Some time ago I noted that, despite the current administration's apparent belief that global warming through greenhouse gases is a recent and unproven theory, the magisterial 1967 edition of the Encyclopedia Britannica had described the phenomenon.
I came across this interesting passage in another textbook:
The water-vapor content of the atmosphere varies and cannot surpass a certain amount. But carbon dioxide has the same absorbing properties as water vapor, and in spite of the fact that it makes up only a very small part of the earth's atmosphere, Arrhenius believes that it has important climatic effects. He concluded that if the quantity of it in the air were doubled the climate would be appreciably warmer, and that if half of it were removed the average temperature of the earth would fall. Chamberlin has shown that there are reasons for believing that the amount of carbon dioxide has varied in long oscillations, and he suggested that this may be the explanation of the ice ages, with intervening warm epochs, which the middle latitudes have experienced.
So far so good, as no serious scientist doubts that the CO2 content of the atmosphere influences the climate. (Arrhenius was a Swedish scientist who lived from 1959 to 1927, and published his theory about the influence of carbon dioxide on climate in 1896.) The question is whether our industrial activities appreciably affect that content. So let's continue with this textbook:
If the effect of carbon dioxide on the climate has been correctly estimated, its production by the recent enormous consumption of coal raises the interesting question whether man at last is not in this way seriously interfering with the cosmic processes. At the present time about 1,000,000,000 tons of coal are mined and burned annually. In order to burn 12 pounds of coal 32 pounds of oxygen are required, and the result of this combustion is 12+32=44 pounds of carbon dioxide. Consequently, by the combustion of coal there is now annually produced by man about 3,670,000,000 tons of carbon dioxide. On referring to the total amount of carbon dioxide now in the air, it is seen that at the present rate of combustion of coal it will be doubled in 800 years. Consequently, there are grounds for believing that modern industry may have sensible climatic effects in a few centuries.
Two observations: first, this is from a source even older than the 1967 Britannica. It comes from the new and revised edition of An Introduction to Astronomy by Forest Ray Moulton (1872-1952), professor of astronomy at the University of Chicago. The new and revised edition from which I quote was published in 1925; the first edition came out in 1905.
Second, coal consumption in the United States is now only 1,120,000,000 tons per year, about the same figure quoted in 1925. Professor Moulton's figure for 1925 is, however, a worldwide figure, and today the world consumes about 6,300,000,000 tons of coal a year, which is about six times the 1925 consumption.
It was warm out today, and it should be warmer tomorrow.
Recent Comments