I had an interesting discussion with some climate modeling experts over at the 'National Center for Atmospheric Science recently. (Currently summarized here: http://www.climate-lab-book.ac.uk/2012/on-comparing-models-and-observations).
This was about a post apparently comparing models and observations, so I asked about the time period considered suitable for falsifying climate models (apparently 17 years) and how climate models can be verified.
I learnt that reversing a CFD model in time is not mathematically trivial - but is possible - as many papers have been published on this topic. Hence a viable means of proving the validity of GCMs may be reversing time and predicting past climatic events.
Unfortunately, this suggestion was not enthusiastically embraced by the eager modeling 'scientists'!
I pointed out that 'time reversed' temperature models are quite common - for example - medical examiners employ such models to determine the time of death from postmortem temperature measurements.
The modelers argued that not only were the GCMs impossible to validate by comparison with observation (really) but they must also be supplied by the supposed temperature trend ('forcings') in order to make their 'predictions'!
This is similar to telling the medical examiner to determine the time of death, and that by the way it should be exactly 1 am in the morning! I noted that this form of 'forensic' evidence might not seem appropriate, should one ever find oneself in the dock, though a lazy detective might appreciate the convenience of not actually have to prove the facts.
Sadly, this comment was snipped. Such snippings (which are typical of the behavior of the warmist sites) are not really the stuff of openness and honesty, are they?
Much more the behavior of evidence destroying rotten cops - I am not impressed.