Suminder Kaur, Academic content writer at Edumarz
Many gases, including nitrogen, oxygen, carbon dioxide, and water vapour, make up air.
This composition of air is responsible for life on earth.
Planets such as Venus and Mars, the air composition is entirely made up of carbon dioxide. That’s why there is no life on such planets.
Air contains oxygen which is important for all living organisms. They use this oxygen to break down glucose molecules and get energy for their activities.
So it is called the breathe of life.
The Breakdown of glucose molecules to get energy results in the consumption of oxygen and production of carbon dioxide. This process is called combustion.
During photosynthesis, green plants convert carbon dioxide into glucose in the presence of sunlight. This results in the release of oxygen.
This process helps to maintain carbon dioxide – oxygen balance in the environment.
ROLE OF ATMOSPHERE
Air is a bad conductor of heat. Air covers the earth like a blanket.
It prevents the sudden increase in temperature during the day and also slows down the process of escaping heat.
So the atmosphere keeps temperature quite steady for a day or a whole year on earth.
THE MOVEMENT OF AIR : WINDS
When air becomes heated, it rises to the surface, causing a drop in pressure, and cold air rushes in to take its place. Winds are caused by air movement.
These occurrences are the result of changes in our environment caused by air heating and the creation of water vapour. The heating of water bodies and the activity of living creatures produce water vapour.
This rise in temperature creates a low-pressure zone.Cool air from the high pressure zone comes and pushes up the hot air.
Thus, the atmosphere can be heated from below by the radiation that is reflected back by the land or water bodies.
Convection currents form in the air when it is heated.
Factors which influence these winds are – (i) the rotation of the earth. (ii) the presence of mountain ranges in the path of the winds.
Sea breeze – The land heats up quicker than the sea during the day. As a result, hot air rises above the land, while cold air from the sea travels towards the land.
Land breeze – The sea cools down more slowly than the land at night. As a result, hot air rises over the water, while cold air from the land travels towards the sea.