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I am really and truly surprised at the debate on global warming. Surely even a back-of-the-envelope calculation as to how difficult it would be to do an accu

I am really and truly surprised at the debate on global warming. Surely even a back-of-the-envelope calculation as to how difficult it would be to do an accurate mathematical model of climate, and the computing power needed to run such a simulation, would show that any prediction based on a computer model at this point is essentially bogus; much less being able to determine whether or not it is caused by man or by natural causes. When you add in the fact that an accurate model of "how oceans work" is decades away (we don't even understand the Gulf Stream at this point) you have to wonder, exactly how can you mathematically model something that you don't understand?

Tichy 19y ago
It seesm unlikely that human civilization has no effect whatsoever, though. Just because we can't calculate something precisely doesn't mean it doesn't exist. There are more phenomena we can't simulate correctly than there are phenomena we can simulate. I guess we can't simulate the weather, either, yet nobody is going around claiming that "hurricanes don't exist".
- JulianMorrison 19y ago
  When a process has homeostatic feedback, it can absorb some change with no result. Also, when a process has a maximum (in the case of CO2, total opacity in its spectral window), then going beyond the maximum has no further effect.
  - Tichy 19y ago
    I wouldn't say my last prayers just yet, either - definitely there are a lot of complex mechanisms at work, and some of them might help to balance the ecosystem. On the other hand there have always been huge climatic changes in the history of earth, so we can't just count on everything staying the same it always was. It didn't work for the dinosaurs, that much is certain. There is no benevolent force that sees to keeping conditions just right for human survival. As for CO2, I also don't know why suddenly all attention is focussed on that. It seems to be just one part of the problem/puzzle.
fauigerzigerk 19y ago
I agree. It's puzzling. I mean there are economists who claim to be able to calculate the cost of climate change over 40 years. I urge everybody who believes them to check the 1 year predictions made by the same people. We're told that if 80 % of scientists agree on something we cannot just dismiss it as nonsense. I would agree with that if even just a few of them had credible methods to simulate complex systems. They don't. Each of them models just a tiny piece of the system and their methods work only within that very narrow context. So what science did the IPCC use to join all those partial models?
- Tichy 19y ago
  That sounds like strawman argumentation: you cite a group of people with bad credentials to denounce all climate researchers. What method would you propose for dealing with climate changes? What about changes in average temperature over the centures. Since you don't believe in any models, would you just ignore that information? Is a very complex simulation even necessary? You don't need to simulate every atom in water to determine it's density in relation to it's temperature, for example.
  - fauigerzigerk 19y ago
    What I'm saying is that there is no scientific basis for making 40 year predictions about complex systems. And I'm not talking about people with bad credentials. Even the best economists' predicitons for a year in advance are pretty bad.

Tichy 19y ago

It seesm unlikely that human civilization has no effect whatsoever, though. Just because we can't calculate something precisely doesn't mean it doesn't exist. There are more phenomena we can't simulate correctly than there are phenomena we can simulate. I guess we can't simulate the weather, either, yet nobody is going around claiming that "hurricanes don't exist".

JulianMorrison 19y ago
When a process has homeostatic feedback, it can absorb some change with no result. Also, when a process has a maximum (in the case of CO2, total opacity in its spectral window), then going beyond the maximum has no further effect.
- Tichy 19y ago
  I wouldn't say my last prayers just yet, either - definitely there are a lot of complex mechanisms at work, and some of them might help to balance the ecosystem. On the other hand there have always been huge climatic changes in the history of earth, so we can't just count on everything staying the same it always was. It didn't work for the dinosaurs, that much is certain. There is no benevolent force that sees to keeping conditions just right for human survival. As for CO2, I also don't know why suddenly all attention is focussed on that. It seems to be just one part of the problem/puzzle.

fauigerzigerk 19y ago

I agree. It's puzzling. I mean there are economists who claim to be able to calculate the cost of climate change over 40 years. I urge everybody who believes them to check the 1 year predictions made by the same people. We're told that if 80 % of scientists agree on something we cannot just dismiss it as nonsense. I would agree with that if even just a few of them had credible methods to simulate complex systems. They don't. Each of them models just a tiny piece of the system and their methods work only within that very narrow context. So what science did the IPCC use to join all those partial models?

Tichy 19y ago
That sounds like strawman argumentation: you cite a group of people with bad credentials to denounce all climate researchers. What method would you propose for dealing with climate changes? What about changes in average temperature over the centures. Since you don't believe in any models, would you just ignore that information? Is a very complex simulation even necessary? You don't need to simulate every atom in water to determine it's density in relation to it's temperature, for example.
- fauigerzigerk 19y ago
  What I'm saying is that there is no scientific basis for making 40 year predictions about complex systems. And I'm not talking about people with bad credentials. Even the best economists' predicitons for a year in advance are pretty bad.