Dear students,

We continue to study air and the theme of the lesson today is “The Layers of Earth's Atmosphere.”

The blanket of air that wraps around the earth stretches upwards for hun­dreds of miles. These layers are shown in the diagram below.

  The earth's atmosphere has four layers. As each layer gradually merges into the layer above it, air becomes thinner and thinner until outer space is reached. There is no air in outer space, which is limitless. In the layers colored blue on the diagram, temperatures decrease with altitude. In the layers colored orange and yellow on the diagram, temperatures increase with altitude.

The top three layers contain only about 1 percent of the air in the atmosphere, the troposphere contains the other 99 percent.

Electrically-charged particles in the ionosphere shield the earth by reflecting many ultraviolet and other harmful rays back into outer space, these particles also help to give the sky its blue color to viewers on the earth.

During the next lesson we will study the layers of atmosphere more particularly. 

Name

Home work

Look at the diagram and name the layers that make up the earth's atmosphere.
Which layer is closest to the earth?
Which one is farthest from the earth?

What percent of the air does the troposphere contain?

How does air change from the troposphere towards the exosphere?

I’m looking forward the letters from you,

Mrs. Nicolaev