What % of the atmosphere is nitrogen?
80%
What % of the atmosphere is oxygen?
20%
Other than nitrogen and oxygen what gases are found in the atmosphere?
Carbon dioxide, water vapor and noble gases 
When is it believed the atmosphere formed?
4.6 billion years ago
Why is it believed there were high levels of water vapor and Co2 in the earths early atmosphere
It is believed that there was intense volcanic activity which produced water vapor
What is the earths early atmosphere thought to be similar to
The atmosphere of mars
Over time what happened to the water vapor produced by volcanic activity?
It condensed to from oceans
How is it believed that CO2 levels decreased over time?
- carbon dioxide dissolved in oceans
- taken in by plants during photosynthesis
- it became trapped in sedimentary rocks as they formed
Why it thought that oxygen levels have increased over time?
- algae and plants during photosynthesis
When did algae first producing oxygen
2.7 billion years ago
Explain how green house gases cause the earth to warm?
- short wavelength radiation passes through the earths atmosphere
- most of this radiation is absorbed by the earths
- some is re-emoted as long wave length radiation
- this long wavelength radiation is absorbed by greenhouse gases and is trapped in the atmosphere
What human activities contribute to carbon dioxide levels?
- burning fossil fuels
- deforestation
What human activities contribute to methane levels?
- mass farming (cows produce methane)
- landfill
What are the effects of climate change?
- destruction of habitats
- extinction
- migration of species
- rising oceans (loss of land)
What is the definition of carbon footprint?
The total amount of CO2 emitted over the lifecycle of a product
How can you reduce the carbon footprint of a product?
- renewable energy
- reduce transportation e.g produce product domestically
- sustainable materials
- minimize packaging
What are the potential products of burning fuels.
- carbon dioxide
-carbon monoxide - sulfur dioxide
- carbon particles
What is the effect of carbon monoxide on the atmosphere?
- is its a toxic gas
- it is colorless and odorless which means it is difficult to detect
What is the effect of sulfur dioxide on the atmosphere?
Can cause acid rain
What is the effect of carbon particles being released on the earths atmosphere?
- can cause heath problems
- creates a smog
- cause global dimming
What is cruce oil formed from
Plankton
What is the definition of a finite resources
A limited resource
