Climate change threatens the health of this planet and the well-being of its inhabitants through its direct effects on the environment. Change in global climate is ongoing and cumulative; unless people act soon to halt its progression, the damage it inflicts will be irreversible.

Carbon dioxide pollution is a major contributor to climate change. Power plants constitute the greatest single source of CO2 emissions in the U.S. — nearly 40 percent of the nation’s annual total. Currently, no CO2 emission limits exist for power plants, which is nearsighted and irresponsible.

The Environmental Protection Agency has proposed first-ever federal limits on carbon pollution from new fossil fuel-fired power plants. The performance standards this agency has proposed for emissions are achievable with the use of existing technology. Enactment and enforcement of these standards would reduce greenhouse gas emissions and climate change measurably, making the air cleaner and healthier to breathe.

That is good news for Maine, which is downwind of dozens of fossil fuel-fired power plants in the Midwest that pollute our air and likely contribute, directly or indirectly, to the state’s high incidence of asthma and other respiratory ailments.

Also, the EPA will announce soon a CO2 emission standard for the nation’s existing fossil fuel-fired power plants, which will have an even greater impact on cleaning up the air and combating climate change.

Maine’s congressional delegation should support the EPA’s new source performance standard to regulate CO2 emissions from new power plants.

Ron Barry, Lewiston