Will skeptics realize that current theory is valid when temperatures increases again within two years?

No, denial is a normal human reaction to addiction and threats. It has nothing to do with reality, it interrupts the afflicted person's ability to think logically, and it is not influenced by facts. They will blame scientists and people who believe them, just as they do today, instead of assuming responsibility for their role in what's happening.

The 2008 dip in the forecast is probably due to an assumed volcanic eruption, which of course can't actually be forecasted. The theoretical projections need to be routinely adjusted as actual volcanos do erupt and aerosols temporarily cool global climate.

eric c - Pielke's blog that you refer to concludes in part:

"The IPCC actually has a pretty good track record in its predictions, especially after it dramatically reduced its 1990 prediction." Your supporting evidence contradicts your point!

Pielke makes some potentially useful and valid points about forecasts and verification. He also complains that critics of his points nit pick on one minor point but then try to make the leap to claim that one minor disagreement disproves the larger question he raises. You appear to be trying to use that same tactic. Thanks for the link exposing it.

NASA's 1995 correction was in response to the eruption of Mt. Pinatubo and the observed (and expected) effect of aerosol cooling. NASA's models insert volcanos in random places but then have to be corrected to account for when the real ones do erupt. Is there something about that process that is not clear to you?

Should scientists be able to instead magically predict volcano eruptions accurately in climate projections? With what, a "Magic 8 Ball, Volcano Prediction Edition" perhaps?

Here's what one of the world's leading aerosol scientists has to say about their short-lived cooling effect:

"HEAT CAPACITY, TIME CONSTANT, AND SENSITIVITY OF EARTH'S CLIMATE SYSTEM" by Stephen E. Schwartz, June 2007

http://www.ecd.bnl.gov/steve/pubs/HeatCapacity.pdf

"It should be emphasized that one should not take any comfort with the fact that the aerosols may be negating much of the greenhouse gas forcing--in fact just the opposite."

This recent paper by Schwartz is often pointed to by denialist blogs as evidence that global warming isn't as bad as predicted. Nothing could be further from the truth.

Here's more on Steven Schwartz's expert opinion, based on the problem that CO2 stays in the air 1000+ years and accumulates, while the mitigating aerosol pollutants don't:

http://www.ecd.bnl.gov/news/NationalPost.html

Stephen Schwartz knows as much about the effects of aerosols on climate change as anyone in the world, and he's worried. He believes climate change is so massive an economic issue that we face costs "in the trillions if not quadrillions of dollars." He thinks a Herculean effort and great sacrifice is required to get the world down to zero net increase in carbon dioxide concentrations, an effort he compares to that which the Allies undertook in their all-out war against Nazi Germany and Japan.

James Hansen predicted in 1988 that temperatures would fall in 2008?

Well I guess we won't be seeing any more miracles from the messiah. For the most part he's out of the habit of predicting things that will come true in his life time. Mainly he just says a non-specific disaster may happen if we don't act in the next 10 years.

If it gets hotter or cooler in itself doesn't prove that CO2 is the driving factor (although it the world does warm, AGW from CO2 would look a little more credible, but if the world decends into another little ice age, AGW will be looking a bit rediculous).

You of all people should realise that the world warms a lot for reasons other than CO2. In the 1400's when the Swedish army marched accross the frozen sea, this isn't something that some right wing politicians made up, they really did march on the frozen water and when they got to Denmark, the Danes really did die - the historians are not making this up. The world really was cold back then, despite what the IPCC says. The world didn't warm up then because of CO2 and the best information available suggests that it's role in recent climate change is insignificant.

The problem with global warming is that it is a theory which cannot be tested by experimentation. We can only try to describe what we observe. We can't tinker with the system to test the hypothesis.

So while the global warming theory appears to describe what is happening in the world, there is no "proof" as such.

That being said, I trust the scientific community and it would appear that the general consensus is one that beleives that increasing greenhouse gas concentrations are causing an increase in world temperatures.

But you can certainly understand skeptics, because the theory cannot be properly tested using the scientific method.

I doubt it. I don't think anything will change their minds until something catastrophic happens. If they are like climate skeptics I've known, they will not think twice about dismissing their previous explanations for warming for a whole batch of new ones as the old ones are proven wrong. It doesn't seem to occur to them how disingenuous it is to keep coming up with new explanations every time you get it handed to you by evidence. The creationsists have been doing this sort of thing for 150 years. They remind me of the knight in Monty Python who gets all his arms and legs chopped off and still begs for a fair fight.

It's funny.

I wonder the same thing, only it's more like: "Will the global warming enthusiasts realize that global warming is a hoax when it's still cool in two years?"

The flaw in this theory is that no volcano erupted this year to cause this cooling. It's not caused by a catastrophic event, but the cycle the earth goes through.

The major dispute is far as I am concerned is how much harm might come from the warming. The warming humans have added is not likely to be driving warming. It is simply adding a little warmth to a warming trend and by adding greenhouse gases, it should add moderation in temperatures as well by warming the coldest nights and winter temperatures more. The scam is created by ignoring the obvious benefits and exaggerating the negative consequences. There is also wild speculation from some sources that suggest we are going to warm several degrees which is without merit in my opinion. It could easily begin cooling.

Wow, a made up graph that has a dip approximately where you see a low temperature is proof? Is the dip accruate? What about all the other points on the graph that are wrong?

Oh yea, I forgot. It was on the internet, and it says that it was published in 1988, so it MUST be true.

You know, I wonder how he calculated the little dips and increases in that model. He probably included the small effect from the 11-year solar cycle, but surely you can't model ENSO and the other decadal cycles 20 years in advance?

What really matters is the long-term trend, and Hansen's model nailed that.

*edit* Stefan Rahmstorf at RealClimate corrects the errors made in the Pielke Jr. model analysis linked by eric c here:

http://www.realclimate.org/index.php/archives/2008...

But Pielke Jr's conclusion is "The IPCC actually has a pretty good track record in its predictions".

Maybe try reading your own links next time, eric.

judging by how long it took to get the tobacco companies (and associated politicians, and smokers) to admit the harm from smoking, it wont.

i'm fascinated by the tally between the model dip at 1992 ish and the pintabothingy volcano, was that a coincidence!

My guess would be "NO" nothing is going to do that, but I think I'll go with Jello's answer; people can't predict the future.