The case for AGW is not that the earth is getting warmer. The case, as presented by the IPCC, is that the temperature of the planet is unprecedented, the increase in global temps is accelerating, and that there is no other explanation for it; therefore it must be caused by man. I won’t dwell on the logic of the last part other than to say this brand of logic is also used by those who deny the existence of evolution and promote intelligent design. But let’s look at the first two parts, unprecedented and accelerating temperatures. It’s all about the “hockey stick.”

As late as 1991 the IPCC had a graph showing the earth’s temperature over the last couple thousand years and it included the Medieval Warm Period (900-1300 AD) and the Little Ice Age. Since no direct temperature readings exist climatologists today used proxy data, known facts like a thousand years ago the tree line in European mountain ranges was 2,000 feet higher than today or that settlements and agriculture flourished in Greenland, then disappeared, and graves of those settlers lie under rock-hard permafrost today. And there’s tree ring data.

But over the next decade the MWP and the LIA both disappeared from the IPCC charts in stages giving us a chart showing a couple thousand years of gradual warming with a big increase recently…the blade of the hockey stick. (Anyone who saw Al Gore’s movie will remember the hockey stick.) This, in short became the prime evidence of AGW. The logic is that it is unprecedented, increasing, and no other explanation can be found.

Where did the Medieval Warm Period and the Little Ice Age go? Well, the first step was in 1995 when 1991 IPCC chart was replaced with a 1993 reconstruction made by R.S. Bradley and Climate Research Unit’s (CRU) chief, Phil Jones. It used 1400 AD as its base year very effectively wiping the MWP off the chart. (Yes, this is the same Phil Jones who is at the center of the leaked email controversy.) Then in the 2001 Third Assessment Report (TAR) the MWP simply vanished. Again the cast of characters involved in this “trick” are those at the center of the email controversy. In the emails, “Mike’s Nature trick”, is the trick used by Michael Mann in the pivotal Nature paper co-authored by Jones which used multiple proxies but only where each caused the MWP to disappear. (Mann is also in the center of this and under investigation by his University.)

What is so important about all this is that the individuals who are in the midst of this email controversy are also the individuals who provided the prime “evidence” for AGW. The are the scientists who used “Mike’s Nature trick” to eliminate the Medieval Warm Period, the Little Ice Age, and “hide the decline” that the recent tree ring data were showing. These scientists are the ones who would not provide the raw data they were using for others to evaluate. They conspired to avoid FOI requests. They destroyed data. They are the ones who conspired to keep research results different than their own out of journals.

This is a big deal. If anyone is interested in further reading, and isn’t afraid of graphs and data and jargon, I recommend:

http://climateaudit.org/2009/12/10/ipcc-and-the-trick/ and http://www.americanthinker.com/2009/12/understanding_climategates_hid.html

I’d really like to recommend a new web tool to everyone. It has many uses, but I have just tried it for weather data and it is easy and fun to use.

It is WolframAlpha and can be accessed at http://www.wolframalpha.com On that page is a short, but great introduction to the tool by Stephen Wolfram. Check it out.

While your there put in “mean temperature Napa California” and see what you get. You will see a chart of the mean temp for the current week, but you can select other time periods. Select “all” and it will show you the mean temperature at the Napa airport since the mid 1940′s. The results might surprise you. Now do Saint Helena. (You get Santa Rosa Airport data.) If we are to believe these graphs, maybe we should be moving South.

Clearly you have a full understanding of the science, so let me amplify your comments with the following:

- The models do not take solar activity (read flares, sunspots, magnetic rays) into account.

While that may sound unbelievable, its because there is no known and proven mechanism that can be incorporated into the models.

This is why when I hear pro-AGW folks claim we should only listen to climate scientists, I tend to roll my eyes. Climate models are entirely dependent on the primary research of physicists. Climate modeling is the epitome of a multi-disciplinary field, and legitimate voices are consistently marginalized simply because they aren’t in the “climate modeler” bucket. Pure politics.

- A very similar story is true for cloud cover. There is no accounting in models for cloud dynamics because they are poorly understood, and yet if we assume a world with no clouds, the warming effect attributed to man would be 10 times greater – just due to the lack of clouds.

To say that there is ignorance of important aspects of the drivers of warming is understating the matter in the extreme.

Really appreciate the comment!

I’m pretty sure that the failures of the models are two-fold. First and perhaps most crippling, no matter how complex the models are they are still too simple. CO2 forcing can’t be evaluated independently of the many other GHG’s (especially methane) plus the cooling effects of variable cloud cover and aerosols. The models do an abysmal job of balancing “butterfly-wing” effects with naturally-occurring and man-made damping factors.

