Here's Dr. Goklany's summary of what different policies can accomplish:
Halting climate change would reduce cumulative mortality from various climate-sensitive threats, namely, hunger, malaria, and coastal flooding, by 4–10 percent in 2085, while increasing populations at risk from water stress and possibly worsening matters for biodiversity. But according to cost information from the U.N. Millennium Program and the I.P.C.C., measures focused specifically on reducing vulnerability to these threats would reduce cumulative mortality from these risks by 50–75 percent at a fraction of the cost of reducing greenhouse gases (GHGs). Simultaneously, such measures would reduce major hurdles to the developing world's sustainable economic development, the lack of which is why it is most vulnerable to climate change.
Bottom line: the best way to deal with the worst possible effects of global warming is to improve our technology and increase our wealth -- not to handicap our economy with draconian measures typically advocated by environmental extremists.