In the last 50 years, we've been building the suburbs with a lot of unintended consequences. And I'm going to talk about some of those consequences and just present a whole bunch of really interesting projects that I think give us tremendous reasons to be really optimistic that the big design and development project of the next 50 years is going to be retrofitting suburbia. So whether it's redeveloping dying malls or re-inhabiting dead big-box stores or reconstructing wetlands out of parking lots, I think the fact is the growing number of empty and under-performing, especially retail, sites throughout suburbia gives us actually a tremendous opportunity to take our least-sustainable landscapes right now and convert them into more sustainable places. And in the process, what that allows us to do is to redirect a lot more of our growth back into existing communities that could use a boost, and have the infrastructure in place, instead of continuing to tear down trees and to tear up the green space out at the edges.
So why is this important? I think there are any number of reasons, and I'm just going to not get into detail but mention a few. Just from the perspective of climate change, the average urban dweller in the U.S. has about one-third the carbon footprint of the average suburban dweller, mostly because suburbanites drive a lot more, and living in detached buildings, you have that much more exterior surface to leak energy out of. So strictly from a climate change perspective, the cities are already relatively green. The big opportunity to reduce greenhouse gas emissions is actually in urbanizing the suburbs. All that driving that we've been doing out in the suburbs, we have doubled the amount of miles we drive. It's increased our dependence on foreign oil despite the gains in fuel efficiency. We're just driving so much more; we haven't been able to keep up technologically.