Secondly – and perhaps in the long term even more of a hindrance to establishing any predictive value – even the over-simplified models are exquisitely sensitive to starting conditions, which inputs themsleves are non-real-time approximations. How old and how accurate are the data on how many thousands of square miles of rainforest have been clear cut? Did the input data pick up that Soufriere just pumped another 100,000 tons of sulfate aerosols into the atmosphere last week? (Not that it actually did, but I hope you get my point.)

IMO one of the great things about the scientific method is that it works well not just in spite of the pettiness and human failings of the practitioners, but often because of them. Data forgers, frauds and snake-oil salesmen in science are not just subject to peer review, but are also targeted by the jealousies and insecurities of those they share the field with. I would argue that exposure is the first step to transparency, and that fraud is exposed much more quickly in scientific pursuit than it is in, say, business, media or politics. It is also taken more seriously, and hardly ever forgiven.

I agree that there may be sound reasons to make policy for reducing the human carbon footprint, but that controlling GCC is not a very strong one. Reducing the rate of burning fossil fuels alone won’t affect the rate of climate change. Even simultaneously enacting policies to encourage reforestation and to dramatically decrease our dependence on beef won’t do it. Perhaps we should do these things, but not because it will alter the rate of climate change.

I believe AGW is less of a scientific construct than a political one, one designed to generate fear – fear being the thing that most motivates support for controversial policy change. Perhaps we should be arguing for a wall between Science and State with the same fervor our founding fathers had for a wall between Church and State.

As to whether arguments for or against AGW shoult affect what I plant in the vineyard? Well, given that I believe GCC is occurring, and given the uncertainty in what its effects are going to be in my lifetime, I hedged. We chose a marginal location: I have Pinot in the coolest parts of the vineyard, which means we are very late to pick Pinot every year (10/8 this year, for example). I put late-ripening Rhones in the warmest locations – stuff we never pick before November, where ripening becomes dictated by day-length perhaps even more than by temperature. If it warms in my lifetime, I might bud Pinot over to more Rhones. If it cools, I do the opposite. So frankly I don’t give a damn what they do or don’t decide at Copenhagen.

There are a vast number of deniers out there that will profit far more in the short term on a do nothing approach than the East Anglia scientists could ever hope to in their entire lives with a cap and trade system. These guys are under seige and are, as the Nature editorial suggests, only human. This will precipitate hopefully only more transparency and easier access to information to help us make up our own minds.

What chews me up about this is that I’m probably only 60% on the AGW side, but I see the benefits of action far more compelling than the risk of a wait and see approach.

Rant ends.

Andrew

As to your question, if I read it as “should we try to reduce carbon emissions based solely on the evidence for AGW?” I think the answer is clearly no. But if I read it as “is there any reason for us to be trying to reduce our carbon emissions,” well there are plenty of good reasons to reduce our dependence of fossil fuels that have nothing to do with warming.

The key distinction of course is if AGW isn’t the driver of warming that the models predict, our efforts at curbing emissions will have no effect on the warming. It will be a useless in that regard.

If AGW is happening due to CO2 forcing, it will be effective. So it all comes down to if you trust the models, which at this point I don’t see any reason to without first doing a complete and transparent accounting as I mentioned in the post.

Thanks for your readership and for the comment!

I’ve followed your blog for a long time and this is the first time I can say that our opinions diverge.

Down here in south eastern Australia we have had 13 years of below average rainfall. We have just had the hottest six months on record. We are facing another dangerous summer of bushfires, that will hopefully not be as bad as last summer, worse would be unthinkable. And an El Nino, which means down here more hot, dry weather. In short we have a lot to worry about, AGW or natural cycle or whatever. At least I now get my Shiraz and Cab ripe with no problem.

While I agree that we all should be skeptics, I have to ask based on your new position, should we still act on reducing carbon emissions or should we just carry on as we have in the past?

Andrew

Not sure who you are referring to; the pro-warming CRU folks, or the skeptics. Both get funding (one from Governments, the other from Energy companies. Though the emails show CRU was also successfully soliciting money from Exxon.)

In any event, I don’t think I’m the one to be judging people’s motives. In fact, one of the great benefits of science is that despite bad actors and conflicts of interest, the method still produces reliable, verifiable results.

Its that this method has been so utterly corrupted that causes me so much distress. For that, these clowns should pay with their jobs.