Why Carbon dioxide is as necessary as Oxygen(and maybe even more)

You all would have probably heard and learned that how much oxygen is necessary for life to exist and without it, you will not be able to survive. Plants and trees give off oxygen by the process of photosynthesis that we breathe and as a reaction, we exhale air with mostly carbon dioxide. Oxygen is necessary for the oxidation of various substances and also plays a vital role in industrial use. It constitutes about 21% of our atmospheric air.

But what if it told you that carbon dioxide is also really necessary for us and so much so that life would not be even possible in the first place without it. You may ask how and that is what t I am going to explain.

Before explaining why CO 2 is so important, we have to understand how the earth receives energy in the form of light from the sun and reacts after that. So the sun slams the Earth's surface with a ton of electromagnetic radiation which we receive as heat energy. The electromagnetic radiation given by the sun is mostly in the visible spectrum of light and a little bit in the infrared and ultraviolet region. The atmosphere of earth behaves transparently to these visible radiations and the light finally hits the ground. No, what happens is that the ground re-radiates most of this energy back to the atmosphere but this time the radiated energy from the surface is from the infrared region. Various molecules like Carbon dioxide and water vapor are excellent in trapping these infrared radiations and that's what makes the atmosphere heat up, not the direct light and heat received from the sun! A rather popular term in science is known as the Greenhouse effect.

So you might ask then how is it any beneficial and which is that if particulates and molecules such as that of water vapor and carbon dioxide were not present in the atmosphere then this re-radiated energy from the surface of the earth would escape back to space without warming the atmosphere. This warming up of the atmosphere is of so much importance that without these molecules the temperature of the atmosphere would be below zero degrees celsius nowhere near suitable for life to harbor as well as only for that reason the average Earth surface temperature is only 14 degrees celsius as it radiates back the light energy that it receives.

Now I think you got the point of the topic but these days the problem has averted and the concentration of these gases is increasing ( Global Warming) which ultimately leads to the overheating of the atmosphere and creates problems for various life cycles and life forms.