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Almost 30 percent of carbon pollution in the United States comes from transportation, mostly from cars and trucks.

"It’s really a difficult issue for the states to tackle individually because obviously vehicles move from state to state," Vicki Arroyo says. Arroyo directs the Georgetown Climate Center, which helps coordinate an alliance of mid-Atlantic and northeastern states working together to address this challenge.

This year, 10 members of the alliance are designing a pricing plan to reduce the emissions from transportation. The idea is to charge fuel suppliers for the pollution they generate. The revenue would be used to help build a low-carbon transportation system.

Arroyo says the goal is to find regional solutions that help reduce the emissions from climate change by supporting development of electric vehicle charging infrastructure and, providing incentives for people to move to electric vehicles or to use transit.

"It could also generate resources for spending on making our transportation system more resilient to the impacts of climate change," she says.

Arroyo says regional collaboration could help solve a problem that stretches beyond the borders of any single state.

Reporting credit: Sarah Kennedy/ChavoBart Digital Media.