Uncertainty is here to stay, say climatologists

There's no getting around it: the climate is just too damn complex, and computer models, "no matter how powerful, can never give a precise prediction of how greenhouse gases will warm the Earth, according to a new study" (New Scientist) So say a couple of guys who have published their mathematical musing in Science. But this changes nothing.

Those who refuse to accept the reality of anthropogenic climate change will continue to insist we can't act without better data, and those who understand the science will continue to argue that we have enough information to justify acting now.

But for what it's worth, here's the nub of the argument put forth by Gerard Roe and Marcia Baker of the University of Washington in Seattle. It's based on a whole lot of fancy equations that are way beyond most of us:

We have shown that the uncertainty in the climate sensitivity in 2 x CO2 studies is a direct and general result of the fact that the sum of the underlying climate feedbacks is substantially positive.... We are constrained by the inevitable: the more likely a large warming is for a given forcing (i.e., the greater the positive feedbacks), the greater the uncertainty will be in the magnitude of that warming.

So don't get your hopes up:

We do not therefore expect the range presented in the next IPCC report to be greatly different from that in the 2007 report.

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I just don't understand why people think uncertainty is a good reason to postpone action. The thicker the fog, the more you slow down. If you need to wait until you actually see an obstacle in the road before you take your foot off the gas, you're some kind of idiot. It's like thinking that what you don't know can't hurt you...

The whole argument they make is odd. There may be more uncertainty in the
-magnitude- of warming if the warming is greater, but that doesn't mean that the uncertainty in -a given magnitude- won't be less.

For example - If suddenly models predict that warming is doubled and the uncertainty is 50% higher, then the uncertainty of the previous level of warming occurring may actually be less. So if the original modeled level of warming was thought to be bad, there is MORE certainty in this example, that something ought to be done about it, even given the authors conclusions.

I am a former computer guru. Stay out of the field any number of years and you have tack the former on there! That field moves like nothing else!
Here is a quote from above:There's no getting around it: the climate is just too damn complex, and computer models, "no matter how powerful, can never give a precise prediction of how greenhouse gases will warm the Earth, according to a new study"
I beg to differ with this. I remember 10 or 15 years ago where the climate modeling was and the miraculous jumps since then.
With Moore's law at work and computing power going up as fast as it is I think we are going to understand a whole lot more than we can imagine, faster than we thought!
Dave Briggs :~)