Bend, OR -

If you look over a new map showing average annual household carbon footprint by ZIP code, there's a surprise in what sticks out in Central Oregon.

Powell Butte, 97753, is the only ZIP code in this part of the state where researchers calculated households are responsible for more than 50 metric tons of carbon dioxide each year. The reason: the number of cars and trucks per household and the number of miles they go each year.

"What we count is all the miles they travel in a year," said Chris Jones, lead coordinating researcher at the CoolClimate Network at the University of California, Berkeley.

The data used by the network, a division of Berkeley's Renewable and Appropriate Energy Laboratory, showed households in the Powell Butte ZIP code average 2.5 cars and trucks and drive them an average of 42,624 miles per year. In contrast the households in the 97702 ZIP code, which covers a portion of Bend, average 1.9 cars and trucks and drive them an average of 26,724 miles per year.

The average household in 97702 is responsible for 48 metric tons of carbon dioxide per year. Carbon dioxide is a greenhouse gas that contributes to climate change.

The network compiled national household energy, transportation and consumer spending surveys, along with local census, weather and other data -- 37 variables in all -- to determine about how much greenhouse gas emissions households are responsible for around the country. It divided the data by ZIP code. Jones said the affluence of an area may also cause an increase in the carbon footprint. As people have more money they buy more things, making for a bigger footprint.

Having looked over the map and read scientific articles about the research, Colin McConnaha, climate change specialist with the Oregon Department of Environmental Quality, said the transportation figure makes a big difference in the carbon footprint for the different ZIP codes. As a result suburban ZIP codes on the map show a larger carbon footprint, more carbon dioxide, put off annually by households.

"Because those are the ZIP codes that people drive the most," McConnaha said.

While not suburban, the people living in Powell Butte, an unincorporated community in Crook County, do drive often.

The Powell Butte ZIP code has 2,016 people living in it, according to the U.S. Census Bureau. If they work, they likely drive to Bend, Redmond or Prineville to do so.

"Most of them are farmers though," said Robin Story, shift leader at the Powell Butte Country Store.

The little convenience store also sells gas, she said. When folks in Powell Butte want to do more shopping they drive to the population hubs around Central Oregon.

In contrast there are 40,483 people in the 97702 ZIP code, which covers the southern section of Bend.

If people want to lessen their carbon footprint, Jones, the Berkeley researcher, said people can start by switching to a more fuel-efficient car or truck. They can also "chain" their trips by lining up errands so they're done together, and carpool.

"Just trying to reduce the amount of miles you drive by planning your trips a little better," Jones said.

State Rep. Mike McLane, R-Powell Butte, said he hadn't seen the map, and hearing about it didn't cause him alarm or concern about his district. He said his biggest concern at the moment is the unemployment issue in Crook County.

"My focus is not how many diesel pickups reside in Powell Butte, but whether my neighbors in Powell Butte and Crook County have jobs in order to ensure their kids go to school and their needs are met," McLane said.