Two cities known for their red brick architecture and white snowy winters have been recognized as among the greenest in America, according to a recent study by Popular Science.

Boston and Cambridge were placed third and sixth, respectively, in the list of the “50 Greenest Cities in America,” which was based on data from the U.S. Census Bureau and the National Geographic Society’s Green Guide.

Electricity production from renewable sources, public transportation and carpooling, buildings certified by the U.S. Green Building Council and areas of public green space, and the city’s recycling program were considered in the study.

Portland, Ore. and San Francisco, Calif. topped the list.

Boston, which scored a 22.7 on Popular Science’s 30-point scale, was commended for its proposed plan to build a plant that will turn leaves and grass into electricity.

Former Environmental Action Committee Chair Spring Greeney ’09 said that although it is important for cities like Boston and Cambridge to continue their efforts to become more environmentally friendly, improvements in these historically progressive cities will not necessarily translate into advancements in less progressive cities in the south and Midwest.

Of the cities in Popular Science’s top 10, all but Chicago and Austin, Texas were in the coastal Northeast or Northwest.

Besides political attitudes and geography, education could also play a role in better environmental practices, according to Earth and Planetary Sciences Professor Daniel P. Schrag.

“I think cities like Cambridge and Boston with a lot of universities, students, that are more educated, are above average,” said Schrag. “Hopefully, this will spread.”

He added that Harvard can help lead a national initiative to lower emissions averages.

Schrag said he would like to see Harvard adopt a new plan for reducing energy usage.

Each department could be taxed for its energy usage and then given a credit based on its overall operating budget.

“In most buildings today, you ask, ‘Are we paying for heat in the middle of the night?’” he said. “The answer is ‘yes.’”

The University announced this fall a commitment to keep greenhouse gas emissions in its new science complex in Allston at 50 percent below the national standard.

Other projects to be completed within the next 20 years will remain below 30 percent of national standards.

—Staff writer Gabriel J. Daly can be reached at gdaly@fas.harvard.edu.