I wrote the other day about how petroleum will someday run out and commented on how we’re not doing more to develop alternative sources of energy. In response I received the following from a reader, Jay Spivack, which I think may be of interest to readers of this blog, and which I here reproduce, with his permission:

I am a chemist, retired from GE Global Research in Nisakayuna and formerly a chemistry professor at SUNY Coblekill.
You probably have been told that the oxygen we breathe is made by plants. This is true but is only part of the story. As a plant grows it absorbs carbon dioxide from the air and converts it to carbon containing materials (such as wood) and releases the oxygen from the carbon dioxide into the air. However when the plant dies and aerobically rots all that carbon is converted back to carbon dioxide and all the oxygen that was released during its lifetime is removed from the air in that process. Thus a complete life cycle of a plant normally produces no net oxygen.
So where does the oxygen in our atmosphere come from? Well, a small fraction of plants never get to completely aerobically rot. They sink into bogs or are covered by sediment or volcanic ash, etc. This removes their carbon from the usual cycle and leaves the oxygen the plant created in the atmosphere. These buried plants, buried beyond the reach of the atmosphere turn into fossil fuels: oil, coal, peat, natural gas, etc. Thus if this is the only mechanism for making atmospheric oxygen (and it is certainly the dominant mechanism) every molecule of oxygen in the air is matched by a buried carbon atom in fossil fuel. This has two important implications. First, there is a lot fuel we have not found (although it may be that most of it is scattered and hard to get at). Second, if we are smart enough to find it all and burn it we will succeed in using up all the oxygen in the atmosphere! The only reason no one is talking about the fact that not only is carbon dioxide rising but oxygen is also falling is that we have only scratched the surface as yet. There is much much more oxygen than carbon dioxide in the air (21% O2 vs. 0.0381% CO2) so it is easy to notice the CO2 rising but not the O2 falling.
I am not writing this because I am actually worried about using up the oxygen. That would take a long time and a lot of fossil fuel burning. I am writing this to make the point that the process of burning fossil fuels is inherently finite and counter productive. The formation of fossil fuel is essential to maintain the air we breathe and it’s combustion, in just a few years, reverses the natural process that took many millions of years to produce the oxygen we breathe.
The most important technological problem humanity faces is to replace fossil fuel burning with all forms of solar, wind and nuclear energy as soon as possible. Our next president & congress need to make this a priority as high as mobilization for WWII.
I hope I have made this clear. There is much more to the effects of carbon dioxide than “just” global warming, for example the acidification of the oceans.
One more point: this switch in energy usage from fossil fuels to solar/nuclear is the largest business opportunity of all time. If businessmen were more like Edison and less like current CEO’s the USA could strike it rich by doing what we are best at: technological innovation.