Earlier this month (May '09), I visited Fresno, California. People ask "why did you go to Fresno? That's the armpit of California". I believe Bakersfield is, but I understood what they were saying. Fresno isn't actually that terrible, but the air quality is... intense.

I have never visited a place in April and not been so disgusted (relative to the month),with the poor air quality. I've been to Houston before, in August, and saw black skies surrounding us--we couldn't even roll down the window at a Wendy's to order our food without coughing. Sadly, that's pretty normal for Houston in August.

Yet, I digress, smog season is rolling around earlier and earlier every year and it's beginning to bug me. I decided to do some research, make some maps, and impress myself with California's notoriously awful air quality.

This year's first unhealthy (for sensitive groups) air day was April 23rd (I believe), and it was for Bakersfield, California. Why was it such a day for this city of 300,000+ people? 86% of the oil drilling in the state takes place in Kern County, Diesel trucks along I-5 going to and from Los Angeles aren't helping, the intensive agriculture is notorious for it's pollutants, and last but not least, the geography--since it's surrounded on three sides by mountainous terrain that holds in the pollutants until 6-8pm. The lack of wind in the San Joaquin valey doesn't help either. Little if any smog from the Los Angeles / Inland empire arrive in the lower San Joaquin valley, since the pervailing winds (from West to East), and the fact that most wind that arrives in California comes from the Northwest direction (review how High Pressure systems work, since there always seems to be one off of California's coast).

Other areas in California that experience dreadful pollution is San Bernardino & Riverside counties (especially Metro and western), since they recieve most of the particulate matter from Los Angeles and themselves. The Fresno-Visalia area is nearly as bad as the Inland empire (and when combined with Bakersfield, is actually worse). The Sacramento-Elk Grove-Roseville area also experiences a very high amount of unhealthy air quality days, as does the Pleasonton-Stockton area.

Del Norte and Trinity countries were found to have the best air quality in the state, by far.

At 85 Particulates per million (PPM), lung damage begins to occur with every breathe, yet the AQI index has unhealthy (for sensitive groups) rating start at 100+ PPM, which I find to be arbitrary. Thus, I feel this rating should start at 85 PPM, and my 'day-to-day' map reflects that. When particulate matter gets above 85 PPM, imagine that a smoker is constantly around you at that point--that's the damage your lungs are recieving. Air quality is worst from 3-6pm, and begins to fall at 7-8pm. This has to do with temperature inversion (traps the bad air close to the ground) and atmospheric conditions, and these conditions are usually more dramatic in vallies.

1 in 6 children have asthma in Fresno, 3x higher than the national average. 12-16 non-smokers die every day in California due to complications from living in an area bad air quality too long.

I use the term "Particulate Matter" to be synonymus with soot, aerosols, PM ~2.5 (2.5 micrometers in size), PM ~10 (10 micrometers in size), soot, haze, pollutants, diesel, dust, small debris--all that is often present in California air, especially on bad air days.