Earth's Atmosphere Flashcards
How old is the Earth?
4.6 billion years
Where did the original atmosphere come from?
Volcanic activity
What gases were released by volcanoes?
Water vapour, carbon dioxide, methane, ammonia, nitrogen
How were the oceans formed?
Water vapour cooled and condensed
How did carbon dioxide levels decrease in the early atmosphere?
Dissolved in oceans, formed sedimentary rock, photosynthesis by algae/plants
What gas made up most of the early atmosphere?
Carbon dioxide
How did oxygen increase in the early atmosphere?
Released by photosynthesis by algae/plants
What gas makes up most of the current atmosphere?
Nitrogen
How much of the current atmosphere is nitrogen?
78%
How much of the current atmosphere is oxygen?
21%
How much of the current atmosphere is carbon dioxide?
0.04%
How is carbon removed from the atmosphere?
Photosynthesis by plants
How is carbon added to the atmosphere?
Respiration by animals and plants, combustion of fossil fuels, decomposition of waste
What is a carbon sink?
A store of carbon, not in the atmosphere
Name a carbon sink
Oceans, sedimentary rocks, fossil fuels, marine organism’s shells
What is the greenhouse effect?
The trapping of infrared radiation by gases in the atmosphere
Name three greenhouse gases
Carbon dioxide, water vapour, methane, oxides of nitrogen
What type of waves are absorbed by greenhouse gases?
Long wavelength