Beginning in the early 1970s I began to hear claims of anthropogenic climate change. In those days the claim was not just of generic climate change but claims of climate warming. I was even then astonished by the uncritical affirmation of this theory and was from the outset highly skeptical of this viewpoint for some very specific reasons.
The climate of the earth is controlled by gigantic natural forces far beyond the influence of any man, group of men. or indeed of all men. Rather than just asserting these vast natural forces it is important to lay them out for examination as well.
The earth was formed about 4.5 billion years ago in the huge disc of debris that orbited around the very young sun. It was formed by collisions of asteroids and comets that lasted millions of years. At the earliest period the earth had no oxygen in the atmosphere at all and the surface was entirely molten lava. Surface temperatures probably exceeded 5kF. With radioactive decay the temperature of the surface gradually cooled. In the late accretion phase asteroids brought in water in sufficient quantities to form the oceans we see today.
The first contributor to climate on earth is the sun and extraterrestrial impact events. If solar output increases only slightly the earth will broil. If solar output decreases only slightly the earth will freeze. This can at least partially be observed as climate tends to vary with the solar cycle of approximately eleven years. Impact events have caused vast changes in climate and major extinctions. Today it is believed that even the moon is a result of an early impact event, and its formation and orbit over billions of years has tended to regulate climate on earth by stabilizing the tilt of the earth on its axis and lengthening the period of precession to about 24k years. This influences climate on earth greatly because land masses and oceans are not evenly distributed on the planet. There is more land mass in the northern hemisphere and more ocean in the southern hemisphere.
Another extraterrestrial factor also regulates climate on earth. Over lengthy periods of time of about 400k years the shape of earth's orbit changes. Sometimes it is more circular and sometimes it is more elliptical. This is thought to be caused by the gravitational influence of Venus and Jupiter. A more circular orbit provides for milder climates while an elliptical orbit produces hotter summers and colder winters.
In short time frames the biomass of the planet sequesters carbon and in long time frames the earth itself sequesters carbon. Decaying organic material is washed off the land masses and is deposited in the oceans. The thick layer of decaying organic material covering the ocean floor of basalt is drawn under continental plates of granite and recooked by the earth to emerge in volcanic eruptions with releases of prodigious quantities of carbon dioxide and other toxic gases. Additionally, in peat deposits and from ocean floors the earth frequently releases large quantities of methane. In other areas biomass from the surface is trapped deep in the earth and over lengthy periods of time becomes deposits of coal, natural gas, and petroleum.
It cannot be emphasized enough that without a very hot solid core surrounded by liquid iron the earth would not have a magnetic field. Without a magnetic field the solar wind would blow the atmosphere off the planet, the oceans would evaporate, and the water vapor would escape into space. So the biomass of the planet and plate tectonics regulate the carbon cycle on earth. With all of these natural factors in play the carbon dioxide and oxygen content of the atmosphere has varied widely over billions of years without any input from man at all. Oceans have been both significantly lower and higher than they are today. Temperatures have varied greatly. At times the earth has been almost entirely sub-tropical or tropical while at other times the earth has been covered with glaciers all the way to the equator. The notion that man in his grandeur and power can cause the oceans to recede is absurd.
The activities of man are two fold. On the one hand man liberates large amounts of carbon in the form of coal, natural gas, and petroleum. On the other hand man sequesters carbon in many of his activities. Man sequesters carbon over long periods of time in building materials, asphalt, rubber, plastics, utility poles, and thousands of other products.
While it is easy to measure the amount of carbon that man liberates, it is very difficult to measure the amount of carbon that man sequesters. Moreover it is difficult to measure both the amount of carbon which the earth liberates and the amount of carbon which the earth sequesters. The efforts aimed at measuring this have proved unproductive. As it happens, if one measures carbon liberated and subtracts carbon sequestered (both by man and by nature) there is a problem. The difference should appear as an increase of carbon dioxide in the atmosphere, but this does not happen. What happens is that as much as 25% of the liberated carbon has somehow disappeared. It has not really disappeared, rather it has been sequestered somehow that we have been unable to determine.
Today the earth is in a terminal phase of de-glaciation. It has been warming for the most part since the end of the little ice age. The next major phase of climate change will probably be global cooling leading into a new period of glaciation. This change may take tens of thousands of years or perhaps even hundreds of thousands of years.
The end result of this kind of examination will reach an inescapable conclusion that the natural forces controlling the carbon cycle render any contribution by man as statistically insignificant. Man is much less important in the grand scheme of things than many are willing to admit. As much as he may try, man will never usher in an utopia.
