Trends

There has been much discussion this past week about the concentration of carbon dioxide in the atmosphere, and the attendant impact of such on climate. Not only has the concentration passed 400 parts per million for the first time in 4.5 million years, but, as concerning, it is continuing to rise at a rate of some 2 parts per million every year. Extrapolating this trend to the end of this century, commentators note that CO2 concentration would be 800 parts per million. Thus, the argument runs, the risk of apocalyptic climate change (warming) is large and growing.

A century and a bit ago, there was a similar alarm sounded over quite a different trend. On July 24, 1881, the New York Times noted that "deprived of their human servitors, the horses would quickly perish; deprived of their equine servitors, the human population in cities - dependent upon their daily food from the outside, and upon the regular flow and reflow of traffic - would soon be in straits of distress". In short, urban dwellers couldn't do without their horses. Such dependency, together with a secular drop in demand for manure as fertilizer (as phosphate substitutes were appearing in the market) produced "The Great Manure Crisis of 1894". The world, according to pundits of the time - who were also extrapolating current trends - was about to drown in manure. But, then, over the next few decades, humans invented automobiles, and, as importantly, a means of making and distributing them in an affordable way to many. The manure crisis was no more.

The point here is not to trivialize greenhouse gas emissions, their impact on climate change, and in turn its impact on humans. This writer's tongue is not firmly in his cheek. The manure crisis was real, at the time, as is the CO2 crisis now. The point is  that innovation has dramatically and frequently intervened at critical points over the centuries to render dangerous trends irrelevant - Malthus would have never imagined in the 18th century how the 21st-century world feeds and clothes as many as it does. Technology keeps improving things, notwithstanding the gloom of the day.