2016 South Coast Air Basin air pollution half-year report

On June 22nd, afternoon high temperature for Fresno hit 102 – same as the day before.

Making my way back from a visit to the financial institution where I do my banking, I drove past a clinic that specializes in treating allergy and sinus conditions, and on the electronic display sign out in front of the clinic, illuminated in red, was the word “unhealthy,” referring, of course, to the quality of the San Joaquin Valley’s air, more than likely. Everyone passing this same sign displaying the message it did and upon its observation, should be thinking the same thought – so sad the air is so bad!

All of which makes me wonder: While the Valley is baking under a summer sun, its inhabitants immersed in a toxic-air soup, how are those located south of the Tejon Range – separating the sprawling San Joaquin Valley from the equally if not more sprawling South Coast Air Basin – faring, and if they are faring any differently or better.

A quick look at the “Latest Ozone Summary for Selected Regions (Preliminary Data in PST)” table for yesterday shows 8-hour numbers that were worse in the South Coast Air Basin than what was recorded in the San Joaquin Valley – 93 parts per billion of air versus 86 ppb, respectively.


For the seven-day period ending June 22nd, the South Coast Air Basin for ozone measured over 8 hours, registered 109 ppb compared to the Valley’s 94 ppb.

And, in the year-to-date category (column), the difference is more pronounced – 114 ppb (South Coast Air Basin) against the Valley’s 94 ppb, a difference of 20 ppb.

Meanwhile, for the National Ambient Air Quality Standard for 8-hour ozone of 75 ppb at the Highest Site, under the “National” designation on the “Latest Year’s (Annual) Ozone Summary for Selected Regions (PST)” table, the state’s south land recorded 81 exceedance days for year 2015 versus the San Joaquin Valley’s 82, while so far this year (2016), the South Coast’s 30 exceedance days is worse than the Valley’s 19.

That’s ozone. Regarding fine particulate matter (PM 2.5) pollution:

In the South Coast, only 9 exceedances (at Highest Site) this year so far (National Ambient Air Quality Standard for PM2.5 of 35 micrograms per cubic meter of air) while between Nov. 1, 2015 and Feb. 28, 2016 at Highest Site, a total of 2 exceedance days only.

On the other hand, between Nov. 1, 2014 and Feb. 28, 2015 for PM 2.5 measured over 24 hours, exceedance days numbered 35. Quite a disparity from one year to the next. A presumptive change in climatic conditions 2015-’16 compared to 2014-’15, might account for the difference. 2015-’16 was a strong El Nino year.

For comparable data regarding the San Joaquin Valley, see: “2016 San Joaquin Valley air pollution half-year report” here.

Image above: NASA

2 thoughts on “2016 South Coast Air Basin air pollution half-year report”

  1. IT seems like the great progress in reducing those numbers through the 80s and 90s and early 2000 has ground to a halt and most of the low hanging fruit have been gotten. What are the valley’s long the plans and what are the remaining major contributors?

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