Air Pollution

SOURCES of pollution an analogy Point sources Non-point sources Easy to point out : Hard to point at just one

Point Sources Like giants big easy to spot e.g. factories e.g. power plants

Example of a point source (There it is!)

Examples of non-point sources (Where?—All over.)

What are non-point sources? Like ants small all over the place, often moving so many of them it is hard to POINT OUT all of them e.g. cars e.g. houses e.g. construction sites e.g. farms e.g. fires

air pollutants—Most result from burning fuels excess carbon dioxide: CO2 ----sooo much more than natural Ozone: ground level O3 (the bad ozone) in urban smog; destroys our lungs; ozone alert days in summer (but our lives depend on good ozone way up in the stratosphere!) Carbon monoxide: CO reduces blood’s ability to carry O2 product of incomplete combustion (bad old cars) Nitrogen oxides: NOx Sulfur Dioxide: SO2 precursor to acid rain along with NOx Particulate Matter respiratory disorders Source: http://www.epa.gov/oar/oaqps/greenbk/o3co.html#Ozone Nitrogen dioxide (NO2) is a brownish, highly reactive gas that is present in all urban atmospheres. NO2 can irritate the lungs, cause bronchitis and pneumonia, and lower resistance to respiratory infections. Nitrogen oxides are an important precursor both to ozone (O3) and acid rain, and may affect both terrestrial and aquatic ecosystems. The major mechanism for the formation of NO2 in the atmosphere is the oxidation of the primary air pollutant nitric oxide (NO). NOx plays a major role, together with VOCs, in the atmospheric reactions that produce O3. NOx forms when fuel is burned at high temperatures. The two major emissions sources are transportation and stationary fuel combustion sources such as electric utility and industrial boilers. Ozone (O3) is a photochemical oxidant and the major component of smog. While O3 in the upper atmosphere is beneficial to life by shielding the earth from harmful ultraviolet radiation from the sun, high concentrations of O3 at ground level are a major health and environmental concern. O3 is not emitted directly into the air but is formed through complex chemical reactions between precursor emissions of volatile organic compounds (VOC) and oxides of nitrogen (NOx) in the presence of sunlight. These reactions are stimulated by sunlight and temperature so that peak O3 levels occur typically during the warmer times of the year. Both VOCs and NOx are emitted by transportation and industrial sources. VOCs are emitted from sources as diverse as autos, chemical manufacturing, dry cleaners, paint shops and other sources using solvents. The reactivity of O3 causes health problems because it damages lung tissue, reduces lung function and sensitizes the lungs to other irritants. Carbon monoxide (CO) is a colorless, odorless and poisonous gas produced by incomplete burning of carbon in fuels. When CO enters the bloodstream, it reduces the delivery of oxygen to the body's organs and tissues. Health threats are most serious for those who suffer from cardiovascular disease, particularly those with angina or peripheral vascular disease. Exposure to elevated CO levels can cause impairment of visual perception, manual dexterity, learning ability and performance of complex tasks. 77% of the nationwide CO emissions are from transportation sources. Center for Sustainable Systems Final Report on DaimlerChrysler Corp Fund Grant #8517.03

CFCs—a success story? –maybe Chlorofluorocarbons (CFCs) --an unreactive gas, seemed perfect as propellant plastic foam refrigerator equipment (old) old spray cans Eventually reached the ozone layer destroyed good ozone --- ozone in the stratosphere. Banned several years ago too late? Is too much damage done? the replacement chemicals—Are they ok?

Natural Air Pollutants Natural air pollutants can include: Smoke from wild fires Volcanic eruptions Methane released from livestock not here here! here!

Consequences of Air Pollution decreased quality of life! breathing sicknesses (asthma, emphysema) acid rain increased greenhouse effect, which leads to GLOBAL WARMING

How is the greenhouse effect related to global warming? The Greenhouse Effect– a natural process, greatly exaggerated by us humans How is the greenhouse effect related to global warming?

Acid Rain: Its effect on trees A smoggy city

WAYS TO reduce AIR POLLUTION and global warming Everyone pollutes. You can’t stop it, but you can reduce it. What can you do? What are you willing to do? Some ideas: Transportation: Walk, ride a bike, use public transportation, use cars less, get a more energy-efficient car Buy only energy-efficient appliances Re-use materials Recycle newspaper, aluminum, others Plant trees in urban areas Don’t purchase products that contain CFCs Support much stricter clean air laws Support enforcement of international treaties to reduce ozone depletion and slow global warming Don’t buy so much stuff!

Air Pollution Guided Notes Answer these. Compare non-point sources and point sources of air pollution. 2. Give examples. 3. Which do you think cause worse problems in North Carolina? Why? Do giants and ants really pollute the air? Why are giants and ants referred to in the lesson on pollution? Name 7 air pollutants caused by humans and tell what each pollutant does. Name three air pollutants that are not caused by humans. How is the greenhouse effect related to global warming? Name ≥5 ways that you or your family could reduce air pollution. Be specific. Which ones are you willing to try?