Atmosphere is the gaseous layer or set of layers surrounding the earth with the help of gravity. It can be understood as the blanket of the earth and helps to maintain proper temperature. Earth is the third planet in our solar system and it is the only planet having Atmosphere. Atmosphere plays an important role in our daily life. Sources of oxygen, rain, dew, fog, all lie in the atmosphere. The atmosphere has different layers with different thickness, structure and functions. The total thickness of the atmosphere is 900 km. In this article, We will learn about the layers of atmosphere in order, going from bottom to top. Before we dive into the detailed overview of all layers, we have made a quick overview table showing the layers of atmosphere with height from lowest to highest:-
|Layers of Atmosphere in Order||Height From Earth Surface|
|1. Troposphere||12 KM|
|2. Stratosphere||50 KM|
|3. Mesosphere||85 KM|
|4. Thermosphere||700 KM|
|5. Exosphere||1000 KM and Above|
Layers of Atmosphere in Order
There are 5 different layers of atmosphere in order namely, Troposphere, Stratosphere, Mesosphere, Thermosphere and Exosphere. Together they surround the earth from all sides. Each layer has its own role and importance. Here, We have tried to include all the layers with detailed information.
Troposphere lies first layer of atmosphere in order from bottom to top. This layer is in direct touch with the earth. The thickness of this layer is 12 km. It contains almost 75 % of all the gases in the atmosphere along with all water vapour (99%). The gases found in this layer are:-
|CO2||(0.03 – 0.04) %|
As we move upward from bottom to top, temperature decreases in this layer. Meteorological phenomena like Raining, Strom, Thunder, Tornado all occur in this layer. Most of the dust particles also lie in the troposphere. Cloud occurs in this layer. Hot air balloons fly within the troposphere. More importantly, we can say this is the place where life exists. All the trees, animals, and microbes lie in this layer.
The Stratosphere is second in layer of atmosphere. It extends up to 50 km above the earth surface. It is one of the most important layers because this layer includes ozone. This ozone is like Protective shield on our earth. Ozone prevents UV rays from reaching Earth. Ozone gas (O3) is about 15 to 35 km in the stratosphere layer. Temperature rises with rise in altitude. The boundary area between troposphere and stratosphere is tropopause. Aeroplanes fly in this layer because of no turbulence in this layer.
This layer lies in middle. The boundary area between stratosphere and mesosphere is called Stratopause. Air molecules present in this layer absorb electromagnetic radiation coming from the sun. Most meteors burn upon entry into the mesosphere. The phenomenon of shooting stars occurs in this layer. It extends up to 85 km from Earth’s atmosphere. The temperature decreases as altitude increases. It is the coldest layer with a temperature of about -90°C. Just below Mesopause, the mesosphere layer contains noctilucent clouds (night-shining clouds). They are the highest cloud in the atmosphere and is made up of ice crystals.
This is the fourth layer in the atmosphere. It is the thickest layer in the atmosphere. The boundary between the Thermosphere and Mesosphere is Mesopause. It has very thin air. Only the lightest gases like Helium, Hydrogen and Oxygen lie in this layer. The temperature is very hot at this layer. Lower part of the thermosphere contains the ionosphere where atoms ionize. This layer absorbs UV rays and high energy x-rays which cause ionization. It extends from Mesopause to 700 km above the surface of the Earth. The temperature ranges from 2000 ° C to 500 ° C.
Exo means outside. It is the outermost layer of the atmosphere in order. This layer extends from the top of the thermosphere to 10, 000 km above the earth surface. The effect of earth’s gravity is very less in this atmosphere where atoms and molecules escape into space. This layer can contain low densities gases like hydrogen, helium, oxygen, nitrogen, and carbon dioxide. Satellites revolve in this layer.
To warp up, Troposphere, Stratosphere, Mesosphere, Thermosphere and Exosphere are the layers of atmosphere in order from bottom to top. They all play important role in different phenomena. If any one of the layer is absent, then – we can’t imagine the life on Earth. These layers also helps to maintain heat budget, meaning they absorb and reflect light and heat energy which helps to maintain the more or less constant temperature on earth which makes it possible for us to survive without any harsh.