Smog Lays Its Gunky Shroud on the Valley

A blanket of some of the foulest air of the year covered the San Fernando Valley and most of the Southland Thursday and Friday, marring a mild smog season that still may shape up to be the best in decades.

Stagnant air flow, powerful sunshine and a persistent, strong inversion layer combined to shroud most of Southern California with the year’s worst concentrations of ozone--the potent, lung-scarring gas that makes Southern California’s air the unhealthiest in the nation.

The Valley suffered through another day of heavy smog, with more predicted for today. A Stage 1 alert, in which people are advised to curtail physical activity, is forecast for today.

In the Santa Clarita Valley, the AQMD declared a health advisory for the fourth consecutive day Friday, warning residents to refrain from activities such as running and swimming, said AQMD spokesman Bill Kelly. The agency has issued a health warning for the area again today. There were no health warnings issued for the Antelope Valley Friday, and none were predicted for today.

Despite the dirty brown air Friday, the number of days when air pollutants exceed federal air quality standards in the San Fernando Valley and adjoining areas has declined steadily over the past decade.

In Santa Clarita, for example, the number of smoggy days went from 104 between 1980 and 1982 to 66 between 1990 and 1992. In Reseda, smoggy days during the same period went from 87 between 1980 and 1982 to 40 between 1990 and 1992.

Despite the third consecutive day of temperatures over 100 degrees, 40 Valley schools opened the football season. A prep football game between Grant High School of Van Nuys and Tujunga’s Verdugo Hills High School was played Friday afternoon in Van Nuys, where the temperature was 100 degrees.

“We were out here yesterday when it was just as hot and smoggy to watch my son Dean play on the B team,” said Linda DeMoss of Tujunga, watching her daughter, Mendy, a Verdugo Hills cheerleader, for signs of fatigue.

“(But) it’s the first (few) games of the season, and I don’t think anything will stop them. Not the heat. Not the smog.”

First-stage smog alerts were called in the San Gabriel Valley, San Bernardino and Riverside on Friday. Most other inland areas of Los Angeles, Orange, San Bernardino and Riverside counties also suffered unhealthful air but barely skirted the hazard warnings.

“Thursday was the worst day we’ve experienced so far this year (in Southern California), and today (Friday) isn’t much better,” said Joseph Cassmassi, senior meteorologist for the South Coast Air Quality Management District. “It’s been a very, very persistent stagnant air mass sitting over us.”

For many people in the smoggiest areas, eyes teared, chests tightened and the slightest outdoor exertion caused breathing problems. Even seasoned meteorologists could think of no better word to describe Friday’s air than gunky . In addition to ozone, nitrogen dioxide--the whiskey-brown pollutant that obliterates skylines--was severe.

“It looked really bad out there yesterday, as it has today,” Cassmassi said Friday. “It’s air pollution, it’s Los Angeles and it’s summer--finally. This has been a phenomenally clean summer, and that’s directly a result of the weather.”

For much of the summer, an upper-level low-pressure layer has hovered over the Southwest, bringing good wind flow, cloud cover, cooler than usual upper-atmosphere temperatures and a weak inversion layer--conditions that are not friendly to smog.

The year’s two worst smog days came as the AQMD board held hearings on a controversial new strategy to combat industrial air pollution. On Thursday and Friday, the agency was debating whether to adopt a plan called RECLAIM, which allows Southland businesses to choose their own methods of smog control and trade pollution credits to reach a goal of slashing emissions 75%. The board will convene a final hearing on Oct. 15.

Ozone, a colorless gas that forms when hydrocarbons and nitrogen oxides bake under the sun, can permanently impair respiratory function and prematurely age lungs, pulmonologists say.

For longtime residents, the heavy smog was a reminder of the old days, when conditions were much worse. Less than a decade ago, bouts occurred much more frequently, often lasting most of the summer. In the 1970s, pollution often peaked at concentrations twice as bad as Friday’s.

This week’s worst air, as usual, was in Glendora, the nation’s smog capital, where ozone concentrations peaked Friday at .25 parts per million--more than twice the concentration that health officials deem safe to breathe.