One swallow does not make a summer

… neither does one fine day; similarly one day or brief time of happiness does not make a person entirely happy, so wrote Aristotle. It is just happiness that depends on more than a brief moment, but also climate change.

We have had a very bitter December in the United Kingdom and in many parts of Northern Europe. It is not time to think that global warming has reversed or that we are in for another period like the Maunder Minimum on this account. A few years readings do not signify the direction of a changing climate and the reason is simple. Two thirds of the surface of this planet is covered by large amounts of water. We might know a great deal about measuring climate and its variations, and we might be able to suggest algorithms for predicting where the climate is going but we do not have the most important information for our calculations. We do not understand how much energy the sea absorbs and what the effect of this absorption will be on a changing climate.

The sea has a conveyor belt type current which circulates much of the oceans like a continuous mobius band, starting where it ends. The oscillation is governed by sea temperatures. There is plenty of capacity in the sea to absorb heat, but we do not know the effect of this on the sea’s great oscillations and how it will affect the Gulf Stream, the Humboldt and all the other branches of this planet’s great currents.

I have read many articles in which writers, some learned and some ignorant of learning, suggest that global cooling is today’s threat rather than global warming. Perhaps they are right but their suggestion if based on a season’s weather in a particular location, is no more scientific than guessing the lottery numbers or calculating a formula to beat the casino. Others argue that the planet is warming and that remains the view of the majority of those who have studied the case. Despite the snow 2010 will be the warmest or second warmest year on record, as far as the planet is concerned.

Just as one swallow does not make a summer, so one snowfall does not an ice age make.