Researchers take to sky to study air pollution

Wednesday, Aug. 10, 2005 | 11:06 a.m.

Researchers are taking to the skies to study pollution above the Las Vegas Valley.

Krys Stave, a UNLV associate professor of environmental studies, has been piloting a sailplane more than 10,000 feet above the valley floor to study ozone pollution in the region. The sailplane is pulled by another aircraft, but once in the air it glides on thermal updrafts, free of mechanical power.

Stave took to the air this morning from the Jean Sport Aviation Center about 30 miles south of Las Vegas. She gathered data as she glided down from above 12,000 feet above the urban area. Researchers from the Desert Research Institute and the National Oceanic and Atmospheric Administration also sent measuring instruments aloft on helium-filled balloons.

"The purpose of the study is to get a profile of the ozone in the near-surface atmosphere," Stave said. "Part of the question is how much ozone is being generated outside of the valley and being carried aloft into the valley in the upper atmosphere."

Finding out where the ozone comes from is a crucial part of understanding the issue of ozone pollution in the region, she explained. The study is part of the Clark County Air Quality and Environmental Management Department's effort to control ozone pollution in the valley.

Besides Clark County, the DRI, UNLV, and NOAA, the University of California-Riverside and the U.S. Environmental Protection Agency are participants in the field research.

The federal government is requiring the region to plan a way to control ozone pollution. Ozone occurs naturally in Earth's upper atmosphere, where it helps protect against harmful ultraviolet radiation. But at ground level, the gas is a key component of urban smog, especially in hot summer months.

Exposure to ozone can cause coughing, wheezing and shortness of breath even in healthy people, and worsen respiratory illnesses such as asthma and bronchitis.

John Koswan, Clark County assistant planning manager, said the multi-agency effort to study the ozone problem is funded with $1 million in county dollars and $400,000 from the EPA. A big part of the ongoing effort is determining how much of the pollution is coming from Southern California.

Until planners understand how much is coming from outside the valley, they will not be able to set limits on how much of the pollutant can be produced locally and stay within federal standards.

"Ozone is a regional pollutant," Koswan said. "There is a role of transport. We have to know what that role is."

But the movement of winds in and around the valley is also important, and that is also part of the research, he said.

Using Stave and her aeronautical skills for the research involved a bit of serendipity. She's been piloting sailplanes for about a year and a half for her personal interest. Stave and fellow enthusiasts are members of the Las Vegas Soaring Association, which owns the sailplane Stave pilots.

Stave was already working with the county on another air pollution project. In a conversation earlier this year with county researchers, her interest and the effort to study ozone came together.

"It was a happy coincidence," Stave said. "The ozone season is really July and August. It was an opportunity that came up and everybody took advantage of quickly."

The measurement instruments themselves are relatively simple, Stave said. An air intake tube comes out through the glider's nose cone. The samples go to a modified plastic tackle box that fits behind the pilot's seat.

The information gathered on her flights is immediately downloaded and available to researchers.

Bob Baxter, the ozone study program manager, is a contractor with Technical and Business Systems Inc.'s office in Valencia, Calif. He said the sampler and data system packed into the tackle box -- a "$5.44 Wal-Mart special" -- as a portable package.

"It was the easiest and lightest weight way to do it," Baxter said.

Researchers have been sending up instruments on weather balloons for several months now, he said, both from Jean and from the North Las Vegas Airport.

"This is just a little different application in that we get it back when we're done," Baxter said. "It is a technology that has been around for a while, but this is a new application."

The sailplane offers some other advantages, he said.

"The sailplane, we viewed it as a platform of opportunity," Baxter said. "But by using a sailplane, there's no engine exhaust. The biggest advantage, though, it that it is a real easy platform to work with."

Dennis Ransel, manager of Clark County's air quality planning section, said the data from the sailplane sampling, the balloon releases and numerous other efforts will be combined in the ultimate regional study. The county will apply the information to its effort to comply with the federal ozone standards.

"Understanding the origins of ozone is our first step towards preparing a plan to control ozone in the valley," he said.