When the issue is your own survival, I don't see how you can be "too pure." Saying it better than I could, here are three quotes from a New Yorker (11/20/06) article on climate change and ocean acidification caused by carbon dioxide emissions:
"Being conservative, let's say it's a million species that live in and around coral....at the moment you'd have to say that a million different species are under threat
[from ocean acidification caused by CO2 emissions, in coral reefs alone]."
--Ove Hoegh-Guldberg, oceanographer at the University of Queensland
"You could have food chains collapse. and fisheries ultimately with them, because most of the fish we get from the ocean are at the end of long food chains.You probably will see shifts in favor of invertebrates, or the reign of jellyfish....The risk is that at the end we will have the rise of slime."
--Thomas Lovejoy, Heinz Center for Science, Economics, and the Environment
"And they said, 'O.K., what's the appropriate [CO2] emissions target?' And I said, 'Zero.' If you're talking about mugging little old ladies, you don't say, 'What's our target for the rate of mugging little old ladies?' You say, 'Mugging little old ladies is bad, and we're going to try to eliminate it' .... I think we need to eventually come around to looking at carbon-dioxide emissions the same way."
--Ken Caldeira, Carnegie Institution, Stanford University