An open invitation

Ahh, thanks for the clarification. I agree that most people don't have a good enough background on this subject, and not much incentive to learn more unfortunately. Yes, the incentives out there now could certainly be more appealing. The carbon goal that has been put forward to get back down to is NOT, most emphatically stated, based on anything models have put out - it's based on paleoclimate records - what has actually happened in the past during glaciations/inter-glaciations and the levels of GHGs that have brought about a stable climate for the past 10,000+ years.
http://arxiv.org/ftp/arxiv/papers/0804/0804.1126.pdf

Sorry dp - it was on the previous page that I was going to link before I decided to save everyone time and go straight to the article. I'm out and about and need to hand my phone off to my son before I have a meltdown on my hands in the restaurant. I'll post that as soon as I get back home. Thanks for the catch!

Here 'tis:
http://arxiv.org/abs/0804.1126
Target atmospheric CO2: Where should humanity aim?
Authors: J. Hansen (1 and 2), M. Sato (1 and 2), P. Kharecha (1 and 2), D. Beerling (3), R. Berner (4), V. Masson-Delmotte (5), M. Pagani (4), M. Raymo (6), D. L. Royer (7), J. C. Zachos (8) ((1) NASA GISS, (2) Columbia Univ. Earth Institute, (3) Univ. Sheffield, (4) Yale Univ., (5) LSCE/IPSL, (6) Boston Univ., (7) Wesleyan Univ., (8) Univ. California Santa Cruz)

(Submitted on 7 Apr 2008 (v1), last revised 15 Oct 2008 (this version, v3))
Comments: 20 pages, 7 figures; final version accepted by Open Atmospheric Science Journal; supporting article separately submitted to arXiv as "Target atmospheric CO2: Supporting material", arxiv:0804.1135
Subjects: Atmospheric and Oceanic Physics (physics.ao-ph)
Journal reference: Open Atmos. Sci. J. (2008), vol. 2, pp. 217-231
DOI: 10.2174/1874282300802010217
Cite as: arXiv:0804.1126v3 [physics.ao-ph]

Paleoclimate data show that climate sensitivity is ~3 deg-C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6 deg-C for doubled CO2 for the range of climate states between glacial conditions and ice-free Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 450 +/- 100 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings.