"20 years of data" — actually, it's 1000's of years of data. We've collected a lot of ice cores. The timescales for climate change can be very long, but the timescales on which the climate is changing now is very short.

"Google and look for articles" — sorry, I still call your bluff. An article in Time or Newsweek is not the same as a 10-year international effort with an enormous budget and thousands of scientists coming to the consensus that anthropogenic global warming is "unequivocal". I stand by my original comment, which you have not refuted.

Tell me, if all those professional climate scientists tell you you're wrong, and the only ones saying you're right all get paid by an industry whose survival depends on you believing what you do, why do you believe the few and not the many? Could it be that conservatives have such a strong, conditioned disdain for environmentalism that they'll believe in an elaborate hoax perpetrated by a vast, left-wing conspiracy of scientists before anything that comes out of Al Gore's mouth?

Eventually, as the evidence grows, any honest skeptic will have to realize that their resistance to acknowledging the dangers of anthropogenic global warming is no longer tenable. I understand that that point is different for many people. Famous climate skeptic Michael Schermer's flipping point came last year (http://www.sciam.com/article.cfm?chanID=sa006&colID=13&articleID=000B557A-71ED-146C-ADB783414B7F0000). The latest IPCC report, summarizing an enormous undertaking over decades by the world's scientists was published 2 Feb. Where is your flipping point?

If you are an honest broker and not a shill or hack, then answer this question: what would you have to see or read or hear to finally acknowledge global warming as a man-made threat? What evidence would persuade you that you haven't already seen? Or do you believe that it's just impossible, evidence be damned, that increasing the atmospheric CO2 concentration by 40% could possibly have adverse effects on global climate?

As to your three statements…well…so what? What does that have to do with the central point of my post, which is that we do not have nearly enough data to make an informed decision about what to do about what may or may not be happening.

Let me say this. You put a lot o credence in twenty years of data. I do not. I realize that twenty years of data about a system that is millions of years old is like trying to diagnose a disease based on a picosecond's worth of vital signs.

What I and the dissenting scientists are saying is that there are common-sense solutions that don't involve a new global bureaucracy and a set of restrictions that would cripple the industralized world. I am saying that there are quite a few people who are making quite a lot of money drumming up panic. We need to pay more attention to the data and less attention to the politics being played.

Are you claiming it's a misguided hoax or saying that you don't like the proposed solutions?

While I still call your cooling bluff, I do want to reiterate that the whole argument about cooling is as irrelevant as it is illogical. Who cares what the last generation of climate scientists thought before all the satellite data and supercomputers? Those scientists did NOT say "cooling will happen — we have enough data to say so unequivocally." They said that we needed to start a massive campaign to study climate change. They got it. As a result, todays scientists are saying "warming will happen — we now have enough data to say so unequivocally."

Second, you (delibrately?) misinterpreted my post. You wrote:

"First, you say that there is no real dissent that the burning of fossil fuels is the primary reason for global climate change (as I understand the chain of your argument)."

I wrote no such thing. I wrote:

"– There is no disagreement among scientists that CO2 levels are rising…

– There is no disagreement among scientists that the burning of fossil fuels is the primary reason for this…

– There is no disagreement among scientists that increasing CO2 levels will alter global climate…."

No climate scientist, not even the signatories of the letter you linked to, disagrees with any of those points. The link you sent went directly to the other point I quoted, which, again, is a non sequitur. How does the (alleged) lack of absolute proof that man HAS ALREADY changed the climate already in any way challenge the indisputable chain of logic that CO2 is increasing, that we are causing it (the rise in CO2, I mean), and that additional CO2 WILL change the climate? Or, how does arguing that models cannot predict exactly HOW the climate will change alter the conclusion that we will alter it IN SOME WAY in the near future?

First, you say that there is no real dissent that the burning of fossil fuels is the primary reason for global climate change (as I understand the chain of your argument).

Last year, 60 scientists wrote an open letter to the Prime Minister of Canada that said in part, "Global climate changes all the time due to natural causes and the human impact still remains impossible to distinguish from this natural 'noise'". These scientists, who are climatologists and in related fields, believe that we need to spend much more time looking for the actual causes of climate change before we throw a ton of money at it. That's something i've said many times here.

Second, your characterization of global cooling in the 1970s as something confined to just a couple papers by one team of scientists. It was presented as common consensus among scientists. It was headlined in newspapers and magazines. It was taught in schools. It was wrong. You tout new computer models. The same letter I cited before disagrees with you again. It says, "Observational evidence does not support today's computer climate models, so there is little reason to trust model predictions of the future." We now know that the vaunted "hockey stick" model was wrong. Models built on incomplete data – which is all we have still – will never be accurate.

You can find that open letter right here. YOu might also enjoy reading the links here, though I'm sure you will not approve of the source.

You should distinguish between simplistic arguments like "oil money = bad scince" from the bigger argument being made. Almost without exception, all of the (very few) climate skeptics that are actual scientists are a) not climate scientists by training and/or b) funded by big oil. On the other hand, the vast majority of actual climate scientists who say global warming is a problem come from all sorts of funding sources — some are funded by governments, others by big oil (check out the new chief scientist of BP), others by the insurance industry, others by the UN. Being funded by big oil doesn't prove you're wrong, but when the oil companies can't find anyone credible that's not on their payroll to support their position, it's a pretty telling sign.

And you're naive if you think that money motivates climate scientists' conclusions or that some cabal is preventing skeptics from getting funding — the skeptics are swimming in funding; it's the government scientists who have to scramble for ever-scarcer research dollars (although the "let's study it instead of taking action" crowd in Congress HAS helped that some).

And besides, what, exactly, are these skeptics saying that is so persuasive?

– There is no disagreement among scientists that CO2 levels are rising. None. The evidence is indisputable and undisputed. Even the skeptics agree.

– There is no disagreement among scientists that the burning of fossil fuels is the primary reason for this. The evidence is indisputable and undisputed. Again, no actual scientist can dispute this with a straight face.

– There is no disagreement among scientists that increasing CO2 levels will alter global climate. This is just basic physics. There are plenty of uncertainties in the details (hurricanes? the exact amount of sealevel increase?), but the fact that the climate will be disrupted is not in dispute.

You'll notice that most climate "skeptic" arguments are non sequiturs to the above argument. For instance:

"The Earth isn't warming up YET (it's all "heat islands") or, if it is, it hasn't been PROVEN that it's because of humans (it could be the Sun, etc., etc.)." — Well, even if that were true (and, according to the latest consensus, bashed by many as too optimistic, a) is false and there's only a 10% chance that b) true), so what? Just because we can't prove TODAYs warming is CERTAINLY caused by humans, that doesn't somehow prove (or even SUGGEST) that global warming won't be a problem over the next 40 years — it's a complete strawman argument.

"Remember global cooling in the 70s? All of those climate scientists today clearly don't know what they're talking about." You mean a couple of papers by one team of scientists in the infancy of climate science about the impact of aerosols? Before the age of supercomputer climate models and near-universal consensus under the spotlight of intense public scrutiny? That work? So what? This argument is as illogical as it is irrelevent.

But I'm getting far afield here. What are you still on the fence about? What part of the argument I've outlined for believing global warming is a problem do you disagree with?

What actual debate still has you on the fence?