Strand:Materials

Lesson: Layers of the Atmosphere

 
Aim/Objectives

Aim: To heighten awareness of the earth's atmosphere.

Pupils will be enabled to:

i)Name the components of air and in what proportion they occur
ii)Name the layers of the atmosphere
iii)Recall salient points about the different layers

 

Materials Needed

Textbook: 'Look Around'- 6th Class (Folens)
'Young Scientist' Vol 3-World Book, Inc.
Scanner, laptop,extension lead,blackboard,white/coloured chalks, paper and pencils/crayons

Content/Methodology

Introduction

What is air? What are its components? Elicit as much information as possible from the children.

Air is made up of a mixture of gases:

78% Nitrogen (N2)
21% Oxygen (O2)
0.3%Carbon Dioxide (CO2)
0.7%other gases

We live at the bottom of an ocean of gases-the atmosphere. These gases make up the air we breathe. We can only survive near the surface of the earth because we need oxygen. As you travel further away from the earth's surface, the atmosphere changes.

 

Development


Layers of gases surround the earth. These are called the troposphere, stratosphere, mesosphere, thermosphere, and exosphere.

1. The lowest layer is the troposphere, where we live. Most clouds are here. The movement of air here is responsible for our weather. This layer extends to 13 km above the earth's surface.

2. The next layer is the stratosphere. It extends from 13 to 50 km above the earth. Aircraft usually fly here, so they are above weather disturbances. The ozone layer is found here. The temperature in the lower stratosphere is about -55 degrees Celsius, the upper stratosphere -2 degrees.

3. The mesophere is the next layer. It extends from 50 km to 80 km. above the earth. If meteors fall into this area, they burn up and become 'shooting stars'.

4. The thermosphere is a very thin layer. Space satellites fly in the lower part.

5. The exosphere -This is the upper layer and there is hardly any air here. Outer space lies beyond the exosphere.

Allow the children a few minutes in groups to compose a mnemonic devise to remember the layes of the atmosphere (e.g. The Scary Monster Threw Emily Out.) Children themselves vote anonymously for their favourite.

Teacher draws a diagram on the blackboard of the layers of the atmosphere. Children suggest pictures to go with each layer (e.g. Stratosphere-aeroplane; Mesosphere-shooting star).

 

Conclusion/Follow Up Activities

Children are given paper and pencils and asked to draw the layers.

 
Back to Lessons Back to Class