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.