Raisan Cain –
>> Once again the difference between an engineer and a scientist. Engineers understand that the assumptions of the scientists are never true in the real world. <<
No, here is the difference: Engineers think that they know everything about everything – and the “proof” that they are all-knowing is the fact that they are engineers.
It is a perfect closed system. Of course, it is also total Bullshlt.
Last time I asked a similar question, I was under the impression that they assume deterministic. In fact, My large criticism is that they were not treating this like a statistical problem and that they were not fully accounting for the variability.
That was years ago, so I may be wrong, but I found it odd that they were discussing a model with so many unknowns and so many sources of variability as if it were a deterministic model.
Edit:
This is what started my skepticism of AGW. They have models running out to 100 years in the future and their error bars are staying relatively close. In any statistical modeling I have done, the error bars will quickly shoot off to infinity and negative infinity. They are talking about being able to predict the future warming within standard deviation of less than 1.5 degrees, 100 years in the future. They certainly did not assume a stochastic model to get that.
Graphic,
I agree. That is why I have a job. I hear the physicists making claims that they don't need no stinkin statistics.
Once again the difference between an engineer and a scientist. Engineers understand that the assumptions of the scientists are never true in the real world.
These scientists in the AGW realm, keep wondering why the world doesn't act like their models and why they are missing heat.
Gary F,
I have worked with engineers and scientists. If you think that engineers are more arrogant than scientists, then I am certain that you have not worked with enough scientists.
They were still making their minds up last April: http://www.rmets.org/events/should-weath...
Remind me, when was the science settled again?
In my experience, ideas always start off as being linear and deterministic. Maths is very helpful at this point. Think of Ohm's Law: V=IR (V=voltage, I=current and R=resistance). However, it is not long before you discover that no resistor is actually linear. When you put current through them they warm up. Warming a resistor (usually) increases its resistance. Later on, you realise that conductors above absolute zero temperature also generate thermal noise. At low powers that can swamp any simple prediction based simply on Ohm's Law - even if you satisfactorily account for the warming.
All real systems are non-linear and are subject to "noise" or random events.
In the case of the climate, we were told that tropical storms could be started by a butterfly flapping its wings on the other side of the world. Do the IPCC know the location of every butterfly, I wonder?
My understanding of the climate predictions from the models is that they are rather like rolling a dice a number of times and noting the results. This produces a "scenario" i.e. what could happen, and not a prediction. When you roll the dice in anger you will probably get a different result.
The temperature record does not contain a stochastic trend. It autocorrelates, and has a unit root.
Geologists in the petroleum industry apparently had issued dealing with engineers. My school tried to bridge the gap primarily with degrees in geological engineering. I went to the humble South Dakota School of Mines and Technology. Personally, I would expect it to be both. It probably started out as deterministic and evolved from there. I'm no expert in models though obviously.
Climate models are based on assumptions of what climate science does know with the addition of "assumed" outcomes based on what they think they know. The only answer to your question is that they are stochastic. They are "computer games"!
GIGO garbage in garbage out . they are fake and people want to base policies on them .
It would probably help to read this first: http://www.slideshare.net/sohail40/deterministic-vs-stochastic
And this is a little more detailed but I found it very interesting: http://www.scienceheresy.com/2011_03/chaoticorrandom/ICCOR.pdf
You could answer one or the other (or both!?) but it would be great if you also added some personal insight. Thanks.
