Smog Figures Are a Breath of Fresh Air
From the foothills of San Bernardino County to the coast of Orange County and the valleys of Los Angeles, Southern Californians breathed the cleanest air on record in the 1990 smog season that officially ended Wednesday, records show.
Officials said regulations lowering emissions from cars and industry deserve much of the credit for the dramatic improvement in air quality, but favorable weather also contributed.
“This is mind-boggling,” said Joseph Cassmassi, senior meteorologist with the South Coast Air Quality Management District who has analyzed smog data for nine years. “When you compare it with the past, it’s like night and day. There’s really been a dramatic improvement.”
Days of smog alerts in the basin--which includes Los Angeles, Orange, San Bernardino and Riverside counties--declined by 24% this smog season compared to 1989, which also was considered a light year.
The season, which runs from May through October, is believed to be the best in more than 40 years of record-keeping in Southern California. Although air quality has been improving for years, no decline has been this large. When weather is factored out, the average decrease in recent years has been four less alert days a year, Cassmassi said.
Despite the improvements, the basin remains the smog capitol of the nation with air quality that is three times worse than any other area. On an average of every four or five days since May, residents in at least one city within the region breathed concentrations of pollution that officials consider unhealthful.
Also, visibility has not necessarily improved. Much of the haziness comes from a mix of moisture and soot. “We can get ozone to zero and the public might not even notice it because they gauge air quality by visibility,” AQMD Chairman Norton Younglove said.
From May through October, alerts for ozone, the prevalent pollutant in the region, were called in at least one city on 41 days, AQMD data shows.
That compares to 54 days in 1989 and 77 in 1988. Back in 1977, they occurred nearly three times more frequently, with 121 days. The alerts are triggered when pollutants reach concentrations so high that health warnings must be issued under law.
In Orange County, La Habra was the only area that experienced alerts out of five stations in the county where pollutants are measured. Four alerts were recorded there--twice as many as in downtown Los Angeles--while Los Alamitos, Anaheim, Costa Mesa and El Toro had none.
The nation’s smoggiest city--Glendora, nestled at the foot of the San Gabriel Mountains--had a much lighter season, with 28 days compared to 37 last year and 71 in 1986.
“We’re encouraged, but it’s still flat-out awful,” said Tim Little, executive director of the Coalition for Clean Air, a Santa Monica-based environmental group. “It doesn’t show enough of a decline to even put us in the same league with the rest of the country.”
Ozone, created when a mix of pollutants from cars, businesses and consumer products bake under the sun, is a powerful irritant of the lungs. It is especially harmful to children, people with respiratory disorders, the elderly and people who exercise outdoors. There also is increasing evidence from national researchers that the pollutant causes premature aging and permanent damage that could trigger chronic lung disease in healthy people.
Dr. Robert Phalen, director of the Air Pollution Health Effects Laboratory at UC Irvine, said the air-quality improvements recorded this year are significant enough to benefit the health of everyone living in the basin.
“People with lung disorders would notice that this was an easier year for them,” Phalen said. “And those of us who don’t have a lung disorder are benefiting even though we don’t notice it because smog episodes slowly erode lungs.”
Dr. Ray Casciari, a physician in Orange and past president of the county’s branch of the American Lung Assn., said he has seen no improvement in the health of the estimated 2,000 lung patients his office treats a year. But he said they have severe ailments, and “all they need is one sudden bad exposure” to smog to need medical care.
“They can cross the street or drive on the freeway and be exposed enough to set off an attack,” Casciari said. “Even though the average smog situation is better, it will take years of work to reach the point where it’s not affecting people, especially sick people.”
The AQMD has vowed to eliminate smog alerts by the year 2000 and comply with all federal health standards by 2007 with its 20-year plan.
A Stage 1 alert is called when ozone reaches .20 parts per million. A Stage 2 is above .35 p.p.m. The air is considered unhealthful when it exceeds the federal standard of .12 p.p.m.
This year showed a 60% decline in the number of hours that the region exceeded the Stage 1 level, Cassmassi said. That means not only is the problem shrinking in size, but also duration. Smog bouts are lasting shorter periods of time, the data shows.
Ozone peaks from May through October because of strong sunshine and stagnant air, which traps pollutants close to the ground. Most of the pollution builds up from cars and industry in Los Angeles and Orange counties, then moves inland and east toward the mountains.
One of the trends that delighted officials most was the improved air in Riverside and San Bernardino counties, especially in Norco, Upland and San Bernardino. Those areas typically have been the recipient of poor air blown in from Los Angeles and Orange counties.
Also, this was the first season that many cities, including Anaheim, El Toro, Whittier, Norco and Reseda, have not experienced at least one alert.
“The basin’s main metropolitan area is essentially episode-free,” Cassmassi said. “We’ll have an odd episode in Anaheim or El Toro, but I believe we won’t see anything in the double digits again in the coastal and near coastal areas.”
Cassmassi said three-quarters of the recorded improvement in air quality should be attributed to reductions in emissions. He said there were no unusual weather patterns this year, so weather accounts for only a quarter of the reduction.
State air-quality officials have analyzed only the first half of the smog season, but they suspect that weather is the main reason for dramatic year-to-year declines.
SMOG SEASON
The 1990 smog season, which started May 1 and ended Wednesday, was the cleanest on record in the Los Angeles Basin, which includes Orange, Los Angeles, San Bernardino and Riverside counties. Air is measured daily in 37 cities. This chart reports smog alert days in five Orange County locations and a selection o other cities. Officials say recent rules forcing cutbacks in industry and autos emissions get most of the credit for the 24% basinwide improvement over 1989.
Smog Alert Days 1990 1989 1988 1987 1986 1985 1984 Glendora 28 37 54 51 70 68 67 Pasadena 7 17 18 15 33 41 49 San Bernardino 7 22 31 27 41 30 36 Riverside 15 18 16 20 19 35 29 Norco 0 3 7 9 12 20 19 La Habra 4 5 2 6 8 13 14 Downtown L.A. 2 1 2 2 8 9 8 Reseda 0 5 4 2 5 9 6 West L.A. 0 1 2 1 1 4 5 Anaheim 0 4 1 3 1 11 5 El Toro 0 2 2 0 1 7 3 Costa Mesa 0 0 0 0 0 1 1 Long Beach 0 0 0 0 0 1 1 Los Alamitos 0 0 1 0 0 0 0 Total in basin*: 41 54 77 66 79 83 97
*The basin total is the number of days when at least one monitoring station within the four counties reached the smog-alert limit for ozone, which is .20 parts per million.
Source: South Coast Air Quality Management District
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