Expert: Jayendra Upadhye - 7/21/2004

Question
 Does our o-zone layer hold the oxygen around the planet?
   
          Meaning if the o-zone was to completly deteriorate would our oxygen supply float out into the outer space and constrict are lungs to make it harder to breath.  

Answer
Hi Sara,
No! Its is plain old gravity!
Meaning that all the gases (including oxygen and even the ozone) are "bound" to the earth by the "tether" of gravity.
So much so that even the particulate radiation from the sun (the solar wind which is a stream of high speed charged particles), is unable to knock it free.
   Of course the earth's magnetic field deflects much of these particles into the van allen belts, and from there drains them into the polar auroae.

Secondly even if all oxygen were to be suddenly gone, our lungs would not "constrict"! Because 70% of the "air" we breath in and out is NITROGEN, which we dont use anyway!
Ofcourse we would all die in such a catastrophic circumstance.
[Sara as i love to digress..always..It would be nice for you to look up "partial pressure" in your books or library or the web.There is a law for partial pressures of gases in gaseous mixtures such as air]. This law would simply bring atmospheric pressure down by the value of the partial pressure of oxygen at Standard Temperature and Pressure (STP)!

The ozone layer doesnot "keep" the oxygen from floating away, but "saves" us daily from the blast of deadly ultraviolet rays from the sun. these are absorbed by this layer sufficiently to prevent us all from getting skin cancer, and eventually dying from it.

Jayen