|MadSci Network: Earth Sciences|
I am taking a meteorology course from a professor at South Dakota School of Mines and Technology. He discussed this topic about 3 weeks ago. His statement was that the amount of O2 in the atmosphere fluctuates by small amounts, but has been relatively stable since our planet first developed an atmosphere. I was surprised at this, since I thought one of the reasons to quit burning rain forests was to keep plants to produce ozone, but I was wrong. When plants die, they decay, and that consumes O2, just as burning does. Plants also use O2 in their metabolism, although they produce more O2 than they burn. So , no, the amount of O2 in the atmosphere is not radically decreasing.
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