What's in the Air?

The Air

• The atmosphere is divided vertically into four regions- the troposphere, the stratosphere, the mesosphere and finally the thermosphere.
• The higher up you go, the less dense the atmosphere is.
• The atmosphere is a mixture of many gases. 90% of all molecules in the atmosphere are found in the troposphere.

The concentrations of the gases in the table above are measured in parts per million. This measure is adequate when small concentrations are involved. 35 ppm represents a…