Thanks in part to more favorable weather, Houston finished third in the Smoggiest City sweepstakes behind Los Angeles and the San Joaquin Valley. Take that, LA!
Does this mean the air is cleaner?
Don't hold your breath, the experts say.
The low number of monitors in the Houston area -- 22 in all -- accounts for the underestimation of days when the ozone creeps above the federal health standard, said Bryan Lambeth, senior meteorologist for the Texas Commission on Environmental Quality.
This year the seven monitors that recorded the most days when ozone levels were broken -- five -- were concentrated along the Houston Ship Channel and Loop 610. Last year, Bayland Park in southwest Houston registered 10.
"There are probably more days when ozone exceedances occurred, but we don't know about them. If we added 20 more monitors we'd probably add 20 more days," Lambeth said. "This is one of the quietest years on record, but it's always tough to judge whether the air is cleaner."
The real reason Houston had a more smog-free year was the weather, he said. Sunlight and stagnant air are needed for the air pollutants that create ground-level ozone to react.
The weather in Texas was more rainy and windy than normal in 2002, discouraging ozone formation despite the nitrogen oxides and volatile organic compounds released by Houston's plentiful industry and traffic and its busy port.
Last year, similar weather knocked Houston out of the top spot it had held for two years, a title that heated up the 2000 presidential race and brought criticism on Mayor Lee Brown from some Houstonians who felt that he should have taken a stronger stance against Democrats who lampooned the city's air quality.
Meanwhile, in California, weather patterns and a wildfire season that ranked as one of the worst in history increased smog formation, according to the South Coast Air Quality Management District.
The Los Angeles area recorded 49 days when smog reached levels that can irritate respiratory ailments and make breathing difficult, giving it the smog title for the second straight year, said district spokesman Sam Atwood. The district has 32 monitors measuring air quality around the city.
Atwood downplayed L.A.'s winning record.
"When you guys have a bad year we have a good year, and vice versa," he said. "The typical sunny, Southern California weather is the same pattern that makes for good smog formation."