GIFT FROM LA NINA: LESS SMOG; OZONE LEVELS LOWER DUE TO COOLER TEMPS.

Byline: Charles F. Bostwick Staff Writer

Antelope Valley residents have enjoyed much cleaner air so far this summer, thanks to the La Nina weather pattern and cooler temperatures.

On only one day have ozone levels exceeded the state government's air quality standard, compared with 31 days by this time last year.

``That's much better weather,'' said Tony Malone, an air quality technician for the Mojave Desert Air Quality Management District, which maintains air monitoring equipment for the Antelope Valley Air Quality Management District.

The cooler weather is due to the La Nina weather pattern, plus a shift in the jet stream that brought cooler Alaska air to California, he said.

In July 1999, the temperature at the Lancaster monitoring station never got to 100, compared with a high temperature of 107 in July 1998.

The smoggiest day was June 29, when ozone levels reached an 83 pollution standard index (PSI), the state standard.

Ozone reached or exceeded 83 on 31 days by this time last year and reached the more lax federal standard of 100 on eight of those days. Last year was the smoggiest in the Antelope Valley in three years, blamed on a summer that was warmer than in recent years.

The sun's heat cooks up industrial and automotive pollutants and creates ozone, the smog component that causes eyes to burn and lungs to ache.

But even last year's air quality was far better than it was as recently as 10 years ago.

The Antelope Valley's record smog year was 1981, when ozone failed federal standards 82 days, state standards 133 days and set off seven Stage 1 alerts. From 1977 through 1981, Antelope Valley residents endured one or more days of Stage 1 smog alerts annually - including seven days each in 1980 and 1981.

The Antelope Valley's last Stage 1 alert was in 1989.

Local ozone levels exceeded federal health standards on only one day in 1996, none in 1997.