China's nitrogen dioxide concentration varies according to season,

While nitrogen dioxide vertical column concentrations above central and eastern Europe and parts of the East Coast of the United States have been either static or exhibiting a small decrease, there is a clear and significant increase over China,

I really don't know how many passes will be thrown my way this season. It varies from year to year but all I can do is my best and don't worry about things out of my control.

He started the season off a little slow. But he's getting in better position as of late.

It really, really varies geographically.

On the face of it, installing new plant to reduce sulphur dioxide emissions is a good thing.