Post on 26-Dec-2015
Air Pollution
By Andrew Kielar andBrannock Furey
Layers of the Atmosphere Atmosphere Divided into
several layers Troposphere Stratosphere Mesophere Thermosphere
Many sharp differences occur across layers
Troposphere
Layer closest to the surface
Very thin Majority of air
mass located here Recycles nutrients
Stratosphere
Second layer About 2.5 times as
big as the troposphere
Works as a “sunblock” for the Earth
Contains the O-zone layer and also has the highest concentration of O-zone(O3)
2 Types of Pollution Sources Air pollution Air pollution
comes from either natural or human sources
Natural Pollution Human Pollution
History of Air Pollution
Industrial Revolution
London United States Health Effects
Hybrid Pollutants
2 types of pollutants Primary Secondary
Effects of winds Good News Bad News Indoor Air Pollution
Indoor Air Pollutants
Carbon Oxides Nitrogen Oxides
and Nitric Acid Sulfur Dioxide and
Sulfuric Acid Patriculates O-Zone VOCs
Lead
Does not break down in the Environment
Fairly common negative effects America
Effect on Children is steadily decreasing
Burning Coal
Cities that commonly burned coal were subject to industrial smog
Coal is commonly used to produced electricity
Currently, risk of smog is cut down because of safer and more regulated burning practices
Photochemical Smog
Photochemical Reaction
Photochemical Smog
Influences of weather on Photochemical smog
Effect on modern cities
Variables of Air Pollution
Increase Urban Buildings Hills and Mountains High Temperatures Natural VOCs Grasshopper Effect Temperature
Inversions
Decrease Gravity Precipitation Salty Ocean Air Winds Chemical Reactions
Acid Deposition
Pollution from smokestacks
Pollutants Acid deposition Largest acid
releases in Midwest
International Acid deposition
Harmful Effects
Human Respiratory diseases
Damages human-made structures
Pollute water Harm aquatic
ecosystems Affect plant life
and vegetation
Indoor Air Pollution
Developing countries: indoor burning of wood, charcoal, dung, crop residues, and coal exposes people to dangerous levels of air pollution
WHO and World Bank: indoor air pollution is, for poor people, the world’s most serious air pollution problem
Developed countries – Typical sources of indoor air pollution: asbestos, carbon monoxide, Radon-222, formaldehyde, etc.
EPA Studies: (1) levels of 11 common pollutants generally 2 – 5 times higher inside U.S. homes and commercial buildings than outside, (2) pollution levels inside cars in urban areas can be up to 18 times higher than outside levels, and (3) health risk from exposure to such chemicals magnified because people in developed countries spend most of their time indoors.
Indoor Air Pollution
Living organisms and their extrements – dust mites and cockroach droppings – important role in almost threefold increase of asthma in the U.S.
Airborne spores of molds and mildew Sick-building syndrome => Almost 1 in 5 commercial
building in the U.S. is considered “sick” Four most dangerous indoor air pollutants: tobacco
smoke, formaldehyde, radioactive radon-222 gas, and very small particles
Formaldehyde => people exposed have a 34% higher than normal risk of getting Lou Gehrig’s disease
Indoor Air Pollution – Radioactive Radon Gas
Radon-222: concentrated in underground mineral deposits. In buildings above these deposits, radon gas can seep in, build up to high levels, and decay into solid particles of other radioactive elements. Inhalation of these over long period of time => lung cancer
Health Effects of Air Pollution Body’s numerous defenses in respiratory system – nasal
hairs, sneezing and coughing, cilia – can be overwhelmed by prolonged or acute exposure to air pollutants. Can lead to: asthma, chronic bronchitis, emphysema
WHO: at least 3 million people worldwide die prematurely each year from the effects of air pollution
In the U.S., EPA estimates that 150,000 – 350,000 annual deaths are related to indoor and outdoor pollution
EPA: each year, more than 125,000 Americans get cancer from breathing soot-laden diesel fumes from buses and trucks Proposed stricter emission standards
2007 study: emissions from ocean-going ships are responsible for 60,000 premature deaths each year worldwide
Laws and Regulations for Air Pollution
Congress passed Clean Air Acts in 1970, 1977, 1990: established air pollution regulations
EPA directed to establish “national ambient air quality standards” for six outdoor “criteria pollutants”: carbon monoxide, nitrogen oxides, sulfur dioxide, suspended particulate matter, ozone, and lead.
