> IS OXYGEN SUPPLY DIMINISHING?

IS OXYGEN SUPPLY DIMINISHING?

Posted at: 2015-03-12 
hOW MUCH OXYGEN IS AVAILABLE, AND HOW MUCH DO HUMANS USE.

Well yes. Slightly.

"Well how much does "slightly" mean?"

Ah, let's do a little calculation.

Oxygen is about 21% of the atmosphere.

CO2 has increased from 280 to 400 ppmv.

So O2 (oxygen) has decreased by 120 ppmv.

That is 0.000120 ppmv, or 0.012%

So, maybe the atmospheric oxygen level is now 20.988%

To give that some perspective, if you work at the 1,000 ft level of the empire state building, the oxygen level there is 97% of what it is at street level (sea level).

If you were to go to Denver, the amount of oxygen available to you would be about 83% that available at sea level.

If hurricane Arthur (not a particularly strong hurricane) were to pass directly over you, your available oxygen level would decline 3%.

In fact, if you walk up a flight of stairs, the amount of oxygen available to you would be decreased by more than the decrease caused by the increase in atmospheric CO2.

BTW, thanks for asking. I'd never looked at this before.

EDIT: "How much do humans use?"

Very, very little. Depending on your definition of use.

Let's limit the discussion to breathing. And keep in mind, you probably want to include all animals, not just people.

http://en.wikipedia.org/wiki/Oxygen_cycl...

It seems like the oxygen turnover (plant to animal and back) is something like 1:5000 in the atmosphere, or 0.05% which is something like ALL of the CO2 but a relatively miniscule portion of the oxygen.

The air is about 21% oxygen and has been for millions of years. The air also contains a fraction of a percent CO2. The fraction of CO2 is a little bit higher now, because of all the coal, oil, and gas we burn to make power, and the amount of oxygen has to have gone down by a tiny fraction of a percent to make all that CO2, but the reduction is so small that it is not worth measuring. It is not being monitored as far as I know. Even if we burned all the coal, oil, and gas in the world it would not use up all the oxygen. We would suffocate in the several percent CO2 created long before even half the oxygen were used up. The Apollo 13 crew barely made it back to Earth alive not because they ran out of oxygen, but because there was too much CO2 in the air due the the CO2 scrubbers in the command module not working. They adapted the lunar module CO2 scrubbers to use the command module filters (with duct tape!) to save themselves.

Climate clowns don't have a clue. Hey Dook and linlyons make it seem O2 diminishes when in fact, it doesn't. Carbon dioxide is made of 1 part carbon and 2 parts oxygen (O2). Taking carbon from the ground and adding it to the air is how our atmosphere exchanges carbon. It uses oxygen to transport it into the atmosphere and around the world where it is needed and used. Increased carbon in our atmosphere is the best we can do to help the life cycles of every plant and animal that is living. Oxygen levels stay the same. It's just that a very, very, very, very, small percentage of it has a carbon atom attached to it.

Climate clowns are more concerned with the extra carbon in the atmosphere because it is also considered a greenhouse gas, but a very minor one compared to water vapor. If you can understand how fast clouds can form, then you will understand how little of an effect carbon has in the atmosphere. Carbon dioxide doesn't build up. It dissipates and equalizes. Water vapor condenses and forms clouds in a hurry. Water vapor is what dominates the atmosphere and causes it to change rapidly. Not CO2.

We consume oxygen by breathing, when we use or destroy plants, and when we burn fossil fuels. The first two kinds of consumption are basically offset by the production of oxygen from plants.

Oxygen is about 1/5 of air, carbon dioxide is about 1/2500th, and in the most extreme case imaginable scenario it might go up (over the course of several centuries to come) to something around 1/500th, which would thereby reduce the portion of oxygen in air by about twice that (by about 1/250th of a percent). Other oxygen sinks, such as the oxygen from anthropogenic carbon dioxide going into oceans, are even smaller in effect.

"Oxygen supply diminishing" on a global basis is a non-issue. By analogy, if you were to ingest cyanide, the effect on your body's oxygen levels would be miniscule. The problem would be the EFFECTS of the cyanide on your body's ability to use the oxygen.

http://en.wikipedia.org/wiki/Cyanide_poi...

Increasing carbon dioxide is a concern because it has significant and increasing effects on the global climate, that are mostly bad news for the global economy, not because of the very tiny effect that increasing CO2 has on reducing O2.

Yes, I do believe so. Humans have been using the slash and burn practice for a very long time. We clear more land of trees and plant CROPS THAT MAKE LOTS OF MONEY ! Yet, at some point, even if you are the most wealthiest family on this planet, you won't be able to buy enough enough oxygen.

We must keep our forests and especially the rain forest in tack.

If we really want our earth to continue, we really must stop the destruction of that very thing that keeps us alive !

No oxygen supply is not diminishing. There is just more CO2 in the atmosphere, which doesn't do anything to how much oxygen there is. There is plenty to go around, as 21% of the atmosphere is oxygen. No need to worry.

Oxygen is decreasing in the troposphere at a rate of about 19 ppm per year.

This is not a concern. Even the burning of all fossil fuels on earth would not decrease O2 enough to worry about.

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You can ignore Zippy's nonsense. You question is about O2. He hasn't a clue about the difference between molecules and atoms. You will see many such examples illustrating that climate change deniers are merely ignorant of 6th grade physics.

http://scrippso2.ucsd.edu/

No because the suns rays warm earth as earth rotates to grow food for food and oxygen to keep all species alive. Mike

Thanks for information. I can sleep at night now. How about the problem we have with droughts and flooding. Why are we interested in Mars when we should be interested in Earth, If we in the USA don't start thinking about connecting the two it may be too late? Droughts and Floods, not Earth and Mars. Mars was just an example of government waste, when we more pressing problems.

Maybe in your house, but not in the earth's atmosphere in general.

hOW MUCH OXYGEN IS AVAILABLE, AND HOW MUCH DO HUMANS USE.