We know by now that the climate is changing and at a terrifyingly rapid rate. This can, and most probably will, have dramatic consequences for the planet. Yet there are still people who actively deny the situation, and quite frequently pour scorn on the predictions made by climate scientists as to what the future may look like. So just how reliable are the climate models?
Well, firstly it needs to be made clear that when people talk of “climate models”, they may be referring to any number of different predictions, from those looking at air temperatures or ground surface temperatures to those looking at sea surface temperatures or carbon dioxide concentrations. All of these have different parameters and alternative factors that influence how they run and how they could be thrown off. Not to mention that sometimes you need to combine models and factors to increase their predictability.
But when you start breaking it down, many studies have shown the massive predictive ability that climate models can achieve. Writing in The Guardian, Dr John Abraham, who is a professor of thermal science at the University of St. Thomas, discusses one of his papers published in the journal Ocean Sciences. After looking at what warming actually occurred and then building a model to see if he could predict the effects, the results were astonishingly close.
“In my mind, this agreement is the strongest vindication of the models ever found, and in fact, in our study we suggest that matches between climate models and ocean warming should be a major test of the models,” writes Dr Abraham. Another common misconception is that models tend to be biased towards exaggerating the effects of climate, although the error bars within models do go either way. In fact, it has actually been found that the Intergovernmental Panel on Climate Change (IPCC) models, the ones used by the United Nations, are more likely to underestimate the effects of climate, something which was again shown earlier this week.
Another area of confusion comes down to the difference between weather and climate. While you might not be able to predict with much accuracy what the weather will be doing in a week’s time, climate is weather averaged over time. So, for example, you may not be able to predict whether an individual coin toss will be heads or tails, but you can predict the statistical result over a large number of tosses. While you may not be able to say with certainty whether it will be cloudy in a few days, you can take an average of temperature and rainfall over the entire region.
So perhaps we should be taking the climate models with a pinch of salt, but only because things may be worse than they predict.