Question

Why is the atmosphere essential for life?

Answer 1

Hint: Atmosphere is a collection of gases which surround the Earth and help in our survival. The atmosphere is divided into different layers and each layer has its own functions.

Complete answer: - Atmosphere is essential for life because it has oxygen and other useful gases which humans need for their survival. The different layers of the atmosphere which help in our survival are:
a. The Troposphere - This layer is the lowest part of the atmosphere. It contains most of the weather factors like clouds, rain, and snow. In this layer of the atmosphere, the temperature gets colder as the distance from the earth increases. The troposphere comprises about 75% of all the air in the atmosphere and almost all of the water vapour.
b. The Stratosphere- This layer extends from the troposphere. It has most of the ozone present in the atmosphere. The increase in temperature with height happens because of the absorption of ultraviolet radiation from the sun by the ozone layer. By absorbing dangerous UV radiation, the ozone in the stratosphere protects humans from skin cancer and other health damage.
c. The Mesosphere- In this layer which is above the stratosphere, the temperature in this layer can go down to as low as about -90°C.
d. The Ionosphere and thermosphere - The thermosphere comes above the mesosphere, the ionosphere contains ions which facilitate radio communication.
e. The Exosphere- This layer is about 500 km from the land, it is called the exosphere. It contains mainly oxygen and hydrogen atoms, and some of them also fade into space.

Note: The atmosphere is made up of 78% nitrogen, 21% oxygen, and smaller amounts of argon, carbon dioxide and helium among other gases. Pollutants in the atmosphere include smoke, toxic gasses, dust and volcano ash. Roughly 80% of the weight of the atmosphere is carried in the troposphere.