EPA has established national emission standards for more than 188 “hazardous air pollutants”
“Toxic Release Inventory” (TRI) requires 21,500 refineries, power plants, mines, and factories to report their releases and waste management for 667 toxic chemicals.
2007 EPA report: combined emmissions of the six major air pollutants decreased 49% between 1980 and 2006.
Arrival of low-sulfur diesel fuel => push for new generation of diesel engines
U.S. Air Pollution Laws Can be Improved
Environmental scientists point to the following deficiencies of U.S. air pollution laws: The U.S. continues to rely mostly on pollution cleanup rather than
prevention For decades, the US. Congress failed to increase fuel-efficiency
standards for cars, SUVS, and light trucks. Regulation of emissions from motorcycles and two-cycle gasoline
engines remains inadequate. There is little or no regulation of air pollution from oceangoing ships
in American ports. Airports are exempt from many air pollution regulations. The laws do not regulate emissions of the greenhouse gas CO2
Ultrafine particles are not regulated. Urban ozone levels are still too high in many areas. The laws have failed to deal seriously with indoor air pollution. There is no need for better enforcement of the Clean Air Acts.
The Marketplace Can Help Reduce Outdoor Air Pollution
Clean Air Act of 1990: for SO2 – an “emissions trading”, or “cap-and-trade program” which enables the 110 most pollution power plants
Proponents: Cheaper and more efficient than government-run program
Critics: Allows dirtier, older plants to keep polluting Between 1990 and 2006, the emissions trading
system helped to reduce SO2 emissions from electric power plants in the United States by 53% at a cost of less than 1/10 the cost projected by industry.
Ways to Reduce Outdoor Pollution
Stationary Source Air Pollution: Prevention: Burn low-sulfur coal, Remove sulfur from coal,
Convert coal to a liquid or gaseous fuel, Shift to less polluting energy source
Dispersion or Cleanup: Disperse emissions above thermal inversion layer with tall smokestacks, Remove pollutants after combustion, Tax each unit of pollution produced
Motor Vehicle Air Pollution Prevention: Use mass transit, Walk or bike, Use less pollution
fuels, Improve fuel efficiency, Get older, polluting cars off the road, Give large tax write-offs or rebates for buying low-polluting, energy-efficient vehicles
Cleanup: Require emission control devices, Inspect car exhaust systems twice a year, Set strict emission standards
Reducing Indoor Air Pollution Prevention
Clean ceiling tiles and line AC ducts to prevent release of mineral fibers
Ban smoking or limit it to well-ventilated areas Set stricter formaldehyde emissions standards Prevent radon infiltration Use office machines in well ventilated areas Use less polluting substitutes for harmful cleaning angents, paints,
and other products Cleanup or Dispersion:
Use adjustable air vents for work spaces Increase intake of outside air Change air more frequently Circulate a building’s air through rooftop greehouses Use efficient venting systems for wood-burning stoves Use exhaust hoods for stoves and appliances burning natural gas
Reducing Air Pollution
Outdoor Improve energy efficiency to reduce fossil fuel use Rely more on lower-polluting natural gas Rely more on renewable energy Transfer energy efficiency, renewable energy, and pollution
prevention technologies to developing countries Indoor
Reduce poverty Distribute cheap and efficient cook stoves or solar cookers to
poor families in developing countries Reduce or ban indoor smoking Develop simple and cheap tests for indoor pollutants such as
particulates, radon, and formaldehyde