Why is this important?
Ozone in the upper atmosphere is necessary for our survival. However, ozone at the ground level is harmful to health. Chemicals from car exhaust and some industries can react with sunlight to produce ground level ozone, also known as smog. Severe smog can cause acute symptoms, such as shortness of breath and throat irritation. Even at the lower levels, smog aggravates asthma and breathing problems, oxidizes building surfaces, and slows plant growth.
What is the measure?
The chart summarizes progress made toward meeting state and federal ambient air quality standards. Typically, these data monitor concentrations of pollutants measured over time (e.g. ozone—measured in parts per million averaged over one hour).
How are we doing?
Other than in 2004, a few days each year we failed to meet the state 1-hour ozone ambient air quality standards and the federal 8-hour ozone ambient air quality standards. Regulations require that all air districts attain these standards at the earliest practical date. Final allowable date is not specified for the 1 hour attainment; it is 2009 for the 8-hour attainment.
We produce a portion of the emissions affecting the county’s air quality. However, pollutants from the central valley are a critical factor in the county’s failure to meet standards, and one over which we have no direct control.
Another challenge is to balance air quality goals with the need to reduce the risk of destructive wildfires through prescribed burning. Short-term exposure to smoke from prescribed burns is one of the trade-offs for reducing flammable forest fuels that could otherwise create extremely high levels of pollution during extreme summer wildfires.