1 / 38

Air Pollution

Air Pollution. Chapter 18. Core Case Study: South Asia’s Massive Brown Cloud. Asian Brown Cloud Causes Chemical composition Areas impacted Air pollution connects the world Steps taken in China and India to reduce air pollution. Core Case Study: South Asia’s Massive Brown Cloud. Causes

garima
Download Presentation

Air Pollution

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. Air Pollution Chapter 18

  2. Core Case Study: South Asia’s Massive Brown Cloud • Asian Brown Cloud • Causes • Chemical composition • Areas impacted • Air pollution connects the world • Steps taken in China and India to reduce air pollution

  3. Core Case Study: South Asia’s Massive Brown Cloud • Causes • Drought • Clearing of forests • Chemical composition • Dust, smoke, ash • Acidic compounds, soot, toxic metals • Fly ash from burning fossil fuels

  4. Core Case Study: South Asia’s Massive Brown Cloud Areas impacted • Does not stay put • Northern China to Seoul South Korea across the Pacific to the United States

  5. Core Case Study: South Asia’s Massive Brown Cloud • Beneath the cloud • Photosynthesis reduced by ~7% • Cooling Effect • Above the cloud • Warming

  6. The Asian Brown Cloud

  7. Air Pollution in Shanghai, China

  8. 18-1 What Is the Nature of the Atmosphere? • Concept 18-1 The atmosphere is structured in layers, including the troposphere, which supports life, and the stratosphere, which contains the protective ozone layer.

  9. The Atmosphere Consists of Several Layers • Atmosphere varies in • Density • Atmospheric pressure

  10. Air Movements in the Troposphere Play a Key Role in Earth’s Weather and Climate • Troposphere • 75–80% of the earth’s air mass • Closet to the earth's surface • Chemical composition of air • Rising and falling air currents: weather and climate • Involved in chemical cycling

  11. Chemical Composition

  12. The Stratosphere Is Our Global Sunscreen • Stratosphere • Similar composition to the troposphere, with 2 exceptions • Much less water • O3, ozone layer, filters UV • Formation • Location

  13. Atmospheric pressure (millibars) 1,000 200 0 400 600 800 120 75 Temperature 110 65 Thermosphere 100 90 55 Mesopause 80 Mesosphere 45 70 Altitude (kilometers) Altitude (miles) 60 Stratopause 35 50 Stratosphere 40 25 30 Tropopause 15 Ozone layer 20 10 Pressure Troposphere 5 (Sea level) 0 Pressure = 1,000 millibars at ground level –80 80 40 120 –40 0 Temperature (˚C) Fig. 18-3, p. 470

  14. Section 18-2 What are the Major Outdoor Air Pollution Problems?

  15. 18-2 What Are the Major Outdoor Pollution Problems? • Concept 18-2 Pollutants mix in the air to form industrial smog, mostly the result of burning coal, and photochemical smog, caused by motor vehicle, industrial, and power plant emissions.

  16. Air Pollution Comes from Natural and Human Sources (1) • Air pollution • Natural sources • Dust blown by wind • Pollutants from wildfires and volcanoes • Volatile organics released by plants • Withdrawing groundwater

  17. Air Pollution Comes from Natural and Human Sources (2) • Human sources: mostly in industrialized and/or urban areas • Stationary sources • Mobile sources

  18. Case Study: Air Pollution in the Past: The Bad Old Days • Discovery of fire • Middle Ages • Burning of wood • Industrial Revolution • Burning of fossil fuels

  19. Case Study: Air Pollution in the Past: The Bad Old Days • London, England • 1850s • 1880 2200 killed • 1911 1100 killed • 1952: yellow fog; 4,000-12,000 killed

  20. Case Study: Air Pollution in the Past: The Bad Old Days • United States • 1948: Donora, PA; first U.S. air pollution disaster – 6, 000 sick, 20 dead • 1963: New York City • Killed 300 • Global problem

  21. Some Pollutants in the Atmosphere Combine to Form Other Pollutants • Primary pollutants • Secondary pollutants • Air quality improving in developed countries • Air pollution control laws • Much more needs to be done in developing countries • Indoor pollution: big threat to the poor

  22. Indoor Air Pollution

  23. Sources and Types of Air Pollutants

  24. What Are the Major Outdoor Air Pollutants? • Carbon oxides • Carbon monoxide (CO) • Carbon dioxide (CO2) • Sources • Human health and environmental impact

  25. What Are the Major Outdoor Air Pollutants? • Nitrogen oxides (NO) and nitric acid (HNO3) • Sources • Acid deposition • Photochemical smog • Human health and environmental impact • Sulfur dioxide (SO2) and sulfuric acid (H2SO4) • Sources • Human health and environmental impact

  26. What Are the Major Outdoor Air Pollutants? • Particulates • Suspended particulate matter (SPM) • Fine • Ultrafine • Sources • Human health and environmental impact

  27. What Are the Major Outdoor Air Pollutants? • Ozone (O3) • Sources • Human and environmental impact • Volatile organic compounds (VOCs) • Hydrocarbons and terpenes • Sources • Human and environmental impact

  28. Chemical Reactions That Form Major Outdoor Air Pollutants

  29. Statue Corroded by Acid Deposition and Other Forms of Air Pollution, RI, U.S.

  30. Burning Coal Produces Industrial Smog • Chemical composition of industrial smog • Reduction of this smog in urban cities of the United States • China and smog • Human deaths

  31. How Pollutants Are Formed from Burning Coal and Oil, Leading to Industrial Smog

  32. Sunlight Plus Cars Equals Photochemical Smog • Photochemical Smog • Chemical composition • Sources • VOCs + NO2 + Heat + Sunlight yields • Ground level O3 and other photochemical oxidants • Aldehydes • Other secondary pollutants • Human health and environmental impact

  33. A Model of How Pollutants That Make Up Photochemicals Are Formed

  34. Photochemical Smog in Santiago, Chile

  35. Several Factors Can Decrease or Increase Outdoor Air Pollution • Outdoor air pollution may be decreased by • Settling of particles due to gravity • Rain and snow • Salty sea spray from the ocean • Winds • Chemical reactions

  36. Several Factors Can Decrease or Increase Outdoor Air Pollution (2) • Outdoor air pollution may be increased by • Urban buildings • Hills and mountains • High temperatures • Emissions of VOCs from certain trees and plants • Grasshopper effect • Temperature inversions

  37. A Temperature Inversion

  38. 18-3 What Is Acid Deposition and Why Is It a Problem? • Concept 18-3 Acid deposition is caused mainly by coal-burning power plant and motor vehicle emissions, and in some regions, threatens human health, aquatic life and ecosystems, forests, and human-built structures.

More Related