NEW YORK (Reuters) - Counties in the main U.S. petrochemical and driving hubs top the country's output of the planet-warming gas carbon dioxide, emitting about three times more CO2 than the top county in New York does, researchers said on Thursday.
Harris County in Texas emitted more than 18.6 million tons of CO2 in 2002, the latest year for which data was available, according to Vulcan, a three-year project funded by NASA and the U.S. Department of Energy. The county is home to oil and natural gas plants and Houston, which has about 2 million people.
Los Angeles County, home to car-clogged highways and about 4 million people, emitted nearly 18.6 million tons, said researchers from Purdue University, Colorado State University and Lawrence Berkeley National Laboratory, who led the project.
Suffolk County, in the metropolitan area of New York and home to nearly 1.5 million, emitted about 6 million tons and ranked 19th.
Vulcan developers hope the data will be used by governments as a baseline to track progress of U.S. cities and states in reducing the pollution that most scientists say could lead to deadly storms, floods and droughts.
The Environmental Protection Agency also measures greenhouse data, but its inventories are so far more centered on emissions sources rather than regions.
"Vulcan is going to show how places are doing in climate plans," Kevin Gurney, a Purdue professor who led the project, said by telephone.
The Vulcan data, which researchers said would soon be updated, came during early days of the U.S. fight against climate change.
About 28 U.S. states have set greenhouse emissions limits or are expected to do soon do so soon, while the U.S. Congress is mulling several bills that would regulate greenhouse gases nationwide. President George W. Bush this week outlined a plan to halt the growth of emissions by 2025.
Gurney cautioned against using Vulcan to blame who is most responsible for emissions. San Juan County in New Mexico, for instance, was listed as the sixth largest U.S. emitter. But most of its emissions come from coal-fired power plants that send power to fast growing cities in Arizona and Nevada.
"When you get down to nuts and bolts, you realize everyone is in this together," he said.
Here is Vulcan's list of top U.S. polluters by county in million tons of CO2 per year:
1. Harris, Texas (Houston), 18.625
2. Los Angeles, Calif. (Los Angeles), 18.595
3. Cook, Ill. (Chicago), 13.209
4. Cuyahoga, Ohio (Cleveland), 11.144
5. Wayne, Mich. (Detroit), 8.270
6. San Juan, N.M. (Farmington), 8.245
7. Santa Clara, Calif. (San Jose), 7.995
8. Jefferson, Ala. (Birmingham), 7.951
9. Wilcox, Ala. (Camden), 7.615
10. East Baton Rouge, La. (Baton Rouge), 7.322
11. Titus, Texas (Mt. Pleasant), 7.244
12. Carbon, Pa. (Jim Thorpe), 6.534
13. Porter, Ind. (Valparaiso), 6.331
14. Jefferson, Ohio (Steubenville), 6.278
15. Indiana, Pa. (Indiana), 6.224
16. Middlesex, Mass. (Boston metro area), 6.198
17. Bexar, Texas (San Antonio), 6.141
18. Hillsborough, Fla. (Tampa), 6.037
19. Suffolk, N.Y. (New York metro area), 6.030
20. Clark, Nev. (Las Vegas) 5.955
Editing by Walter Bagley