The hysteria over global warming continues to obscure the broader issue of sustainability. Though, in a 'rising tide lifts all boats' sort of way, it may still be a good thing, I still worry that the broader point is getting missed as most people try to sort out the global warming debate.
Since I haven't posted in a while, let me summarize my view of climate change. Adding carbon dioxide to the atmosphere in at the current rate (or anything like it) will cause the planet to keep more of the sun's energy than it radiates. The temperature of the planet WILL rise. This is pretty basic physics and thermodynamics. In the short term, the dynamic systems of the biosphere will adjust (and have been doing so for 100 years), and we won't see many effects. However, virtually every biological system that has been stressed in a similar manner has snapped at some point. We see this in small systems as well as the climate record in response to other changes. What happens next is unclear, it may start snowing more for all we know, but it will probably cause a global crisis.
My bigger point is that we need to take some action and move on. Carbon dioxide emissions are not the only environmental threat that has the potential to cause global instability. There are more out there. Fresh water is a big one you here about. Simply running out of fossil fuels is an issue that will get solved by alternative energy solutions. Environmental contamination may not cause a singular crisis, but it may be a severe burden that opens the door for something else like the next pandemic.
Sustainability is broad philosophy that will help curb the effects of most of these. If every process can account for every input and output, then most of these problems are solved and we can get back to dealing with the political and social issues.
I bring this up again because I just read an article about an issue I hadn't thought of that fall right into this line of thinking: peak phosphorous.
http://www.foreignpolicy.com/articles/2010/04/20/peak_phosphorus