Taking measures to reduce greenhouse gas emissions over the next
decades raises fears among some that  our economy would be adversely
impacted.  Of course, not taking measures, as the UK’s Stern Report argues, could be worse. 

Nonetheless, some nice researchers at Yale conducted a meta-analysis of
the current models for estimating the economic impacts of GGH reduction
measures, identified the seven major assumptions that control 80% of
the differences in estimates, and created a tool to allow anyone to
plug in their own version of these assumptions.

You, too, can play economic advisor: http://www.climate.yale.edu/seeforyourself