An icy future

Consider the following recent statement by a columnist in the International Herald Tribune: "When the year began with a two-foot snowfall in Los Angeles, the cause was global warming." Something is going badly wrong in the current debate on climate change. When people start insisting that cold weather is a sign of global warming, then we are not far from the realms of hysteria. There is, in fact, a vast and growing global warming "industry' that thrives on grants from nervous governments and resents any dissension from its view that the world is warming up and that man is responsible. These people take the Marxist-like viewpoint that those who disagree with them or cite contrary evidence (of which there is plenty) are in the pay of the oil companies and are therefore dishonest.

It would be comparatively easy for most of us to adapt to global warming, but much more difficult to adjust to its more terrible opposite, catastrophic global cooling. And of the two, the latter is more likely to occur. These are the facts: there have been 17 ice ages in the last two million years. In other words, 90 percent of this period has been one of bitter cold, as attested by the ice-dominated continents that remain, Greenland and Antarctica, comprising between them a tenth of the world's land surface and bearing six million cubic miles of ice. The previous ice age lasted some 110,000 years and ended about 11,000 years ago. In other words, some 4,000 generations of humans knew of nothing but harsh winds and eternal snows. The apparently "normal'' periods between ice ages, like the present one, have averaged between 8,000 and 12,000 years. In short, the next ice age is overdue. The key question is when it will come. Can space be colonised by a sufficiently large population so that, when the next ice age strikes, it will not threaten the survival of the race? It will be a close run thing. It used to be thought that an ice age would take thousands of years to develop, plenty of time for humanity to establish bridgeheads in space. But sadly this is not the case. In 1979, the Belgian botanist Genevieve Woillard examined the pollen of trees that had stood at the beginning of the last ice age to discover that they had changed from temperate to Arctic within a mere 20 years! Two decades to turn a balmy climate into one as frigid as Lapland. The next ice age will utterly destroy our civilisation. A glacier, in the sinister phrase of Alexander Smith, will "scrape Edinburgh Castle off Edinburgh Rock." In this situation, it is depressing that people who appear to be wholly ignorant about the history of the planet are dominating the debate about the future of our climate. At worst, the global warming industry represents a form of hysterical demagogy. Or it could be just laziness. In the words of Freeman Dyson: "It is much more comfortable for a scientist to run a computer model of the atmosphere in an air-conditioned supercomputer centre than to put on winter clothes and try to keep instruments correctly calibrated in the mud and rain."