1 / 19

Understanding the Atmosphere: Composition, Pressure, Pollution, and Health Impacts

Explore the intricate layers of the Earth's atmosphere in this comprehensive overview. Discover the composition of gases such as nitrogen, oxygen, and trace greenhouse gases, and learn how gravity affects their density and distribution. Gain insights into atmospheric pressure, barometers, and the impact of pollutants like sulfur dioxide and mercury on health and the environment. Understand the significance of the Clean Air Act, acid rain, and ongoing challenges such as the ozone hole. This knowledge is vital for protecting our planet's future.

lecea
Télécharger la présentation

Understanding the Atmosphere: Composition, Pressure, Pollution, and Health Impacts

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The AtmosphereChapter 17 100.1 km Mach 2.9 Watch

  2. What’s In a Breath? 0.934% (Ne, He, H2, Kr, CH4, H2S) 0.036% (a greenhouse gas responsible for planet being warm) <0.03% 20.916% (allows: burning, rust, respiration) 78.084% (reacts with nothing)

  3. And the Other Stuff… Bologna, Italy

  4. “Thickness” of the Atmosphere • Gases zing about at 950 mph (425 m/sec) • Gravity concentrates them near the surface • Density decreases upward • Boiling water at high elevation

  5. Atmospheric Pressure • 1-m Mercury Barometers • Inches or mm of mercury • 29.92 in = 1 atmosphere (avg) at mean sea level • 1 atm ~ 1 bar • The weatherman • Old men and mercury • Aneroid Barometers

  6. Little ozone, temperature decreases rapidly Oxygen  Ozone (heated by Sun, absorbs harmful radiation) Air too dense to rise beyond tropopause Temperature in the Atmosphere Heated directly by high-energy X-rays and UV radiation Space Ship One Water vapor, clouds, storms and bad weather (heated by Earth’s radiant heat)

  7. Ozone and You • In stratosphere: • O2  2O O + O2 O3 (ozone) • Ozone very efficient at absorbing UV • In troposphere: • N2 + O2 + heat  2 NO  …  O3 • Linked to heart disease, cancer, asthma, loss of lung function

  8. CFCs • 1970s, used in almost all refrigerators, air conditioners, propellants in aerosol cans • Stable • Work their way Into atmosphere and Destroy ozone … Come Back!

  9. The Ozone Hole • Not literally a “hole”—more like a male pattern baldness

  10. Other Pollutants • Donora, PA • 27-31 October 1948 • Smog settled over city • Sulfuric acid, nitrogen dioxide, fluorine trapped in valley by stagnant air • 20 dead, 800 animals  respiratory illnesses • Plants dead in half-mile radius of steel, zinc works • 1/3 of town’s 14,000 people were sick Donora at noon, Oct. 29, 1948

  11. Clean Air Act of 1970 • Amendment to CAA of ’63 Smog over Shanghai Primary Standards to protect “sensitive” groups: elderly, children, ashtmatics Secondary Standards to protect against decreased visibility, damage to animals, vegetation, crops, and buildings Superscripts=exceptions 1/y

  12. Advancing the Clean Air Act • 1970 Amendments: • Environmental Protection Agency (EPA) to determine the limit of industrial pollutants • Controlling auto emissions by 90% • 1990 Amendments: • Contributors to ozone depletion phased out • Rules on toxic waste and acid rain

  13. The Burning of Hydrocarbons • Form CO2 and/or water during burning

  14. Impurities and Incomplete Burning • Benzene, methane (CH4), carbon monoxide (CO), sulfur dioxide (SO2), nitrogen oxide (NO2) • Mercury in rivers near Kittanning, PA: • Fish at 3.1-19x concentration of mercury than store-bought • Mercury linked to neurological disorders • 5-8x EPA’s acceptable risk depending on age • Minamata Disease Actually, the plant in Seward, PA

  15. Acid Rain • In moist air, you get sulfuric and nitric acids which dissolve in water vapor, fall as rain • pH  7.0 (neutral) • Normal rain pH ~5.7 due to CO2 • 1986, in southern CA a fog reached pH = 1.7

  16. Acid Rain • Too weak to irritate human skin but is devastating to delicate organisms and rock • Damages mountain forests • Germany 1982-1995: 8% unhealthy to 50% SICK • Acidifies lakes causing massive fish kills Acid-rain on forest in Jizera mountains of Czeck Repulic Actually, acid-mine drainage (this is extreme limit)

  17. Rapidly weathers stone monuments • U.S. several billion $/yr repairing damage

  18. Other Toxic Volatiles • Chemicals that readily evaporate into air • Pesticides – some is carried off by wind • Dioxin – formed in backyard burn barrels or wherever plastic polyvinyl chloride is burned • Gets into grass, ruminants • We eat meat: 0.0000000001 g/day • EPA: “at or near levels associated with adverse health effects” • Could cause cancer, birth defects, reproductive and immune disorders V child, blamed on Agent Orange

  19. Particulates and Aerosols • Particulate: Small pieces of solid matter • Aerosols: Small particles suspended in air • Fly ash: Smoke, soot, clay/stuff that can’t burn

More Related