Layers of the Earth's Atmosphere

Layers of the Earth's Atmosphere 

The atmosphere is divided into five layers. It is thickest near the surface and thins out with height until it eventually merges with space. 

1) The troposphere is the first layer above the surface and contains half of the Earth's atmosphere. Weather occurs in this layer. 
2) Many jet aircrafts fly in the stratosphere because it is very stable. Also, the ozone layer absorbs harmful rays from the Sun.
3) Meteors or rock fragments burn up in the mesosphere.
4) The thermosphere is a layer with auroras. It is also where the space shuttle orbits. 
5) The atmosphere merges into space in the extremely thin exosphere. This is the upper limit of our atmosphere. 
The troposphere is the lowest layer of the Earth's atmosphere. The air is very well mixed and the temperature decreases with altitude. 


1-Troposphere

Air in the troposphere is heated from the ground up. The surface of the Earth absorbs energy and heats up faster than the air does. The heat is spread through the troposphere because the air is slightly unstable. 
Weather occurs in the Earth's troposphere. 


2-Stratosphere

The top of the stratosphere occurs at 50 km (31 miles) altitude. 
Ozone, an unusual type of oxygen molecule that is relatively abundant in the stratosphere, heats this layer as it absorbs energy from incoming ultraviolet radiation from the Sun. Temperatures rise as one moves upward through the stratosphere. This is exactly the opposite of the behavior in the troposphere in which we live, where temperatures drop with increasing altitude

3-Mesosphere

The mesosphere starts at 50 km (31 miles) above Earth's surface and goes up to 85 km (53 miles) high.What do we know about the mesosphere? Most meteors from space burn up in this layer. A special type of clouds, called "noctilucent clouds", sometimes forms in the mesosphere near the North and South Poles. These clouds are strange because they form much, much higher up than any other type of cloud. There are also odd types of lightning in the mesosphere. These types of lightning, called "sprites" and "ELVES", appear dozens of miles above 

4-Thermosphere

It extends from about 90 km (56 miles) to between 500 and 1,000 km (311 to 621 miles) above our planet.
Temperatures climb sharply in the lower thermosphere (below 200 to 300 km altitude), then level off and hold fairly steady with increasing altitude above that height. Solar activity strongly influences temperature in the thermosphere. The thermosphere is typically about 200° C (360° F) hotter in the daytime than at night, and roughly 500° C (900° F) hotter when the Sun is very active than at other times. Temperatures in the upper thermosphere can range from about 500° C (932° F) to 2,000° C (3,632° F) or higher. 


5-Exosphere

Very high up, the Earth's atmosphere becomes very thin. The region where atoms and molecules escape into space is referred to as the exosphere. The exosphere is on top of the thermosphere.