Climate Change (1) Climate Forecasting

People are saying that climate change is the greatest threat to human life ever experienced. I don’t believe that is true. The greatest threat to life on earth is nuclear war, but more on that in a later post.

Like economic forecasting, climate forecasting is not a true science. The scientific method works by conducting repeatable experiments to test whether a well-defined hypothesis is true or not.

Climate change occurs over long periods of time and affects the whole world, so it is impossible to set up a repeatable experiment to determine if the hypothesis of anthropomorphic climate change is correct.

Climate scientists have to do what economists do. They set up models, with numerous assumptions and equations that approximate the real world to see what results the model produces. The problem is that models are only solvable if there are sufficient restrictive assumptions in place. But the more assumptions that are used, the less the model actually reflects the real world, and therefore the less unreliable the results.

Politicians claim that there is a scientific consensus about climate change, but science does not work by consensus; that’s what politicians try to do. Scientist work by testing well-defined hypotheses with repeatable experiments.
Economists have the same problem. Their models only work if the impose restrictive assumptions that make the models unrealistic. This is why economists disagree about everything.

The world economy and the climate system are both extremely complex, so it is almost impossible to create realistic computer models that reflect their workings accurately. Just as it is impossible to predict the effects of particular economic policies, it is impossible to accurately predict climate change. You can observe trends, but the direction of a trend usually depends on the length of the observation period. It is very difficult to separate the trend from the noise, especially in complex systems, like the weather. And you never know whether a trend will continue, or reverse.

So, we have to be open-minded about climate change. The climate is definitely changing because that is what climate does. Climate is defined as the small changes in the weather that occur over time. However, we cannot be certain whether the changes we observe over time.