1. Human Impact on the Carbon Cycle and The Albedo Effect
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2. Human Impact on the Carbon Cycle
Mining Fossil Fuels
by mining and burning fossil fuels (petroleum, natural gas, oil) we are returning the stored carbon back into the atmosphere faster than normal
Clearing Vegetation
by clearing vegetation (deforestation, agriculture, urbanization) we are decreasing the amount of carbon removed from the atmosphere through photosynthesis

3. A) The Greenhouse Effect
1. Shorter wavelength of sunlight enter the greenhouse
2. Light is reflected and wavelengths become longer
3. The longer wavelengths are trapped by the glass
This is the same thing that happens to the Earth, only instead of glass trapping the long wavelengths of light and heat it is the greenhouse gasses (CO2, CH4)

4. B) Global Warming
The burning of wood and fossil fuels ( coal, oil, and gas) has caused carbon dioxide levels to triple over the last 40 years

5. Greenhouse Effect

6. C) A Warmer Climate
Problems arising from increasing temperatures include;
decrease in permafrost
snowcaps and glacier melting – increased lake and river levels, possible flooding
desertification – the amount of dry desert land increases

7. The Albedo Effect Albedo – is a measure of how reflective a surface is
- high albedo mean the surface reflects a lot of light
- low albedo means the surface
reflects very little light

8. The Albedo Effect cont
Snow and ice have a very high abledo (very reflective)
If snowcaps and glacier melt, less light will be reflected (more absorbed) and the temperature of the Earth will increase even more
Disrupting the
snow-temperature
feedback cycle

9. Equilibrium and Earth’s Atmosphere
The Earth once contained extremely high levels of carbon dioxide, causing the planet to warm
Microscopic marine life (stromatolites) then began to consume the carbon dioxide and release methane (CH4) (3.5 billion years ago)
The large amounts of methane caused the planet to warm further, increasing the populations of methane producing bacteria

10. Equilibrium and Earth’s Atmosphere
Warm temperatures intensified the water cycle and the weathering of rocks
Eventually the methane caused a cloud around the Earth blocking some sunlight and decreasing the temperature
New cooler temperatures allowed for new photosynthetic bacteria to develop
Oxygen producing bacteria took over causing oxygen levels to increase