We know, in the aggregate, that highways and buildings produce a lot of carbon. All those cars and trucks, and all those office towers and shopping malls--with their heating systems, and lighting, and appliances: It all adds up. No doubt. But that highway and that building and that airport? And how they compare? You can’t really appreciate it until you have good data, and, even more important, a good way of visualizing it.
The aim of the Hestia Project, based at Arizona State University, is to make something that’s currently intangible a little more tangible. Taking data from multiple sources--including property filings, and E.P.A. and D.M.V. records--researchers have built up a comprehensive picture of the city environment, starting with Indianapolis. Take a look above. The red bars show commercial buildings, industrial plants, and power facilities. The green swathes are for private residences. And the gray blocks show vehicle emissions at different points of the road network.
Kevin Gurney, an associate professor at A.S.U., says the project helps fill a gap between state-wide estimates of CO2 emissions and audits at the per-building level, and could help city planners improve decision-making--for example, about where to spend more on energy efficiency. "When cities think about improving energy efficiency and lowering emissions, they need to know where in their landscape that will be most effective," he says.
"Efficiency will correlate to building age and quality. Older and poorer neighborhoods are typically more drafty. So, if you are going to have an insulation program, you should focus on those places. That’s where you’ll get most bang for your buck."
He also hopes the maps will increase the public’s sense of shared responsibility for energy and climate. "There is a danger this could lead people to start pointing fingers. But I think it’s more likely they will realize that this isn’t just about SUV drivers, or the power company. It’s part of everyday life. It’s everything around us."
Having started with Indianapolis, the researchers have moved on to Phoenix and Los Angeles. Eventually, they hope to track emissions across the country using the same data sets, most of which are universally available. Gurney says several cities have contacted him asking how they can get involved.
Hestia, which uses about a dozen data sources, is part of a larger project known as Vulcan, which estimates emissions at county and "flyover," national level. Gurney’s larger goal is to remove uncertainty around CO2 emissions, and make the case for action on climate change at different government levels. By providing better data, and making carbon more visible, he hopes we might all take more notice.