Valley air stinks and will for years to come. It drives off business and sickens people to death. The American Lung Association, among others, annually reminds us how bad off we are. But those of us who've moved around the country can take that one step further.
How about tracking the air in places you've previously lived? OK, it's a snapshot in time -- you don't live there now, but bad air (water, crime, etc.) tend to be trendy, lingering for years.