A high-resolution, interactive map of US carbon dioxide emissions from fossil fuels produced by a new analytic system has revealed that the actual geographic intensity of CO2 emissions is quite different than perceived by many. Researchers have been attributing too many emissions to the northeastern US, for example, while the new maps and system indicate that the southeastern US is a much larger source than estimated previously.
The maps and system, called Vulcan, show CO2 emissions at more than 100 times more detail than was previously available. Until now, data on CO2 emissions were reported, in the best cases, monthly at the level of an entire state. The Vulcan model examines CO2 emissions at local levels on an hourly basis.
Researchers say the maps also are more accurate than previous data because they are based on greenhouse gas emissions instead of estimates based on population in areas of the United States.
To create the Vulcan maps, the research team developed a method to extract the CO2 information by transforming data on local air pollution, such as carbon monoxide and nitrous oxide emissions, which are tracked by the Environmental Protection Agency, the US Department of Energy and other governmental agencies.
The increased detail and accuracy of Vulcan will help lawmakers create policies to reduce CO2 emissions while also increasing scientists’ understanding of the sources and fate of carbon dioxide, researchers say.
Before now the only thing policy-makers could do was take a big blunt tool and bang the US economy with it. Now we have more quantifiable information about what is happening in neighborhoods, on roads and in industrial areas, and track the CO2 by the hour. This offers policy-makers something akin to a scalpel instead.—Kevin Gurney, assistant professor of earth and atmospheric science at Purdue University and leader of the project
Gurney says the inventory system quantifies all of the CO2 that results from the burning of fossil fuels such as coal and gasoline. It also tracks the hourly outputs at the level of factories, power plants, roadways, neighborhoods and commercial districts.
A preliminary analysis of the Vulcan data suggests that previous maps of US fossil fuel emissions were inadequate for current scientific and policy-making needs, Gurney says.
When you compare the old inventories to Vulcan, the new data show atmospheric CO2 differences that are as large as five parts per million in some US regions in the late winter. The levels in the global atmosphere only rise one and a half part per million every year, so this is the equivalent of three years of global emissions in the atmosphere that isn’t where we thought it was. This will be important for policy-makers and is enormous from a scientific point of view. It’s shocking.—Kevin Gurney
Gurney says this change isn’t only due to people moving to the southeast, but also because of the approximations of previous estimates.
The three-year project, which was funded by NASA and the US Department of Energy under the North American Carbon Program, involved researchers from Purdue University, Colorado State University and Lawrence Berkeley National Laboratory.
To extract the CO2 information from the data on other pollutants, research scientists in the Office of Information Technology at Purdue developed a computational system to apply Gurney’s methods to existing information.
Once the data was converted to determine the CO2 emissions, it was combined with geographic information systems (GIS) data to layer the emissions onto roads and other infrastructure at the Earth’s surface. The current emissions are based on information from 2002, but the Vulcan system will soon expand to more recent years.
Vulcan is expected to complement NASA’s planned December 2008 launch of the Orbital Carbon Observatory satellite, which will measure the concentration of CO2 in the Earth’s atmosphere.
The Vulcan data is available to download from the Web site at http://www.eas.purdue.edu/carbon/vulcan. Smaller summary data sets that offer a slice of the data and are easier to download also are available for non-scientists on the Vulcan Web site. These can be broken down into emission categories, such as industrial, residential, transportation, power producers, by fuel type, and are available by state, county, or cells as small as six miles (10 kilometers) across.
A video of the maps and simulations of the atmospheric fate of fossil fuel CO2 also can be viewed on YouTube at http://www.youtube.com/watch?v=eJpj8UUMTaI.
The animation was created by Bedrich Benes, assistant professor of computer graphics technology and a research scientist in Purdue’s Envision Center for Data Perceptualization, and computer science graduate student Nathan Andrysco. The animation required a year to produce, and the rendering of the animation required nine hours to produce the 2,000 images that make up the 60-second video.