The main problem with proxies is that they all contain 'noise' and some may also contain biases, known and unknown. But far enough back in time, that is all there is. Fortunately all that is needed to determine if there is net positive feedback is a temperature trace for a long enough time to average out cyclic variation from random noise and other factors. The temperature trace does not even need to be correct in absolute terms just reasonably accurate in relative terms time-wise.

Much of the Middlebury link is just graphs of NOAA data. It is well referenced so anything can be checked. You will find that it is all valid.

I have never been intimidated by consensus. My knee-jerk question "how can I determine if this is just group-think?”

Realize also that this addresses only the issue of the net effect (or lack there of) of atmospheric carbon dioxide on the average global temperature. Humans have put other GHGs in the atmosphere but I have never seen where anyone tried to quantify their effect on temperature or anything else. Until shown otherwise, I assume that their effect is too small to be detected.

Humanity still faces the issues of peak oil, mercury and radiation from coal, and the need for energy. Eventually, all fossil fuels will be scarce (and I will be long dead). Then, all energy will be distributed by electricity. With enough energy, liquid fuels can be synthesized for transportation. Nuclear breeder reactors (nuclear power plants release less nuclear radiation to the environment than coal plants), using presently available technology can provide all of the energy that humanity will need for millions of years.

Thanks for the links. I welcome finding out what others think. I have yet to find anything technical and valid that refutes what my current perception is but my search is relentless.

Thanks for the comment. I agree that earth is the best "model", yet there is no mention of empirical data (matching or exceeding models, but never mind that).

I'd rather study NOAA data from the NOAA itself and an op-ed piece. But I will look at all your sources – some of whom are well known climate change deniers. Are we to discount the legion of climate scientists that do not agree with these few?

Here are some interesting sources for you:
http://www.climateprogress.org/2008/05/22/should-you-believe-anything-john-christy-or-roy-spencer-say/

http://climateprogress.org/2008/09/03/sorry-deniers-hockey-stick-gets-longer-stronger-earth-hotter-now-than-in-past-2000-years/

http://climateprogress.org/2008/04/28/human-driven-co2-rise-14000-times-faster-than-nature-overwhelming-the-slow-negative-feedbacks/

Really, thanks for the comment, at least you came in citing sources and acting civil.