Once again the ozone scaremongers have set their sites on NC. The Surface Transportation Policy Project, a Washington based environmental pressure group, has claimed that Charlotte, the Triad, and the Triangle have all had close to a 50 percent increase in high ozone days between 1993 and 2002. They compare two five-year periods: 1993-1997 and 1995-2002.
This study appears to have been carefully crafted to get the desired result. Apparently the group did not adjust for the change in the number of ozone monitors in these areas over the 10 year period, although when contacted they couldn’t tell us exactly what their methodology was. Over the last decade, the number of monitors in each of these areas has increased by about a third. The more monitors in an area the more likely it is that one of them will register high ozone. They also carefully chose which years they wanted to focus on.
Also if we look at the last six years instead of the last 10 we find a significant decrease in the number of ozone days. Looking at the difference between 1997-1999 and 2000-2002, and adjusting for changes in the number of monitors, Wake and Mecklenburg Counties have experienced a reduction of about 10 high ozone days per monitor per year, while the triad had a recution of about 2. The main point is that statistics can often be manipulated to show the desired result.
For an extensive discussion of ozone issues see my policy report
