In search of cleaner air – Part 2: The South Coast Air Basin

On Jun. 13, 2014 I wrote: “In search of cleaner air – Part 1: The San Joaquin Valley.” Part 1 covers air quality progress in California’s eight-county San Joaquin Valley (Valley). In this, the second part, meanwhile, the focus is on southern California and the South Coast Air Basin specifically.

South Coast: An air pollution hot spot[1]There is no question other states such as Illinois, Pennsylvania, Texas and Utah, to name but four, also have pollution problems of their own. Yet, why all of the attention paid to California? One reason and perhaps the main one is because California is one of America’s worst air offender states; a second reason has to do with the fact that I was able to locate pertinent pollutant data for the South Coast Air Basin relatively quickly; the third reason being that if California is successful in making marked improvements in the quality of the air in major metropolitan centers such as Los Angeles as well as in regions like the Valley, then this should have implications for other regions that are as well grappling with dirty air. So, focusing on the Golden State makes sense.

As in Part 1, considered here also are the three sources of:

  1. Stationary
  2. Areawide
  3. Mobile

Sectors within the Stationary category include: Fuel combustion, waste disposal, cleaning and surface coatings, petroleum production and marketing, and industrial processes.

Sectors within the Areawide category include: Solvent evaporation, and miscellaneous processes.

Sectors within the Mobile category include: On-road motor vehicles, and other mobile sources.

Meanwhile, the identified emissions of concern are these: Total organic gases (TOG), reactive organic gases (ROG), carbon monoxide (CO), nitrogen oxides (NOx), sulfur oxides (SOx), particulate matter (PM), coarse particulates (PM 10) and fine particulates (PM 2.5).

So, this is the way the South Coast’s numbers for 2012 in tons per day check out:

  • TOG – 1317.8
  • ROG – 466.4
  • CO – 2271.8
  • NOx – 512.0
  • SOx – 17.6
  • PM – 216.8
  • PM 10 – 153.6
  • PM 2.5 – 68.4

(Source: “Almanac Emission Projection Data (Published in 2013), 2012 Estimated Annual Average Emissions, South Coast Air Basin,” California Environmental Protection Agency Air Resources Board. See:

Holding true for the air basin in the South Coast as is the case for the Valley is that in the mobile sources category CO and NOx concentrations are the highest. Different for the South Coast in this regard is ROG where the highest concentrations are mobile-source related.

Mobile sources (in tons per day):

  • ROG – 239.8
  • CO – 2114.4
  • NOx – 512.0

Likewise, SOx is highest in the stationary sources category in this case weighing in at 10.1 tons per day. Meanwhile, and unlike with respect to the Valley where the highest concentration of TOG was in the areawide category, TOG has its highest concentration in the stationary sources category coming in at 866.8 tons per day.

Rounding out the list are PM, PM 10 and PM 2.5 which all have their highest concentrations in the Areawide category, these in tons per day being:

  • PM – 177.1
  • PM 10 – 96.1
  • PM 2.5 – 32.4

Finally, in a year-to-year comparison, 2012 versus 2010, all emissions totals for the South Coast Air Basin were less in 2012. For 2010 the totals in tons per day are:

  • TOG – 1390.8
  • ROG – 543.7
  • CO – 2599.8
  • NOx – 603.2
  • SOx – 19.3
  • PM – 224.2
  • PM 10 – 160.0
  • PM 2.5 – 71.4

(Source: “Almanac Emission Projection Data (Published in 2013), 2010 Estimated Annual Average Emissions, South Coast Air Basin,” California Environmental Protection Agency Air Resources Board. See:

I realize this is a lot of information to process, the bottom line, of course, being that even in the South Coast Air Basin, there is progress and the air there has gotten cleaner – that is, with respect to the named emissions, mind you – regardless of whether the improvement in this sense was only slight or not. All things considered, the good news is that air quality in the South Coast region is heading in the right direction. An encouraging sign to be sure!

Image above: NASA

– Alan Kandel