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Air Pollution

Air Pollution. The atmosphere. Composition: 78% N2, 21% O2 and 1% CO2, other gases and water vapor Sources of natural air pollutants include volcanoes, forest fires, plants, and soil Sources of anthropogenic air pollutants include transportation, energy production, and industry. .

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Air Pollution

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  1. Air Pollution

  2. The atmosphere Composition: 78% N2, 21% O2 and 1% CO2, other gases and water vapor Sources of natural air pollutants include volcanoes, forest fires, plants, and soil Sources of anthropogenic air pollutants include transportation, energy production, and industry.

  3. Natural air pollution: volcanic activity

  4. Sources of air pollution for Puget Sound

  5. Criteria Air Pollutants

  6. Carbon monoxide (CO) produced from the incomplete combustion of organic materials (particularly fossil fuels). Sources: autos (62%), lawn equipment (10%), and forest fires (6%). CO does not persist, but is converted into non-harmful compounds. By mass, it is the most abundant air pollutant. Exposure to this gas can be fatal to humans

  7. Sulfur oxides from sulfur-containing fossil fuels primarily coal (used for the generation of electricity and industry). It forms SO3 and H2SO4 which contribute to acid deposition.

  8. Nitrous oxides (e.g., Nitrogen dioxide) from combustion that releases O2 which combines with N from the air. These also are the result of autos (~ 50%) and electrical utility and industrial combustion (most of the rest). These gases are components of smog, acid deposition, and also are components of harmful secondary pollutants.

  9. Ozone is good far up in the atmosphere, but trophospheric ozone is bad. It is a major component of smog, & can cause health problems especially for those who have compromised respiratory systems.

  10. Particulates (small pieces of solids e.g., ash, asbestos, dust etc.) Some are carcinogenic, others trap diverse “nasties” on their surfaces. London’s killer smog of 1952 (responsible for 4,000 deaths over 4 days) was partially the result of this type of pollutant (also from SO2).

  11. Lead was a problem prior to the change in gasoline (leaded to unleaded). Compounds containing lead where added to gasoline and then released into the atmosphere where they could enter the food chain, bioaccumulate, and then cause problems especially in children (mental retardation). Currently lead is at a low level in the U. S. air, but other countries continue to use leaded gasoline.

  12. Since the implementation of the Clean Air Act in 1970, the emissions of the criteria pollutants has decreased. However, there are still problems with pollutants

  13. There are people who are against regulations that reduce pollution

  14. Attacks on Clean Air Act. Why? There are other air pollutants such as toxic substances. Some of these are carcinogenic, others cause reproductive, developmental, or neurological problems Others cause problems for the environment. Some are natural substances (H2S from swamps), but most are the result of human activities The EPA (previously) estimated that due to the Clean Air Act, from 1990 to 1999, these toxic air pollutants decreased by 30%.

  15. Smog is an unhealthy mixture of air pollutants

  16. Industrial smog Industrial Smog (like the London Killer smog of 1952) is a gray air smog. It contains CO2, CO, and some particulates from the burning of fossil fuels. It is not as common as it used to be in developed nations due to regulations, but in developing nations such as China, India and Eastern Europe it poses significant health risks (these areas do not have the regulations and they burn lots of coal). A second component of industrial smog is the weather and when a thermal inversion traps the smog it is more likely to be a health risk.

  17. Photochemical smog Photochemical smog is a brown-air smog. It is formed through light-driven chemical reactions of primary pollutants and normal atmospheric compounds that produce a mix containing over 100 chemicals. This affects many cities.

  18. An enduring classic, this book offers a dramatic and prophetic look at the potential consequences of the escalating destruction of Earth. In this nightmare society, air pollution is so bad that gas masks are commonplace. Infant mortality is up, and everyone seems to suffer from some form of ailment. The water is polluted, and only the poor drink from the tap. The government is ineffectual, and corporate interests scramble to make a profit from water purifiers, gas masks, and organic foods. Environmentalist Austin Train is on the run. The Trainites, environmental activists and sometime terrorists, want him to lead their movement. The government wants him in jail, or preferably, executed. The media wants a circus. Everyone has a plan for Train, but Train has a plan of his own. This suspenseful science fiction drama is now available to a new generation of enthusiasts

  19. Killer Smog on december 5th, 1952, a dense smog enveloped the city of london. from various news accounts, it shutdown the city for four days, and was credited with the death of more than 4,000 people during the fog, and 8,000 afterwards. the fog was also a watershed event for England on the importance of controlling environmental pollution, and resulted in the clean air act of 1956.

