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Sometimes (read most times) [new scientist] makes me jump up and down with anger!!

For instance this article on [Predicting Chaotic Systems] sent from one of my work buddies. Have a quick read - it’s not very long I promise.

So what’s the problem with it? Well I’m glad you asked!

The analogy given to the problem of predicting chaotic systems is thus:

You cannot predict the exact path a ball will take as it bounces through a pinball machine. But you can predict that the average score will change if the entire machine is tilted.

Which makes sense, but then they go on to say:

Similarly, while we cannot predict the weather in a particular place and on a particular day in 100 years time, we can be sure that on average it will be far warmer if greenhouse gases continue to rise.

Right so read those two statements again and you should stop something inconsistent. Try again, oh all right here it is:

Pinball: tilting table CHANGES average score
Weather: green house gases INCREASE temperature

Right, and what’s the problem with this then? Well we KNOW how to tip a pinball machine to get a better average score, we understand the system. Unfortunately we don’t understand the weather - it’s chaotic you see.

So in the pinball example, we understand the system, we understand what we’ve done to the system and so we can predict the result.

But in the weather example, we DON’T understand the system, we DO understand what we’ve done to it, but that in DOES NOT MEAN that we can predict it. All we’re saying at the moment is: ohh it’s getting hotter isn’t it? Mmmm yes it is! That’s not predicting, it’s some kind of ‘line-of-best-fit’.

Please note that I’m not saying that green houses gases aren’t bad, I’m just trying to make a point about chaotic systems.