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Re: Re: Global Circulation Model Confirmation Criteria

I love the "statistical" aspect of GCMs.

You can't report what is going to happen next year, but you can report what is going to happen on average over the next 30 years.

They don't match what has happened in the past except as an average of the past data.

I just keep thinking of a statement I heard a long time ago. If you want to predict what is going to happen in June in January, your best bet is to check the Farmers almanac.

I don't know how the FA is compiled, but at a guess it would be a compilation of past experience or colloquially the Average.

Do we design heat transfer system using the "average". Oops, we do, but the average we use for heat transfer is more readily quantifiable, and of an entirely different nature. It is not an average over several tens of years, but the average over several tens of centimeters.

The temperature at any given point will likely match the prediction in the model.

The GCM use the same kind of averages within the model. Only their cross sections aren't 10s of centimeters but 10s of thousands of kms cubed (yes I know volume is not a cross section but at the same time it is).

Isn't 30 years about the same period as the Pacific Decadal Oscillation?

I am fairly sure that I would have been fired from the project if I were on it. Rocking the boat does not keep your job.


Re: Re: Re: Global Circulation Model Confirmation Criteria


NASA is sending more vehicles out to the planets. Planning such missions, which typically use gravitation assist type orbits requires us to model the solar system accurately.

Would we send out a mission if the model needed 30 years to provide us an average to let us know where the destination "might" be?

What would be our chance of success.

The three body problem is complex, but it is infinitely less complex than an eco system.