This presentation gives an idea about our atmosphere.

2. ATMOSPHERE
The atmosphere is a thin layer of air that protects
the Earth’s surface from extreme temperatures
and harmful sun rays.

3. COMPOSITION OF ATMOSPHERE
Earth’s atmosphere is a
thin layer of gases
- 78% Nitrogen
- 20.99% Oxygen
-0.03% Carbon Dioxide
- 0.98% Other Gases

4. LAYERS OF ATMOSPHERE
 There are 4 layers of
atmosphere. They are1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere

5. TROPOSPHERE
This is the layer that is
closest to the earth
surface.
It extends up to 11 km
above the surface.
Contains 99% of water
vapor and 75% of
atmospheric gases.

6. STRATOSPHERE
It is directly above the
Troposphere.
Extended from 11 km to
50 km above Earth’s
surface.
Contains “Ozone Layer”
which absorbs harmful
ultraviolet rays coming
from the Sun.

7. MESOSPHERE
Extends from the top of
the Stratosphere up to 85
km above Earth’s surface.
This is the coldest
atmospheric layer having
little ozone.
Ionosphere present here.

8. THERMOSPHERE
This is the highest layer
of the atmosphere.
It’s height ranges from
85-500 km above Earth’s
surface.
Hottest layer of the
atmosphere.
Presence of Ionosphere.

9. UPPER LAYER OF ATMOSPHERE
• Exosphere-
The atmosphere merges into space in the
extremely thin exosphere. This is the upper limit of
our atmosphere.

10. Temperature in atmospheric layers
The troposphere is warmed primarily by the Earth’s
surface; temperature decreases as altitude increases in
this layer.
Temperature increases as altitude increases in the
stratosphere, particularly in the upper portion – ozone
Temperature decreases with altitude in the mesosphere
Thermosphere and exosphere are the first to receive
Sun’s rays, so they are very hot.