inversion layer -carbon monoxide and particulate matter from coal used in stoves during a cold spell occurring after Tianjin (chinese city) shut off district heating system for the season

Acid deposition can harm human built structures like what? How does it harm them? When the hydrogen ion from acid deposition interacts with limestone or marble, what does the calcium carbonate do?In the process what occurs to the calcium carbonate material? Will increasing acidity of deposition cause increasing damage? What other forms of acid deposition can contribute to to decay of structures?

-statues, monuments, buildings -acid deposition reacts with building materials -reacts with H+ and gives off Ca ^2+ -calcium carbonate material is partially dissolved -yes -gaseous sulfur dioxide or sulfuric acid vapor

Common air pollutants in the US include? What occurs during the process to reduce sulfur dioxide emissions known as fluidized bed combustion? What can sulfur dioxide that escapes combustion process be captured by?

-sulfur and nitrogen oxides -granulated coal is burned in close proximity to calcium carbonate, heated calcium carbonate absorbs sulfur dioxide and produces calcium sulfate which can be used for sheetrock for houses -other methods after combustion

A number of cities around the world (Including what?) have taken ____________ and often _____________ measures to reduce smog levels? Examples that municipialities have passed? (at least 3 name)

-those in China, Mexico, and England -innovative, controversial -1. reduce amount of gasoline spilled at gas stations 2. restrict evaporation of dry cleaning fluids 3. restrict use of lighter fluid (a VOC) for starting charcoal barbecues 4. Urban and suburban areas have taken additional actions like calling for reduction in wood burn stoves or fireplaces reducing emissions of many pollutants 5. California municipalities suggested reducing number of bakeries in areas, since rising bread produces VOCs (however, emissions from bakeries/local businesses regulated by local air quality ordinances)

Lead also occurs in lead based paint in older buildings, what effect does this have for adults or children? What is another metal that is also found in coal and oil and has effects on humans similar to lead? Is it regulated by the EPA? Why have their concentrations increased rapidly over the past few years? What will likely be the focus of future regulations?

-toxic to CNS and affect learning and intelligence, mainly for young children who could by attracted by sweet taste -mercury -yes, in the hazardous air pollutants program -release of mercury into air and water from combustions of fossil fuels, concentrations in fish have also increased -emissions standards for coal plants since coal fired electricity generation remains the largest uncontrolled source of mercury

What is lead? Is it present in fuels like oil and coal? What occurred during the time hat lead compounds were added to gasoline to improve vehicle performance? When was lead phased out as a gasoline additive in the US? Did this decrease its concentration in global air? Has the removal of lead in gasoline occurred globally?

-trace metal that occurs naturally in rocks and soils -yes, in small concentrations -lead compounds released into air traveled with prevailing winds and were deposited on the ground by precipitation, and became pervasive around the globe, including polar regions far from the source -between 1975 and 1996 - yes -no, but a campaign is still underway

Pollution Control Devices: Scrubber

-uses combo of water and air that actually separates and removes particles -particles are removed in a liquid or sludge form and clean gas exits -particles sometimes iodized to increase scrubbers efficiency -also remove sulfur dioxide -help reduce pollution significantly before it is released into atmosphere, when it is harder to collect

Smog formation is different when high amounts of VOCs are present... Does the first part remain the same? How do high amounts of VOCs affect ozone destruction? How does this impact the amount of ozone in the atmosphere? This occurs with an abundance of VOCs and..... primarily in which kind of areas?

-yes -VOCs combine with nitrogen oxide (NO) in a strong bond, making nitrogen oxide no longer able to bond with ozone -since NO is not available to break down ozone by bonding with it, larger amount of ozone accumulates -nitrogen dioxide, daytime accumulation of ozone in urban areas

Can sulfur allowances be bought or sold on open market by anybody? Over time has the amount of sulfur allowances increased or decreased? Overall economic cost for achieving these reductions has been more or less than original cost estimate? Global change researchers have used sulfur allowance example as a model for more recent experiments with buying/ selling...?

-yes -decreased, number of allowances each year has been gradually reduced -less, 1/4 less -carbon dioxide allowances

Four specific reasons for sick house syndrome identified by EPA?

1. inadequate or faulty ventilation 2. chemical contamination from indoor sources like glues, carpeting, furniture, etc 3. chemical contamination in building from outdoor sources like vehicle exhaust transferred through building air intakes 4. biological contamination from inside or outside, like molds, or pollen

Factors that have caused quality of air in homes to take a greater importance in recent decades?

1. people in developed world have begun to spend more time indoors 2. tightly sealed buildings reduce energy consumption, but keep existing air in contact with inhabitants of building for longer periods of time 3. increasing number of materials in home/office made of plastics/ other petroleum based materials that can give off chemical vapors

How do each of the following contribute to pollution: volcanoes, lightning, forest fires, and living plants

1. releases sulfur dioxide, particulate matter, carbon monoxide, nitrogen oxides 2. create nitrogen oxides from atmospheric nitrogen 3. release particulate matter, nitrogen oxides and carbon monoxide 4. release a variety of VOCs, and smell from citrus fruits and conifer trees are mostly due to turpenes, which can be precursors to photochemical smog

Asbestos

A long, thin, fibrous silicate mineral with insulating properties, which can cause cancer when inhaled.

Secondary pollutant

A primary pollutant that has undergone transformation in the presence of sunlight, water, oxygen, or other compounds

thermal inversion

A situation in which a relatively warm layer of air at mid-altitude covers a layer of cold, dense air below.

smog

A type of air pollution that is a mixture of oxidants and particulate matter

Sulfur Dioxide (SO2)

Air pollution Formed when fossil fuels, which contain sulfur, are burned Has the ability to dissolve in water vapor to form sulfuric acid and interact with the particulate matter and gases in the air to form other products Primary Pollution

Volatile Organic Compounds (VOCs)

An organic compound that evaporates at typical atmospheric temperatures.

Sulfurous smog

Dominated by sulfur dioxide and sulfate compounds. Also known as London type or gray smog.

Equation for natural ozone accumulation (from natural and anthropogenic sources)

NO2 -> NO + O -> O + O2 -> O3

Equation for natural ozone destruction

O3 + NO -> O2 + NO2

haze

Reduced visibility

Photochemical smog

Smog that is dominated by oxidants such as ozone. Also known as Los Angeles-type smog; Brown smog.

Particulate matter (PM)

Solid or liquid particles suspended in air; also known as particles and particulates.

sick building syndrome

a buildup of toxic pollutants in an airtight space, seen in newer buildings

Photochemical oxidant

a class of air pollutants formed as a result of sunlight acting on compounds such as nitrogen oxides

primary pollutants

a polluting compound that comes directly out of a smokestack, exhaust pipe, or natural emission source

What are most common indoor air pollutants?

carbon monoxide, asbestos, radon, VOCs in home products

Depending on the source, air pollutants can be classified as...?

primary or secondary pollutants

Air Pollution

the introduction of chemicals, particulate matter, or microorganisms into the atmosphere at concentrations high enough to harm plants, animals, and materials such as buildings, or to alter ecosystems

inversion layer

the layer of warm air that traps emissions in a thermal inversion