The atmosphere is like a blanket of the Earth. It contains many layers. The thickness of the atmosphere is relatively thin compared to the size of the Earth.
The major and significant layers of the atmosphere are:
The last layer in our atmosphere is the exosphere which extends out to 960 km from sea level. This layer consists of a variety of very small quantities of gases including helium, nitrogen, oxygen and argon. Temperatures here can range from 300 ºC to 1650 ºC.
Temperatures in here rise dramatically to about 1480 °C under certain conditions. Among the importance of the thermosphere is in long range radio broadcasting and protection from meteors and obsolete satellites because the high temperatures burn up nearly all the debris coming toward earth. This is because the thermosphere contains charged particles or ions which have the ability to reflect radio waves back to Earth.
The thermosphere can be as high as 120 km.
The mesosphere extends to about 80 km from the Earth. In here the temperature decreases again. Temperatures stop decreasing at the mesopause which is in between the mesosphere and the next layer, the thermosphere.
The stratosphere extends to about 50 km from the Earth's surface. Temperatures increase to 4 °C. At about 24 km above earth, lies the ozone layer which absorbs a large amount of the Sun's ultraviolet.
This layer extends from ground level to between 8 to 16 km high from the sea level. The height of the troposphere at the equator is the highest due to the amount of solar energy reaching earth. The lowest, at the two poles.
This is because warm air expands more compared to cold air.
Temperature drops 1 °C every 165 m. The level at which temperature stops decreasing is called the tropopause. Temperatures there can be as low as -58 °C.
It is in this level where what we call weather occurs.
The proportion of gases in the troposphere:
Nitrogen 78% Oxygen 21% Carbon Dioxide and Noble Gases 01%
The above table can be a bit inaccurate sometimes as proportions of gases in different areas of Earth differ.
Weather balloons used to research weather in the upper layers of the atmosphere