It is.
"From 1991 through 2005, the O2 content of the atmosphere has dropped by 0.00248% (248 per meg) of it's initial amount. The rate is mostly explained by the global combustion of fossil-fuel over this period, although the actual rate is slightly smaller than expected from fossil-fuel alone. The difference evidently reflects a global imballance between photosynthesis and respiration."
http://www.esrl.noaa.gov/gmd/obop/mlo/pr...
Here's a graph of the oxygen depletion
http://www.esrl.noaa.gov/gmd/obop/mlo/pr...
Looks dramatic doesn't it? until you realise that the atmosphere is 20% oxygen, and graph shows a drop in oxygen concentration of 2 thousandths of a percent. (We might also conclude from this that the anthropogenic co2 portion of the atmosphere is one thousandth of a percent)
Mostly because, at present, O2 is about 20% of the atmosphere.
CO2 is significantly less than 1% of the atmosphere. If we double the amount of CO2 in the atmosphere, it will remove some oxygen from the atmosphere, but it will be a small enough fraction of the total oxygen that we won't really notice it.
Also, if I recall my photosynthesis chemistry correctly, the O2 that plants give off isn't from CO2, it's from water...
"From 1991 through 2005, the O2 content of the atmosphere has dropped by 0.00248% (248 per meg) of it's initial amount. The rate is mostly explained by the global combustion of fossil-fuel over this period, although the actual rate is slightly smaller than expected from fossil-fuel alone. The difference evidently reflects a global imballance between photosynthesis and respiration."
Because plants recycle CO2 and produce O2.
Plants use carbon dioxide and give off oxygen. Organisms in all of our oceans produce oxygen. Carbon dioxide is 0.03 per cent of the atmosphere. Oxygen is created faster than it is used by combustion alone.
It is. slowly depleting that's why any ideas about sequestering Co2 are crazy we would not only locking away carbon but our oxygen too.
The plant biomass is increasing in responce to rising Co2 levels and will in time turn most of the Co2 back to carbon and oxygen.
It IS. The amount of oxygen in the atmosphere IS decreasing. It is not much of an issue because there is so much oxygen in the air. Even after the decrease there is plenty available to breathe.
Who said it was't depleting O2?....it certainly is depleting.
It is depleting o2.
http://scrippso2.ucsd.edu/osub2sub-data
If using fossils fuels tends to put more CO2 into the atmosphere, why isn't all that combustion depleting O2?
