Global Warming ping
Excellent article.
As a scientist, we have a name for this. It's called a WAG.
That's a wild-a$$ guess, for those of your in Rio Linda.
Just don't build too close to the coast and dress appropriately for the weather. That should get a person by.
Yup. My electronics engineering training has been virtually no help in my career in semiconductor processing.
Computational sciences have given new life to countless careers that would otherwise have been converted to used car sales.
Thomas Sowell's first job as an economist after graduating from Harvard was working for AT&T making economic predictions, using mathematical models. His boss showed him were the previous models (stacks of punch cards) where kept, so he could use them as a starting point. Young Thomas says "Oh, great, then we can see how well we've done!" His boss's reaction made it clear that he was *never* to bring up that idea again.
Actually, regression analysis allows one to place reliable bounds on the accuracy of a model, like when astronomers say that there is a 1 in 45,000 chance of a certain asteriod striking earth in 2036 (or whatever).
The IPCC seems to be paying homage to notion of error bounds by saying that there is a 90% chance of some {poorly defined unfavorable} event. What the author of this piece is talking about is what is known as validation. Historical data is perfectly good for validating a model, provided you can establish *all* the relevant input parameters and their associated uncertainties. I am personally unimpressed by anything I've read or seen about global warming to date. The alarmist scenarios are just too convenient for the politcal Left.
Ping to read when I'm having trouble sleeping.....
ping
Counterpoint: "We don't have time to wait, we must act now."
Read this small piece from today's Tennessean by Beverly Keel the celebrity columnist for Gore's views yesterday:
http://tennessean.com/apps/pbcs.dll/article?AID=/20070228/NEWS01/702280434
bookmarked
http://en.wikipedia.org/wiki/Chaos_theory
It would seem to me that chaos theory would suggest that it is impossible to predict with any degree of certainty any claims of future global warming specificially due to man. Too many variables, too many assumptions or simplifications/etc. in variables.
I particularly loved these two paragraphs, Which should be self evident to anyone with just a conversant familiarity with the hard sciences:
Almost all semiconductor manufacturing processes occur in closed vessels. This permits the engineers to precisely control the input chemicals (gases) and the pressure, temperature, etc. with high degree of precision and reliability.
Closed systems are also much easier to model as compared to systems open to the atmosphere (that should tell us something already). Computer models are used to inform the engineering team as the design the shape, temperature ramp, flow rates, etc, etc, (i.e. the thermodynamics) of the new reactor.
Nonetheless, despite the fact that 1) the chemical reactions are highly studied, 2) there exists extensive experience with similar reactors, much of it recorded in the open literature, 3) the input gases and materials are of high and known purity, and 4) the process is controlled with incredible precision, the predictions of the models are often wrong, requiring that the reactor be adjusted empirically to produce the desired product with quality and reliability.
There was an article recently by a statistician, who pointed out that use of statistics analysis by amateurs can quickly lead to non-sensical results.
For example, if 3 assumptions are made which are 99% correct, the results can only be correct, significantly less than 99%.
When just a dozen factors are 99% correct, the results are only about 50% reliable.
With climate having dozens, perhaps hundreds of relevant factors, most of which are guessed at or ignored altogether, how reliable can these computer "model predictions" be?
thanks, bfl
... ping
Mark