On Sat, Jun 8, 2013 at 1:52 PM, David Lewis <[email protected]> wrote:
> > > I'm one of those who tend to believe civilization can only go so far down > a path of thoughtless interference with the planetary systems. I haven't > tried to assemble anything like a case that might convince a scientist. > > There have been some reasonable scientific efforts to establish the limits of interference. The 2C, 4C, and 350 ppm targets are all based on what I would call plausible SWAGs or one or two step estimations that are tied to models of reality (not just arbitrary numbers). A more sophisticated and multidimensional approach was attempted by Rockstrom et al. See http://www.environment.arizona.edu/files/env/profiles/liverman/rockstrom-etc-liverman-2009-nature.pdf http://www.nature.com/nature/journal/v461/n7263/full/461472a.html the full text is at A safe operating space for humanity *Nature* *461*, 472-475 (24 September 2009) | doi:10.1038/461472a; Published online 23 September 2009 See associated Correspondence: Cribb, Nature 476, 282 (August 2011)<http://www.nature.com/uidfinder/10.1038/476282b> Johan Rockström1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,2 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a2>, Will Steffen1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,3 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a3>, Kevin Noone1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,4 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a4>, Åsa Persson1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,2 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a2>, F. Stuart Chapin, III5<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a5>, Eric F. Lambin6<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a6>, Timothy M. Lenton7<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a7>, Marten Scheffer8<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a8>, Carl Folke1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,9 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a9>, Hans Joachim Schellnhuber10<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a10> ,11 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a11>, Björn Nykvist1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,2 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a2>, Cynthia A. de Wit4<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a4>, Terry Hughes12<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a12>, Sander van der Leeuw13<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a13>, Henning Rodhe14<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a14>, Sverker Sörlin1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,15 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a15>, Peter K. Snyder16<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a16>, Robert Costanza1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,17 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a17>, Uno Svedin1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1>, Malin Falkenmark1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,18 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a18>, Louise Karlberg1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,2 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a2>, Robert W. Corell19<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a19>, Victoria J. Fabry20<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a20>, James Hansen21<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a21>, Brian Walker1<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a1> ,22 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a22>, Diana Liverman23<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a23> ,24 <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a24>, Katherine Richardson25<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a25>, Paul Crutzen26<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a26> & Jonathan A. Foley27<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#a27> Topof page<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#top> Abstract Identifying and quantifying planetary boundaries that must not be transgressed could help prevent human activities from causing unacceptable environmental change, argue Johan Rockström and colleagues. - New approach proposed for defining preconditions for human development - Crossing certain biophysical thresholds could have disastrous consequences for humanity - Three of nine interlinked planetary boundaries have already been overstepped Although Earth has undergone many periods of significant environmental change, the planet's environment has been unusually stable for the past 10,000 years1, <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#B1> 2, <http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#B2>3<http://www.nature.com/nature/journal/v461/n7263/full/461472a.html#B3>. This period of stability — known to geologists as the Holocene — has seen human civilizations arise, develop and thrive. > > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
