Air and Pollution

  • Atmospheric Layers and Composition

  • Layers of the Atmosphere

  • Troposphere contains 75-80% of Earth's air mass and extends up to 17 km at the equator; dominated by nitrogen (78%) and oxygen (21%)

  • Ozone layer found in the stratosphere (17-48 km) with less volume but higher ozone content; protects from UV rays

  • Mesosphere and thermosphere complete the layers of the atmosphere

  • Composition of the Troposphere

  • Main gases inhaled are nitrogen (78%) and oxygen (21%) with traces of argon, carbon dioxide, water vapor, and other gases

  • Greenhouse gases like H2O, CO2, CH4, N2O trap heat in the troposphere

  • Remaining gases include methane, carbon monoxide, ozone, and nitrous oxide

  • Air Pollution and Greenhouse Gases

  • Air Pollution Sources

  • Natural sources like wildfires, volcanic eruptions, and plant emissions

  • Human sources from industries, urban areas, and transportation

  • Greenhouse Gases

  • H2O, CO2, CH4, N2O absorb and release energy, contributing to global warming

  • Methane is a potent greenhouse gas, with sources from natural wetlands and human activities like livestock

  • Types of Air Pollutants

  • Primary & Secondary Pollutants

  • Primary pollutants are emitted directly into the air, while secondary pollutants form through interactions

  • Improvements in air pollution over the years, but still a concern in many areas

  • Common Air Pollutants

  • CO & CO2 are colorless, toxic gases from incomplete combustion

  • Nitrogen Oxide & Nitric Acid irritate respiratory systems and contribute to acid rain

  • Sulfur dioxide & sulfuric acid from natural and human sources cause respiratory issues and acid rain

  • Particulate matter includes solid and liquid droplets suspended in the air, affecting air quality

  • Ozone, VOCs, and smog are also significant air pollutants

  • Effects and Regulation of Air Pollution

  • Health and Environmental Effects

  • Prolonged exposure to air pollution leads to respiratory diseases, cardiovascular issues, and environmental damage

  • Acid deposition from pollutants harms plant life, soil quality, and aquatic ecosystems

  • Regulation and Control Measures

  • Efforts to reduce air pollution include emission trading, clean air acts, and national standards for pollutants

  • Strategies to lower acid deposition involve prevention and clean-up methods

  • Weather, Climate, and Climate Change

  • Weather vs. Climate

  • Weather refers to daily physical conditions like temperature, precipitation, and wind

  • Climate encompasses long-term patterns of atmospheric conditions over decades to millennia

  • Factors Influencing Climate

  • Natural factors like orbit variations, volcanic eruptions, and oceanic changes affect climate

  • Uneven heating of the Earth, ocean currents, and air circulation patterns play crucial roles