Ozone smog represents the single most challenging pollution problem the country is facing.

The report doesn't give a realistic picture of the state of air pollution in the country. It is mainly about fomenting fear, because fear is what keeps the donations flowing.

The AP's analysis of health risks posed by industrial pollution across the country is a substantial contribution to the public's understanding of where greater attention needs to be focused.

Fortunately, reducing light pollution is easy. Plus, it's good for national parks and good for America generally.

In ways we've looked at pollution in the past, coal has cleaned up. But the bigger problem we face now is carbon dioxide, which clean coal plants still emit.

Each country has already begun to identify a portfolio of actions to improve their energy security, reduce pollution and cut their greenhouse gases. What we are going to do with the partnership is find some alignment of those strategies so we can expand and promote investment in technologies that will help meet those goals.