Comprehensive Notes on Greenhouse Gases and Their Impact on Climate

Greenhouse Gases and Their Effects

• Essential Components of Atmosphere:

  • Water vapor is a key component of greenhouse gases.
  • Greenhouse gases absorb most of the sunlight that reaches Earth, making life possible.
  • Average temperature maintained by greenhouse gases: 59°F.

• Role of Nitrogen and Oxygen:

  • Nitrogen and oxygen do not absorb solar radiation.

• Milankovitch Cycles:

  • Refers to the wobbles in Earth’s tilt and orbital path around the Sun.
  • These tilting angles vary between 22 to 25 degrees.

• Effects of Reduced Tilt:

  • Milder summers and winters.
  • Increased potential for ice build-up.
  • Prevention of complete summer ice melt in polar regions.

• Global Warming Potential (GWP):

  • Definition: The relative ability of one molecule of a greenhouse gas to contribute to warming compared to carbon dioxide (CO2).

• Types of Greenhouse Gases:

  • Carbon Dioxide (CO2)
  • Source: Burning fossil fuels (coal, natural gas, and oil).
  • Fluorinated Gases
  • Source: Industrial processes.
  • Nitrous Oxide (N2O)
  • Source: Agricultural activities, industrial processes, and combustion of fossil fuels and solid waste.
  • Methane (CH4)
  • Source: Production and transport of coal, natural gas, and oil.

• Significance of CO2:

  • Most significant greenhouse gas contributing to global warming caused by human activities.
  • Primary sources include burning fossil fuels, biomass burning, deforestation, and cellular respiration.

• Methane Production:

  • Naturally produced in anaerobic environments.
  • Primary sources include anaerobic decomposition, gas drilling and production, and coal mining.

• Nitrous Oxide (N2O):

  • Has a higher global warming potential than CO2 and CH4.
  • Primary sources include soil bacteria, fertilizer overuse, anaerobic decomposition, and sewage treatment.

Human Impact on Climate

• Particulate Matter and Albedo Effect:
  • Human activities contribute to increased levels of carbon black, soot, dust, and particulates in the atmosphere.
  • This decreases the albedo of light-colored surfaces, leading to greater absorption of solar radiation and resulting in climate warming.