- TNMHC is total non-methane hydrocarbons, AIRS parameter code 43102.
- Targeted compounds are the 55 volatile organic compunds individually measured at PAMS stations.
- Time is daylight saving time.
- ppbC is parts per billion carbon.
- Morning hours (6-9 a.m.) are used because the daily ozone reaction cycle has not begun to convert the VOCs to ozone.
|Source: Mark Schmidt of EPA prepared this chart based on data in the AIRS system.|