Critics play a dangerous game when they denounce the science and law EPA has used to defend clean air for more than 40 years. The American people know better.

Greenhouse gas pollution, through its contribution to global climate change, presents a significant threat to Americans health and to the environment upon which our economy and security depends.

I love disagreements. I love the democratic process. If I'm in a room where everybody agrees, I start to nod off.

Transparency is all about letting in and embracing new ideas, new technology and new approaches. No individual, entity or agency, no matter how smart, how old, or how experienced, can afford to stop learning.

Climate change is the greatest threat of our time.

There is no threshold level of fine particle pollution below which health risk reductions are not achieved by reduced exposure.

Critics play a dangerous game when they denounce the science and law EPA has used to defend clean air for more than 40 years. The American people know better.