Earth’s Atmosphere And The Layers

The Earth’s atmosphere has many layers and each layer has its specific traits. The Earth’s atmosphere has four layers. They are - Troposphere, Stratosphere, Mesosphere, and Thermosphere. The layers are divided based on temperature. The change in the temperature of the atmosphere with altitude helps understand how the atmosphere works. Unlike the changes in pressure and density, the temperature changes are irregular. Based on the temperature gradient, the Earth’s atmosphere is divided into different layers. The temperature gradient is the change in temperature concerning distance. The heat source of the layer help in determining the temperature gradient in each layer.

Troposphere
This layer is known as the lowest layer of the atmosphere. The air that we breathe exists in the troposphere with the weather phenomena such as fog, and rainfall, occur in this layer. The base of the troposphere is warmer than its base because the air on the surface of the Earth absorbs the sun’s energy, gets heated up, and then it starts moving upward.

Stratosphere
It lies above the troposphere. The stratosphere extends up to a height of 50 km and is free of clouds. Due to this, airplanes can fly in the stratosphere for a smooth ride. The Stratosphere is the house of the ozone layer that protects us from the harmful UV rays of the sun. Ozone molecules in the stratosphere absorb high-energy ultraviolet light from the sun and convert it into heat. Due to this reason, the stratosphere gets warmer the higher we go.

Mesosphere
The temperature in this layer grows colder with the altitude as there are few gas molecules in this layer to absorb the Sun’s radiation. The only heat source is the stratosphere below. The mesosphere is extremely cold, the temperature here can drop to as low as -90°C.

Thermosphere and Beyond
The density of molecules in this layer is very low. One gas molecule can travel about a distance of 1 km without colliding with another molecule. Due to this, little energy is transferred, the air here feels very cold. The satellites are used to orbit in the upper part of the thermosphere.

All these layers of the atmosphere have their role and importance. The whole atmosphere around us depends upon these above-mentioned layers.

By- Manshi Bisht

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