Southland On Course to Reclaim U.S. Smog Title

What the smog gods give they take away, and this year it appears they will take away the air pollution crown from Houston and return it to Los Angeles.

As the summer ozone season peters out, it leaves behind more polluted days in the four-county Los Angeles region this year than in the eight-county Houston area.

That means that the distinction of being the nation’s smoggiest metropolitan region, which Houston usurped two years ago, falls again to Los Angeles, although most of the smoggy air in this area occurs in San Bernardino and Riverside counties.

“We don’t wish high pollution levels on anybody. It’s hard to get excited about that,” said Barry Wallerstein, executive officer of the South Coast Air Quality Management District, which regulates emissions in the L.A. region. “But we have four times the population Houston has and a lot more cars, so the task at hand is more difficult.”

Officials in both states say the vagaries of weather account for differences in this year’s smog levels. And environmentalists say power plant emissions during California’s energy crisis may have contributed to Southland smog, although air quality officials dispute that.

For the last three years, the nation’s second and fourth largest cities have been jockeying, neck and neck, in a smog derby with political and human health implications. Democrats have accused President Bush of abetting lax regulations that led to dirty air in Texas, and health experts warn that excessive ozone, soot and dust cause respiratory illness, cancer and premature death.

L.A. smog is mainly a product of tailpipe exhaust; Houston is affected more by petrochemical plants and shipping. For years, it had been a one-horse race, until smog levels began plummeting across the Los Angeles Basin during the 1990s in response to stringent controls, while Houston experienced only slight progress.

As of Monday, 35 days with unhealthful levels of ozone, a colorless gas, had been recorded somewhere in the Los Angeles region. A few more may occur before the official conclusion of smog season come Halloween. Last year, there were 40 such days, according to the AQMD.

As usual, the filthiest air was in the Riverside-San Bernardino area, where onshore winds trap pollutants against tall mountains. Crestline remains the hot spot with 27 days of ozone above the federal limit of 120 parts per billion over a one-hour period.

Air quality officials say the progress this year is consistent with a long-term trend. The number of days of unhealthy ozone levels has declined about 70% across the Southland in the last decade.

In Texas, the progress has been more modest. Indeed, the chief reason the contest between the two cities is close is because California smog-fighters have acted more aggressively than their counterparts in Houston. Ozone levels in Houston are only slightly lower than a decade ago.

Nevertheless, as of Monday, Houston had recorded 26 days of unhealthful ozone levels--its best air quality in five years, according to the Texas Natural Resource Conservation Commission. At that pace, the metropolis is nearly certain to mark significant improvement over last year, when 44 such days occurred.

Bryan Lambeth, senior meteorologist for the commission, said a steady dose of wet weather in southeast Texas played a key role in snuffing out smog. But Houston, home to about 5 million people, is not in the clear yet; the smog season there lasts well into November, and more smoggy days are in the forecast, although probably not enough to overtake Los Angeles.

“Odds are good we’ll have at least five or six more days. The season is not over yet for Houston,” Lambeth said.

‘Split Decision’ for the 2 Cities

Houston also scored a higher concentration of ozone than did the Los Angeles area. The peak reading in the Texas community of Bayland Park was 194 parts per billion, a whisker shy of the level that triggers health alerts for the entire population. That edged out Glendora, a Los Angeles-area smog leader this year, which posted a peak reading of 191 parts per billion.

“That makes it a split decision,” Wallerstein said. “We had more unhealthful days, but Houston had a higher peak.”

Working against air quality in Southern California this year was a stubborn inversion pattern, in which a layer of warm air traps smog in inland valleys during summer like a Tupperware lid. This year, the inversion was lower and warmer than normal, preventing pollutants from escaping, explained Joe Cassmassi, senior meteorologist for the AQMD.

“There’s an outside chance that [Houston] might catch up, but to be honest, I doubt that will be the case,” he said. “Even if we [in L.A.] redeem the smog title, we’re cleaner than last year and that will continue the long-term trend.”

But environmentalists question whether the California energy crisis may have added enough extra pollution to restore Los Angeles’ title as the smog capital. Power plants worked overtime for much of the last year, including many old “peaker” plants that produce far more pollution than new facilities.

“I’m skeptical,” said Tim Carmichael, director of the Coalition for Clean Air. “I think there was an impact at the local level from running the dirty power plants that had been largely idle in the past.”

Indeed, power plant emissions during the first half of the year increased by 500 tons over the same period last year in the Los Angeles region, according to the AQMD. It appears, however, that smog-forming emissions declined during summer as new pollution controls were added to power plants, said AQMD spokesman Sam Atwood.

Summer power plant emission figures were not available Tuesday. Gov. Gray Davis said in a news release last week, however, that power plant emissions are down about 25% statewide as new, cleaner plants have come into service and older ones have been required to clean up.

“The power crisis had little effect on smog,” said Mike Scheible, deputy executive officer for the state Air Resources Board.