Is air a renewable source?

Answer 1

Technically no, but for all intents and purposes yes.

Technically we are leaking our atmosphere to outer space. There is a finite amount of material on the planet and matter coming to the planet (meteors) so the atmosphere could run out some day. But, the sun would turn into a red giant and explode before that happened.

The Earth is considered to be a closed system with all matter recycled. Some air escapes into space, and some land falls onto the earth from space as meteorites. But, these two sources are minor and ignored. The loss or contribution they make is insignificant.

Gases come from rock that is broken down by the heat of the earth and released into the atmosphere. So the earth is actually still making its atmosphere. The atmosphere can be absorbed by planets and animals. When they die the atmosphere and carbon inside of them is considered fixed. It is buried and lost, but the earth is dynamic. The continents are shifting and old land is going underground while new land is coming up. That means that anything that is on the crust will eventually be recycled back into the earth. Left undisturbed the air carbon breathing in by plants from before the age of the dinosaurs would be buried and under pressure converted to rock or mineral like oil. That deposit would be on a continent and as the continent moves or as volcanoes erupt more land is built up over the deposit eventually the deposit will be reabsorbed into the earth’s mantel.

Humans have stopped this cycle by digging up and burning this material.

It took millions of years to transform plants to coal and oil. It took man a few thousand years to return a lot of that back to the atmosphere, most of it done in the last 100 years. The CO2 we have today was once breathed in by dinosaurs and became part of them. It was locked inside the earth when the dinosaur died and was buried by time. So we are taking millions of years of CO2 emissions locked inside of plants and animals and returning them to the atmosphere in a few hundred years. This is why global warming makes sense. We are burning too much and have been doing it for a very long time. Think about it; since men still lived in caves we have burned enough trees to forest the entire planet several times. All of that CO2 can’t be easily removed and a lot of it is still there in the air we breathe.

Frodo is pointing out a minor part of the cycle. Basically the crust of the earth is being transformed into plants or into the atmosphere and eventually it is either washed into the ocean, or buried underground. That is the natural cycle. Mankind has changed that cycle by setting fire to a great deal of it before it could return to the earth; leaving it stuck in the atmosphere.

Answer 2

Yes, because when we breathe in oxygen in the air, we'll always give out carbon dioxide. And green plants will always take in carbon dioxide to do photosynthesis and give off oxygen . It's only that the quality of the air will depend largely on the amount of industrial wastes & other pollutants that people add in the atmosphere. As it is, polluted air harms our health, injures animals and plants, damages buildings and even affects weather.

Answer 3

Rain cleans the junk out. Plants put more oxygen in. Yes.