Larry,

So tell me if all models predict warming and the observed data fall within the range of predictions starting at some point in the past, do you really believe that the basic trend predicted is likely to be false?

GIGO is well known amongst anyone familiar with software. There is a huge difference however between GIGO and an approximation. It is totally bogus to claim that a model without 100 % accuracy is useless. If you can predict a general trend with an approximation that is far more useful than no prediction at all. Did you read the Sciam link I gave? The simple point is that inaccuracy in the models does not mean the problem they can be dismissed because most predict the same trend and bracket the observed data.

You seem to be claiming that because no model matches the trend in global warming exactly that the global warming trend should not be blaimed on the production of a known greenhouse gas. What is foolish is to assume that somehow a greenhouse gas whose heat trapping properties can be measured in the lab and whose effects on a planetary scale can be predicted for Mars and Venus somehow will conveniently not effect Earth. This makes no sense what so ever without supporting evidence.

The idea that a lack of a total data/model match means the model is likely to be qualitatively wrong as well as quantitatively is poor logic when there is basic underlying science and demonstrated accuracy of related models.

It seems to me the burden of proof should be on producing a validated model which shows how the effects of a greenhouse gas will be negated or limited before the issue can be safely ignored. We have plenty of reason to believe it is an issue. Only wishful thinking to say it isn't as far as I know and have read from others posts.

Heat accumulation is simply heat in minus heat out Larry. It's basic thermo despite republican propaganda otherwise. There are of course complexities to determining the heat out part as you mentioned. What I am uncomfortable with is ignoring a problem we have every reason to believe is real just because we can't predict its exact consequences. This is the equivalent of saying We don't know an impact will hit the US or so let's ignore the problem.

Do you have any real reason to believe a greenhouse gas will not cause global warming? Have you seen any quantitative analysis of the missing simulations you mention to indicate they are large enough to totally dampen out Global warming? You mention most don't include cloud cover. If some do then they are probably included in that analysis I gave the link to above.

Regards,
Mark