Topic 1-Atmoshere Flashcards
Why is it difficult to be precise about the evolution of the atmosphere?
Nobody has been around long enough to have recorded information about it
What were the main causes of small change in the atmosphere?
Volcanic activity
Human activity - burning fossil fuels
What produced the gases of the early atmosphere?
Volcanic activity
How did the oceans form?
The water vapour from volcanoes condensed to form oceans
How did oxygen levels increase over time, and why did carbon dioxide levels fall?
Photosynthesis- used carbon dioxide, and release oxygen
What were the main gases in earth’s early atmosphere?
Carbon dioxide Water vapour Small amounts of ammonia Methane Nitrogen But no oxygen
What are the main gases in the atmosphere now?
Nitrogen
Oxygen
Small amount of carbon dioxide and water vapour
What happened to the carbon in the earth’s early atmosphere? And what is it called
- The carbon dioxide dissolved in the sea water
- The dissolved carbon dioxide made carbonates.
- Sea animals used carbonates to make calcium carbonate for shells
- When the animals died their shells were deposited as sediment
- The shells were crushed and cemented into limestone, the carbon is trapped in the limestone as calcium carbonate
Dissolution
What is the test for carbon dioxide?
Limewater will go cloudy or milky
What percentage of carbon dioxide is in the atmosphere now?
0.04%
What are the three greenhouse gases?
Methane
Carbon dioxide
Water Vapour
What is Iron seeding?
Iron compounds dissolve in ocean
Causes excess Algi growth
Algi photosynthesises and takes carbon dioxide out of the air
Which human activities cause climate change?
Combustion Deforestation Burning fossil fuels Respiration Intensive cattle farming
What is the greenhouse effect?
Sun beats down on earth
Energy reflects of the earths surface
Green house gases trap energy in the atmosphere
What are the three greenhouse gases?
Carbon dioxide
Methane
Water vapour
