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Tracking A City’s Emissions, Building by Building

Scientists at Arizona State University have announced a new computer simulation that displays a city’s greenhouse-gas emissions in unprecedented detail, showing how much heat-trapping carbon dioxide individual buildings and highways generate.

The model, known as Hestia (after the Greek goddess of the hearth), and described in a paper in the October 9 issue of Environmental Science and Technologycould give cities a much better handle on how to reduce their emissions most efficiently.

Quantification of fossil fuel CO2 emissions in Indianapolis.
Click image to enlarge. 
Credit: Bedrich Benes & Michel Abdul-Massih/Purdue University.

The idea is that while cities might be able to guess at where their CO2 emissions mostly come from, it’s more useful to know precisely where the hotspots are — a neighborhood of older houses, for example, or a handful of energy-wasting factories, or a frequently snarled intersection or merge point on a highway. By concentrating on these, a city could make significant improvements in its overall emissions picture with relative ease.

 “We want to help them get the greatest reductions per dollar, the biggest bang for the buck,” said project leader Kevin Gurney, of Arizona State University.

This isn’t the first attempt to quantify local emissions though, Gurney said. “Cities do measure their carbon footprint, but each one uses its own method. Some of them are good, some not so good.” Emissions estimates that cover larger areas exist, but they aren’t all that useful as guides to targeted reductions. 

In fact, Gurney’s group at Arizona State has already created one of these coarse-grained emissions inventories. Called Vulcan, it estimates and maps major CO2 sources in the U.S. down to the county level, including major power plants, highways and big, concentrated sources of emissions from the burning of coal, oil and gas. “Vulcan,” Gurney said, “gets us down to the county level.”

The Hestia project relies on Vulcan’s county-level information, but draws on all sorts of finer-scale data to pinpoint exactly where emissions are coming from. “For buildings, we mine tax records, which gives us a surprising amount of information, including the square footage, the height, how old the building is, what fuel it uses for heating, and more,” Gurney said.

Then he and his team run individual building-energy models designed for estimating heating and air-conditioning needs, to figure out how much energy and of what kind, a specific structure uses. “We don’t know how much glass is in each building,” Gurney said, which is pertinent to energy efficiency, “but we can use Department of Energy regional survey data on average pane thickness on retail buildings, say, of a certain size.”

Quantification of fossil fuel CO2 emissions in Maricopa County, AZ.
Click image to enlarge.
Credit: Semih Yildiz/ASU.  

For roadways the team looks not at total traffic per day on a city’s highways, but at the hour-by-hour statistics for specific stretches of road that municipalities gather to monitor traffic flow. As with the building analysis, Gurney said, “it’s a combination of leveraging what we already know from Vulcan and then adding more detailed information from other sources. We know where everything is.”

The process is clearly very labor-intensive, and so far, the Hestia team has only completed a map for Indianapolis, although maps for Los Angeles and Phoenix are nearing completion as well, and the project will eventually cover hundreds of metropolitan areas. “We’ve had good reaction from the cities we’ve worked with so far,” Gurney said, “but the concept is coming from out of far left field, so they aren’t quite sure how they’ll use all of the data yet.”

He doesn’t think it will take long, however. Mitigating climate change feels like a national problem, too overwhelming for a local government to deal with, Gurney said. “If we can get it down to things that look familiar — a house, a power plant, a commercial building — cities can start addressing it more effectively.“

Gurney even sees the emissions reductions Hestia might help accomplish as a kind of marketing tool. “It’s a great way to sell a city,” he said. Everyone’s fighting for businesses, jobs. Lowering carbon emissions is a way to show that a city is progressive about energy efficiency and fighting pollution.”

Related Coverage 
City Temps May Soar from Urbanization, Global Warming
Hold Your Rejoicing About Those Falling CO2 Emissions
Exploring the New EPA Greenhouse Gas Emissions Database

Comments

By mememine69 (54434)
on October 9th, 2012

The voters of the world have full consensus that the “crisis” was an exaggeration, not a hoax and further CO2 threats to the voter is just what Romneycon wants.
*Occupywallstreet does not even mention CO2 in its list of demands because of the bank-funded carbon trading stock markets run by corporations.
*Obama has not mentioned the crisis in the last two State of the Unions addresses.
*Julian Assange is of course a climate change denier.
*Canada killed Y2Kyoto with a freely elected climate change denying prime minister and nobody cared, especially the millions of scientists warning us of unstoppable warming (a comet hit).
Meanwhile, the entire world of SCIENCE, lazy copy and paste journalism and Liberal progressivism had allowed bank-funded and corporate-run “CARBON TRADING STOCK MARKETS”(ruled by trustworthy politicians) to trump the UN’s and entire world’s efforts into 3rd world fresh water relief, starvation rescue and 3rd world education for just over 26 years of insane attempts at climate CONTROL.
Science has never said it will happen, only might happen despite being at the brink of unstoppable warming.  Not one single IPCC warning is without “maybes”. Help my planet is on fire maybe? If science just said it will happen, not just might happen, the former believer voters would return, maybe.

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