The other day, someone asked me what I thought might have caused global warming, if it is not anthropogenic greenhouse gas emissions. Flippantly, I said I thought that it was probably the development of the computer.

When we look around the world, convincing evidence of a rapidly changing climate is rather difficult to find. The historic temperature record endorsed by the IPPC indicates only a 0.6 ° C increase in temperature during the 20^th century; hardly perceptible without a very sensitive thermometer. Most of our fears about climate change are actually based on predictions about what could happen in the future, not what has already happened, or even what is happening at the moment. So where does information about the climate come from?

It is tempting to think of climate scientists as hardy, open-air types, who bestride the globe fearlessly traversing Antarctic glaciers or sailing the oceans to make observations that will unlock the secrets of the natural world. But these are merely the foot soldiers of the discipline. The cutting edge research, which we so often hear about in the media, is undertaken in far more prosaic circumstances; in cosy offices sitting in front of computers which process arcane statistical procedures in an effort to make sense of observations that reveal only tiny variations in the data. Continue reading »