December 1, 2008 Biogeochemists located where the most carbon dioxide emissions occur in the U.S. using a new mapping system. With this program-available to anyone on the Web-researchers were able to extract information about carbon dioxide emissions by transforming data on local air pollution and combining it with geographic information systems (GIS) data to layer the emissions onto infrastructures at the Earth's surface. The map helps us learn more about carbon emissions and gives scientists a way to check the accuracy of satellite images.
The Environmental Protection Agency estimates emissions in the United States rose almost 15 percent between 1990 and 2006, and the number will continue to rise. Carbon dioxide is mainly responsible for the increase. A new high-tech map reveals the areas in the country most responsible for the carbon dioxide problem.
Carbon dioxide (CO2) is the most abundant greenhouse gas in our atmosphere. Its sources can be found almost everywhere -- from cars, to cows, to power plants -- but scientists are still trying to figure out which parts of the country are pumping out the most CO2.
In the past, CO2 levels have been calculated based on population, putting the Northeast at the top of the list. Now, a new map called Vulcan reveals for the first time where the top carbon dioxide producers are in the country. The answer surprised Kevin Gurney, Ph.D., a biogeochemist at Purdue University in West Lafayette, Ind.
"There are a lot more emissions in the Southeast than we previously thought, and a lot of that is because it's not necessarily associated with where people live directly, but actually where industry and activities are," said Dr. Gurney.
The high-resolution map shows 100 times more detail than ever before and zooms in to show greenhouse gas sources right down to factories, power plants and even roadways. An animated version of Vulcan reveals huge amounts of greenhouse gas gets blown toward the North Atlantic region.
"We've never had a map with this much detail and accuracy that everyone can view online," Dr. Gurney said.
The map helps scientists better visualize and target the areas where CO2 emissions are the highest and help those areas reduce their negative impact on Earth. It can be downloaded for free online from the Purdue University Vulcan Project Web site.
ABOUT CARBON DIOXIDE: The concentration of carbon dioxide in the atmosphere has increased by about 30 percent since the beginning of the industrial revolution in the late 1800's. Most of this increase comes from using fossil fuel -- coal, oil and natural gas -- for energy, but approximately 25 percent of the carbon came from changes in land use, such as the clearing of forests and the cultivation of soils for food production. Natural sources of atmospheric carbon include gases emitted by volcanoes, and respiration of living things. We breathe in oxygen, and breathe out carbon dioxide.
ABOUT AIR POLLUTION: Air pollution is made up of many kinds of gases, droplets and particles that can remain suspended in the air. This makes the air dirty. The easiest way to visualize airborne particles (also called aerosols) is to exhale outside on a cold day and watch the fog come out of your mouth as water vapor forms into water droplets. The same thing happens in the atmosphere, but for different reasons. Under certain conditions individual molecules come together and form particles -- a chemical soup. In the city, air pollution may be caused by cars, buses and airplanes, as well as industry and construction. Ground-level ozone is created when engine and fuel gases already released into the air interact when sunlight hits them. Ozone levels increase in cities when the air is still, the sun is bright and the temperature is warm.
The American Geophysical Union and the American Meteorological Society contributed to the information contained in the TV portion of this report. This report has also been produced thanks to a generous grant from the Camille and Henry Dreyfus Foundation, Inc.