In keeping with the idea of “see for yourself,” I’m posting a link to the entire (or most, anyway) IPCC AR4 Working Group 1 documents below. Included are the first and second order drafts along with comments and reasons for accepting/rejecting each comment.

There’s quite a lot to slog through. If you are one of those with a need for spoonfed opinions, don’t bother. For the rest, it’s an interesting read. Far more information than the media snippets from the Summary for Policy Makers. Anyone notice the difference between the chapter content and the Summary for Policy Makers?

http://ipcc-wg1.ucar.edu/wg1/Comments/wg1-commentFrameset.html

I wish to thank Phil for allowing me to burn some of his bandwidth even though it seems he doesn’t agree with anything I say. I offered to help defray the cost but he politely turned me down so I’m now forced to buy some of his crummy T-shirts I suggest y’all do the same if you haven’t already. He’s dong great work. It’s not his fault he has (*ahem*) blindspots

Cheers,
DAV

There were some comments above about the similarity to religious argument. It’s interesting to compare the AGW/non-AGW blog postings to those between theists/atheists. Ignore the content and just examine the form. For example, try substituting “GW Denier” for “atheist” or “Big Oil Companies” for “Satan.” The atheists marvel at the gullibility of theists while theists are certain atheists are in league with the devil and therefore must be drowned out. Look familiar? Note the subtle shift from “AGW Skeptic” to “GW Denier” or simply “Denier.” Not much different than equating “disbelief in God” with “amoral hedonist” IMO. I am often amazed at the amount of bile this topic generates.

One way to combat this is to examine the issue yourself and try to avoid allowing the opinions of others to become your own by default. Granted, some of the issues require an enormous amount of time to sort out; you may not particularly care enough; and some points may be simply lost due to a lack of the requisite skills. If so, at least try to recognize that and, by all means, avoid echoing secondhand opinions.

For example, I’m no whiz at quantum mechanics. There are certain aspects which I am more or less forced to accept on faith because 1) I trust the sources and 2) I can see (but not necessarily fully understand) the reasoning. Just the same, it would be foolhardy for me to wander into debating those aspects or even voicing my secondhand opinions. The former because I’m hardly qualified which makes the latter a “so what?” matter.

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For those interested in a jumping-off point. This 6 part video (about 50 minutes total) is likely one of the best presentations of the non-AGW issues. It does this without getting into the nitty-gritty one might encounter at say ClimateAudit. It’s a video so don’t expect any references. Think of it as an overview that should be used to familiarize yourself with the major points and guide further research topics.

The “further research” part is the most important. It’s really the only path to a valid opinion. Of course, if you don’t have the time, inclination nor expertise and want to hold a “so what?”-valued opinion, be my guest.

Video on YouTube:
playlist: http://www.youtube.com/view_play_list?p=4506A18E60798509
Haven’t tried it so I don’t know if it works.

Part one: http://www.youtube.com/watch?v=-9Qp5bxrp-c
Part one will lead you to the other parts. The parts are really one continuous video and sometime stop in midsentece so try the playlist link first.

There are deeper investigations into the video’s points at http://www.climateaudit.org with http://www.realclimate.org in particular taking the opposite view(s). Interestingly, ClimateAudit links to opposing view but this is rarely reciprocated. It’s the AGW proponents style to pretend there are no critics but, for whatever reason, they are find themselves forced to address criticisms. Amusing.

1) “Learning Bayesian Networks,” 2004, Prentice Hall (Artificial Intelligence Series)
2) “Probabilistic Reasoning in Expert Systems: Theory and Algorithms,” 1990, John Wiley and Sons

The latter provides more in-depth coverage IMO but is no longer in print and hard to find. I believe there are some copies available on either e-Bay or Amazon Used/New.

(d) and (e) in the above should have read:

d) are there any conditional IN-dependencies between GHG and other variables?
e) what are the dependencies?

Generally, establishing (e) before (d) can be a real timesaver.

You’ve asked a question but the question implies admitting more than one assumption. In the legal world that’s known as a wife-beating question. Before I proceed answer the following:

1) did GHG indeed increase 50ppm in the last 10 years or even 1990-2000?
2) specifically which ones and how much of each?
3) how much of any increase was anthropogenic contribution?
4) how do you separate any anthropogenic contribution from the others?
5) how strong is any correlation between each contribution and the temperature?
6) are there any other possible causes of temperature rise?
7) if so, how do you separate them?

To answer (5) you may need to ascertain the following:
a) is there any time when there has been a temperature rise that preceded a GHG increase?
b) are the concentrations and temperature cyclic?
c) if so, how well do the periods and amplitudes correlate?
d) are there any conditional dependencies between GHG and other variables?
e) what are the independencies?

If you intend to use statistical analysis as a basis for establishing cause you need to proceed with caution. There is an oft repeated maxim in statistics, “correlation does not mean causation,” that predates the 20th century and expresses a lot of truth. It addresses an abuse of statistics that continues through today. However, that doesn’t mean statistics can’t be used to establish causality. For starters I recommend “Causality: Models, Reasoning, and Inference” by Judea Pearl, 2000, Cambridge University Press. It even describes the IC* algorithm that can be used to automate the discovery of causation.

But, what the hey? Why bother with all of that bo-oring, humdrum work trying to answer the above when you can have your opinions spoonfed to ya by blogs and the media? Lately, I find myself coming to the conclusion that many soft sciences are conducted primarily in the media. What other reason could there be to have press releases precede the presentation and discussion of papers? I mean other than preloading the dice for the next send-more-money toss? And then people like Phil wonder and complain about the public’s disaffection with science.