The Atmosphere Today

Question 1

How do small changes in the atmosphere occur?

Answer 1

Through volcanic activity

Through human activity- burning fossil fuels, farming and deforestation

Question 2

Describe the current composition of the atmosphere and interpret data sources showing this information.

Answer 2

Nitrogen and oxygen are the most abundant gases in the atmosphere, making up about 99% between them. Small amount of other gases make up the other 1%. There is also water vapour present in the atmosphere. Amount of water vapour changes day to day- not included when giving the composition of dry air.

Question 3

Where did nitrogen come from?

Answer 3

One theory is volcanoes released oxygen when the earth was young- always contained a lot of nitrogen.
Another theory is that most of the nitrogen was added to the atmosphere gradually due to the reactions of nitrogen-containing compounds released from volcanoes

Question 4

Percentages for the gases in dry air?

Answer 4

Nitrogen - N(small 2) - 78%
Oxygen- O(small 2)- 21%
Argon- Ar- 0.9%
Carbon dioxide- CO(small 2)- 0.04%
Other gases-     - traces