Computer Model Fail

From the New Scientist:

What’s special about this latest dip is that the sun is having trouble starting the next solar cycle. The sun began to calm down in late 2007, so no one expected many sunspots in 2008. But computer models predicted that when the spots did return, they would do so in force. Hathaway was reported as thinking the next solar cycle would be a “doozy”: more sunspots, more solar storms and more energy blasted into space. Others predicted that it would be the most active solar cycle on record. The trouble was, no one told the sun.

The first sign that the prediction was wrong came when 2008 turned out to be even calmer than expected. That year, the sun was spot-free 73 per cent of the time, an extreme dip even for a solar minimum. Only the minimum of 1913 was more pronounced, with 85 per cent of that year clear.

As 2009 arrived, solar physicists looked for some action. They didn’t get it. The sun continued to languish until mid-December, when the largest group of sunspots to emerge for several years appeared. Finally, a return to normal? Not really.

Even with the solar cycle finally under way again, the number of sunspots has so far been well below expectations. Something appears to have changed inside the sun, something the models did not predict. But what?

Of course, Anthony Watt has been pointing this out for over two years, even pointing to a discontinuity in the Geomagnetic Average Planetary Index as one sign.

The people who model the sun, and failed, are not bad people.  It is an excercise worth attempting.  It turns out we just don’t know enough about the sun to accurately model its behavior.  Models are only as good as our understanding of the natural processes.  Something to think about with climate models.

8 thoughts on “Computer Model Fail”

  1. This is exactly my gripe with the models, and relying on the models exclusively for proof of CAGW. If we can’t even accurately model the sun, what good are the models? You can’t get the sun right, you certainly can’t get cloud formation right, things like ocean cycles are in a similar state as the sun (we know of certain cycles, but those cycles don’t explain everything), what do you have right? The Earth’s tilt?

  2. To me, this demonstrates exactly what models are good for. They’re good for trying to explain how a complex system works, and to aid in understanding the interactions and internal processes – NOT for predicting how that system will behave in the future.
    IMHO, models are actually most useful when they fail (as in this case) as that shows us what we DON’T know and forces us to investigate more.

  3. Exactly ScepticalGuy,

    That’s been a key point driven home by every course I’ve ever had in mathematical modeling. Its a circle. Come up with a theory, make a model, test your model (preferably with a controlled experiment), when your model fails analyze the data to attempt to figure out why, come up with a new theory, repeat.

  4. Ah, the blinding logic of the sceptic. A model of a physical phenomenon that is not the climate didn’t predict something with 100% accuracy, therefore climate models are all wrong!

    “…relying on the models exclusively for proof of CAGW…”

    What is “CAGW”? Who relies on models exclusively for proof of it?

    “…NOT for predicting how that system will behave in the future”

    What a remarkable misunderstanding of models, and indeed of science generally. All of science is about the construction of models. Some might be computer coded models. Others might be equations written on bits of paper. But they are all models. And they are all trying to predict how the systems being modelled will behave in the future.

  5. As it turns out the way to model the sun is not that complicated, the math was has been used for centuries.
    this site has the details, and some interesting predictions about sunspot activity.
    I’ll wait patiently to hear from Warren and the other more qualified visitors on this.

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