I got this email from a friend at NAU and as I love to watch our very "electrical" monsoons here in N AZ, I found this article pretty interesting.
MILITARY CHAFF MAY BE KILLING VALLEY LIGHTNING
FIBERS SHORT OUT BOLTS, EXPERTS SAYHair-thin fibers released by military jets to evade radar during aerial war
games in southern Arizona may be shorting out spectacular monsoon lightning over Phoenix.
Researchers say the fibers, called chaff, float above the state for up to a
day, forming huge clouds seen only by weather radar and preventing the huge buildup of energy needed to produce lightning.
Routinely released by fighter jets during war games at the Barry M. Goldwater Range, 65 miles southeast of Phoenix, the chaff consists of hair-thin strands of aluminum-coated fiberglass.
Researchers in Arizona have been looking at the chaff-lightning connection
since at least 1990. They took special notice of a strange storm that swept
out of the south and into the Valley on Aug. 20, 1993. The storm pummeled the Valley with heavy rain, hail and powerful winds. There was even a report of a funnel cloud.
But there was almost no lightning.
And lightning almost always comes with strong summer storms in Arizona. But this storm packed just one cloud-to-ground lightning strike. A normal storm of that magnitude could have been expected to produce 35 such bolts, according to Tucson research meteorologist Robert Maddox.
Maddox said he and his colleagues have been perplexed for years over weather records indicating that Phoenix has an unusually low number of lightning strikes for the number of strong monsoon thunderstorms that pass through in July and August.
Maddox took a serious look at the military war games after examining studies conducted 30 years ago by scientists in Boulder, Colo., who experimented with dumping chaff directly into developing thunderstorms.
Maddox, whose research is ongoing, published a study in 1997, and his
colleagues documented 11 potent Valley summer storms from 1995 to 1998 that produced no lightning.
He said that so far, researchers have been focusing on the Valley because it's a "natural laboratory." Summer wind currents blow chaff clear across the Valley, settling out at about the McDowell Mountains.
According to a September 1998 report issued by the General Accounting Office, the investigative arm of Congress, there were 237,975 bundles of chaff released in 1997 during war games at the Goldwater range. There are approximately 2 million fibers per bundle.
http://www.fas.org/man/gao/nsiad-98-219.htm"I think he makes a pretty good case that it is indeed chaff that is causing
the lack of lightning for certain days here in Phoenix," said Randy Cerveny, a geography professor at Arizona State University who specializes in storm
meteorology and Arizona monsoons.
Philip Krider, professor of atmospheric sciences at the University of Arizona,
also is familiar with Maddox's research.
"Looks to me like it's happening," Krider said.
Cerveny said lightning does have beneficial aspects, such as splitting
nitrogen molecules from oxygen molecules and fixing the nitrogen into the
soil.
"This is a major, natural way the earth gets fertilized," Cerveny said.
Cerveny said lightning also corrects an imbalance between positive charges at ground level and negative charges in the cloud. He said there are also studies examining the correlation between lightning strikes and rainfall.
"Right now, we don't know all the ramifications when there's an absence of
lightning," Cerveny said.
https://www.denix.osd.mil/denix/Public/Library/Rfchaff/Docs/military.htmlBy Thomas Ropp, The Arizona Republic, MILITARY CHAFF MAY BE KILLING VALLEY LIGHTNING\FIBERS SHORT OUT BOLTS, EXPERTS SAY., The Arizona Republic, 07-04-1999, pp A1.
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