Lesson 19: Structure of the Atmosphere | Layers of the Atmosphere | eLecturepk

Structure of the Atmosphere or Layers of the Atmosphere: In this video we will learn about different layers of the atmosphere. There are five layers of the atmosphere based on temperature are as follows:

1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere
5. Exosphere

Troposphere:

Troposphere is the first layer which is closer to the earth surface with an average height of 12km. The graph of temperature change indicates that air temperature decreases with an increase in an altitude to this layer with the ratio of 6.5 degree Celsius per kilometer. This layer forms clouds, rain, snow fall, hail, fog and storms. 

Stratosphere:

Stratosphere is the second layer with an average height from 12km to 50km. A narrow strip of tropopause separate it from Troposphere. Air doesn't flows in up and down directions but flows parallel to the earth in very fast moving air streams. This is the layer where most Jet Planes fly. Ozone is also formed in this layer. 

Mesosphere:

Mesosphere is the third layer with an average height from 50km to 80km. In this layer temperature again falls down with increase in height. This area reaches the coldest temperature of all the atmosphere i.e. -130 degree or lower. 

Thermosphere:

Thermosphere is the fourth layer with an average height from 80km to 800km. Mesopause separates it from Mesosphere. Oxygen and Nitrogen are important gases in this layer which are present in Ionized form, so a thin light sheet can be seen from the Sky which is called Aurora Borealis. In northern hemisphere and aurora Australis in southern hemisphere. Aurora means a bright thin light sheet that can be seen from the Sky.

Exosphere:

Exosphere is the last layer with an average height from 800km to 60,000km. Thermopause separates it from Thermosphere. Artificial satellites orbit around the surface of the earth in this layer.