CARBON DIOXIDE - An Essay By Robert M. Wilson

Environmentalists, and lot of other concerned people, believe that an excess of carbon dioxide in the atmosphere is causing global warming. They believe also that global warming will have a lot of serious consequences, like a rise in ocean levels and flooding of large areas near coasts, and migration of deserts northward. They advocate the imposition of limits to reduce the production of carbon dioxide by all of the countries in the world, or at least all of the wealthy ones.

These concerned people are absolutely right in their concerns, but I am not sure that they understand the full consequences of the corrective actions they propose.

When animals, including man, breathe, they inhale oxygen and exhale carbon dioxide. This is because their bodies are Heat Engines. The food (fuel) they eat is consumed (burned) to provide energy (mechanical power) to do things. A by-product of the consumption (combustion) of food, and of breathing, is carbon dioxide.

The atmosphere of the earth is composed mostly of nitrogen and oxygen (about 79% and 21%, respectively), and a few other gases. One would think that all those breathing animals would cause the oxygen gradually to get replaced by carbon dioxide. It doesn’t (or hasn’t so far) because of a clever thing God did when he set up the earth for us.

Plants breathe in carbon dioxide, and breathe out oxygen. This process requires an input of energy, which they get from sunlight. So the plants replenish the oxygen that animals use up. Moreover, God set it up so that the relationship is stable. That is, when it gets out of balance, it tends naturally in the correct direction to set things right.

When the population of animals gets too great, they use up more oxygen than the plants can replace. Because there isn’t enough oxygen to go around, the population of animals decreases. And because there’s lots of carbon dioxide for the plants, they thrive. Then they produce more oxygen for the animals, which can, in their turn, thrive.

Global warming and cooling, on the other hand, aren’t stable. Glaciers, icecaps and snow cover are brilliant white, and reflect back into space a lot of the energy that they receive
from the sun. When the Earth cools, glaciers and icecaps grow, reducing the amount of solar energy that warms the Earth. The colder it gets, the colder it gets.

Similarly, when the Earth warms, the glaciers and icecaps melt, as indeed they are now melting. The Earth retains more of the solar radiation it receives. The warmer it gets, the warmer it gets. At least, until all of the ice is gone.

That’s the way it was until 1769. In that year James Watt invented the steam engine, and launched the Industrial Revolution. One of the animals, man, discovered that he could get a lot more done than he could before.

Up until 1769, a man could go no faster or farther than he could walk. Or than his horse could, if he had one. The only physical work that he could accomplish was what he could do with his own hands, possibly with the help of his wife or his slave or his horse. If he had a lot of money or power, maybe he could organize the work of a lot of men and build a pyramid. (There were a few exceptions to the limitation to muscle power alone, like water mills and sailboats.)

Now, however, man had a machine that could do all that work. He and his comrades quickly invented all sorts of other machines that could do lots more work and go really fast, and far. And generate electric power, that could do work easily and quietly.

The common feature of all of these machines is that they burn fuel, typically wood or coal or oil, and produce carbon dioxide. There are three major exceptions: solar, nuclear, and hydroelectric power. Solar power so far doesn’t seem feasible in large quantity. Nuclear power and hydroelectric power (dams) are opposed by the same people who want to cut back on carbon dioxide. We are now pouring carbon dioxide into the atmosphere far faster than before 1769. Also, we are cutting down trees at a prodigious rate, to clear land and make paper or houses. So we are making more carbon dioxide and the trees are making less oxygen. It seems, therefore, that the animals are getting ahead of the plants.

Carbon dioxide in the atmosphere is measurably increasing. Global warming is the consequence most frequently pointed out. It seems to me that a far more serious consequence lies a little farther in the future: an insufficiency of oxygen to support the growing animal (especially human) population. The number of people, or their carbon dioxide production, or both, will have to decrease. If we don’t bring about the decrease voluntarily, and past experience suggests that we won’t, then Mother Nature will do it for us. The methods chosen by Mother Nature for this purpose are mostly unpleasant: famine, pestilence, earthquake, fire and flood.

The point of all this is that carbon dioxide is produced by doing things. Think of all the things we are doing now that we weren’t doing before 1769. Every family has at least one car, most have two. They don’t walk anywhere; they use the car to go a couple of blocks. (Then they run during their lunch hour to get some exercise.) All houses have central heat and air conditioning. Food is brought from California by big trucks. We don’t wait for fruits and vegetables to get in season any more, we fly them in from wherever they are in season. People take vacations every year, and fly anywhere in the world. We insist on convenience. We choose aluminum over steel, and plastic over wood, for convenience even though the energy demand is much greater. We don’t reuse anything; we throw it away and get another.

That’s the way it is in the wealthy countries, and it’s getting worse. Developing countries like China and India, with a couple of billion people between them, are way behind but going as fast as they can to catch up.

So it seems to me that unless all the countries of the world take much more aggressive action than any are contemplating, the production of carbon dioxide is likely to go on increasing. Perhaps we can help some by increasing the efficiency of our machines. But this just nibbles around the edges. An automobile engine takes in oxygen, nitrogen, and gasoline. It discharges oxygen, nitrogen, water vapor, unburned hydrocarbons, oxides of nitrogen, carbon monoxide, and carbon dioxide. If the engine were perfectly designed and perfectly tuned (which is impossible), it would discharge nitrogen, water vapor, …and carbon dioxide. A Boeing 747 squirts tons of carbon dioxide into the atmosphere. If we decided to use actual horses instead of jet fuel to provide the horsepower needed by the 747, which would be pretty difficult, the breathing of all those horses would produce just as much CO2., probably more.

The inescapable fact is that there is a strong correlation between quality of life and production of carbon dioxide. If we want to stop overloading the atmosphere with carbon dioxide, we are going to have to stop doing things that we want to do. Your neighbor Larry will have to sell his truck and buy a small car with a small engine. Scrap his truck, really, for nobody else would be allowed to use it either. Every incremental decrease is going to cause somebody, like Larry, pain. And he is going to squawk to his Congressman. Just staying even would require causing pain to a lot of people, because of population increase and developing countries. It isn’t going to happen.

It is my opinion that the people on this earth definitely should cut back on the amount of CO2 they produce. Doing so, however, will require making some very hard choices, and persuading people that they will have to cut back sharply on a lot of things that they have been doing, enjoy doing, and believe they have a right to go on doing. That won’t be easy, and I don’t think that many of the people clamoring for controls have thought much about the amount of control that would be necessary and how much people’s lives would be affected.

The problem is a political one as much as it is a scientific one. For me, it falls into the too-hard box. That means, I know what needs to be done, but despair of finding a way to accomplish it.