How Trump's decision to roll back the Clean Power Plan could affect the environment

The Clean Power Plan hasn't gone into effect yet.

So what could that mean for the environment?

The biggest criticism of undoing the plan is that continuing emissions at current levels would not slow down rising global temperatures, which could lead to further consequences that hurt the environment and public health.

In 2015, carbon dioxide emissions from energy were 12 percent lower than levels in 2005, according to the U.S. Energy Information Administration.

President Barack Obama said the additional reductions would be "like cutting every ounce of emission due to electricity from 108 million American homes. Or it's the equivalent of taking 166 million cars off the road," in his speech announcing the plan in 2015.

The Clean Power Plan hasn't gone into effect yet, so there is no data to show if it had an impact on emissions.

Carbon dioxide and other gases stick around in the atmosphere after they are released from burning fossil fuels. Those gases trap heat, which in turn makes temperatures around the world go up, a phenomenon called the "greenhouse effect."

President Trump criticized that difference as "tiny" when he announced that the U.S. would leave the Paris Climate Agreement.