Effect Of Wildfire Smoke On Tahoe Studied

RENO, Nev. (AP) - California's record-setting fire season is giving scientists a chance to study the effect of lingering smoke on Lake Tahoe's environment.

Researchers plan to install a state-of-the-art air sampler to help measure possible toxins being delivered to Tahoe by hundreds of wildfires.

"We're trying to understand the effect of the smoke, not only on the air quality and visibility but also on lake clarity," Tom Cahill, a University of California, Davis professor emeritus of physics and atmospheric sciences, told the North Lake Tahoe Bonanza.

Scientists fear the smoke could deposit loads of nitrogen into Tahoe's waters and diminish its famed clarity by fueling algae growth.

Last summer's wildfire that destroyed 254 homes and scorched 3,100 acres on Lake Tahoe's south shore caused a brief bloom of algae at Tahoe.

Now, reseachers are trying to find out if smoke over a longer period of time has a different effect.

Most of the blazes began during a massive June 21 lightning storm that sparked 800 wildfires across Northern California.

"This is different. The smoke is coming from farther away and it's been here a lot longer," Geoff Schladow, director of the Tahoe Environmental Research Center, told the Reno Gazette-Journal.

"It's been like this for a few weeks now, and it looks like it might be around for a few more," he added.

Scientists have long measured air-borne pollutants at sampling stations at Tahoe City, Incline Village and a buoy in the middle of the lake.

Smoke contains fine particles and nutrients, the biggest enemies to lake clarity.

Scientists are trying to determine what other contaminants might
be in the smoke.

They are particularly interested in polycyclic aromatic hydrocarbons, which are created by the incomplete combustion of trees and brush. Some PAHS can cause cancer in humans.

"These fires may be generating new types of compounds you don't
normally see," Cahill said. "We just don't know. That's the problem."

(Copyright 2008 by The Associated Press. All Rights Reserved.)

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