  20. Effects of air pollution Health effects include both acute problems (e.g., asthma, eye, possibly emphysema, nose and throat irritation, SOB, even death). People with other illnesses (particularly of the respiratory system), the elderly and children are the most susceptible (chronic effects as well). Environmental effects include acid rain, the damage done to plants by ozone, and even damage to man-made structures. Economic costs: 50 billion/yr. in health care, 5-10 billion/year in ozone crop damage, and the costs to repairing buildings and other structures

  21. Control of Air Pollution includes regulations (like the Clean Air Act), decreased auto emissions, scrubbers, precipitators and filters, and fines. Overall a decrease in the burning of fossil fuels would be beneficial Picture of Beijing China

  22. Ozone Depletion

  23. Ozone is composed of three Os and makes up part of the upper atmosphere. It is important because it screens out 99% of the sun’s ultraviolet radiation.

  24. Since 1985 there have been numerous records of a thinning of this layer (up to 95% depletion in some regions).

  25. Ozone is unstable and it can split into oxygen gas (O2) and O but it can also reform

  26. UV light is absorbed by ozone (which catalyzes the reactions O3 --> O2 + O and O2 --> 2O)

  27. Negative consequences of ozone depletion increased UV light penetration with related increases in skin cancer and cataracts, increased mutations, and possibly a further increase in global warming (more UV light gets through the atmosphere)

  28. How is ozone destroyed? the answer CFCs: Cl + O3 --> ClO + O2 and ClO + O --> Cl + O2. Notice the absence of O2 due to the second reaction so not only is the ozone destroyed but it is lacking one of its building blocks for restoration

  29. Another environmental success story involves ozone. Due to the Montreal Protocol which cut CFC production, the current production and use of CFCs has decreased by 95% since the late 1980s. Scientists have also seen the beginning of a recovery of the ozone.

  30. Acid Deposition

  31. Sources natural events (e.g., volcanos and lightning) and human activities (e..g, burning coal and internal combustion). Sulfur and nitrogen react with oxidizing agents resulting in the formation of acids.

  32. Effects Acid deposition destroys structures and living organisms

  33. Wet reactions result in the formation of acid rain, snow or dew

  34. Dry deposition involves the settling of the acid precursors on surfaces

  35. Acid rain is a world-wide problem. Normal pH of rain 5.6-5.7 but records of pH values of 2.1 or 2.4 have been found in New Hampshire and Scotland respectively.

  36. Indoor Air pollution is a big problem

  37. Global Climate Change

  38. The Greenhouse effect is necessary for life on Earth

  39. Carbon dioxide is the primary greenhouse gas and its concentration in the atmosphere has increased dramatically since the beginning of the Industrial Revolution

  40. Are humans responsible for climate change? The majority of scientists believe that the combustion of fossil fuels and changes in land use play big roles in climate change. A few disagree. The Intergovernmental Panel on Climate Change (IPCC) concludes that major advances in climate modelling and the collection and analysis of data now give scientists “very high confidence” (at least a 9 out of 10 chance of being correct) in their understanding of how human activities are causing the world to warm. This level of confidence is much greater than what could be achieved in 2001 when the IPCC issued its last major report.

  41. Some of the changes that are predicted are: • hot extremes, heat waves and droughts will become more frequent • heavy precipitation events, storms, hurricanes and flooding will become more frequent • sea levels will rise and there will be significant loss of land • weather patterns will change • thousands of animal species and plants will die and become extinct • billions of people will run out of water • food shortages will occur • food and water scarcity will cause civil unrest • political tensions over resources will increase the chance of conflict

  42. Where did the glacier go?

  43. Causes of global climate change include the burning of fossil fuels, solar activity, methane from cows etc.

  44. How to help stop Global Warming? • Reduce • The amount of energy you consume and start using renewable energy sources, such as wind power and solar power.  Sign up for Green Energy with your local power provider.  If they don't have it, then tell them to get it. • Reuse • By using products made with recycled materials.  Make or buy a compost bin to use your organic waste as fertilizer for your trees, shrubs, and garden. • Recycle • All materials to your best ability in your local area and purchase Carbon Offsets.

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