[AZ-Observing] The Disappearance of Arizona's Famed Dark Skies
- From: Stan Gorodenski <stanlep@xxxxxxxxxxxxx>
- To: AZ-Observing <az-observing@xxxxxxxxxxxxx>
- Date: Sun, 31 Aug 2008 07:31:03 -0700
Remember some time ago I speculated Arizona's famed astronomical skies
would disappear some time in the future because of pollution from
China-Asia. I read this in Yahoo this morning. Very disturbing.
Naturally, because of our dependence on China for financing our deficit,
poor economy, and influence by corporations, Washington will lack the
guts to take necessary measures internationally to protect our health
from pollutants like mercury.
Stan
WASHINGTON — From 500 miles in space, satellites track brown clouds of
dust, soot and other toxic pollutants from China and elsewhere in Asia
as they stream across the Pacific and take dead aim at the western U.S.
A fleet of tiny, specially equipped unmanned aerial vehicles, launched
from an island in the East China Sea 700 or so miles downwind of Beijing
, are flying through the projected paths of the pollution taking
chemical samples and recording temperatures, humidity levels and
sunlight intensity in the clouds of smog.
On the summit of 9,000-foot Mt. Bachelor in central Oregon and near sea
level at Cheeka Peak on Washington state's Olympic Peninsula , monitors
track the pollution as it arrives in America.
By some estimates more than 10 billion pounds of airborne pollutants
from Asia — ranging from soot to mercury to carbon dioxide to ozone —
reach the U.S. annually. The problem is only expected to worsen: Some
Chinese officials have warned that pollution in their country could
quadruple in the next 15 years.
While some scientists are less certain, others say the Asian pollution
could destabilize weather patterns across the North Pacific, mask the
effects of global warming, reduce rainfall in the American West and
compromise efforts to meet air-pollution standards.
" East Asia pollution aerosols could impose far reaching environmental
impacts at continental, hemispheric and global scales because of
long-range transport," according to a report earlier this year in the
Journal of Geophysical Research . The report said that a "warm conveyor
belt" lifts the pollutants into the upper troposphere — the lowest layer
of Earth's atmosphere — over Asia , where winds can bring it to the U.S.
in a week or less.
The National Academies of Science, at the request of the Environmental
Protection Agency , NASA , the National Oceanic and Atmospheric
Administration and in consultation with the State Department , has
assembled a panel to examine the problem and its impact. Its report is
due next summer.
"Everyone realizes this is an issue of growing importance," said Laurie
Geller of the National Academies of Science. "This is very challenging
science with lots of complexities and a lot of uncertainties."
Though the problem of Asian air pollution has been known for years, no
one has a handle on how much is blown in and what it includes.
Scientists say Washington state and Oregon might be feeling the brunt of
the effects.
"This pollution is distributed on average equally from northern
California to British Columbia ," said Dan Jaffe , a professor of
environmental science at the University of Washington's Bothell campus.
"Anyone who has gone out to measure it has found something."
Particulates such as dust and soot, along with heavy metals, pesticides,
PCBs, mercury, ozone, carbon dioxide, nitrogen dioxide and sulfur
dioxide have all been found. Jaffe said the pollutants can't be tracked
to a single source such as a particular coal-burning plant, but their
"chemical fingerprints" can point to a specific country.
Viruses, bacteria and fungi also can be transported on dust particles,
though, so far, they've been found only on the dust and sand blowing off
African deserts, not Asian ones.
Mercury, one of the most hazardous pollutants from the hundreds of
coal-burning electricity generating plants in China and elsewhere in
Asia , is of particular concern. One study estimated a fifth of the
mercury entering Oregon's Willamette River comes from overseas, with
China as the mostly likely source.
Jaffe, a member of the National Academies of Science panel studying the
issue, is wary of such reports. But he still estimates that as much as
30 percent of the mercury deposited in the U.S. from airborne sources
comes from Asia , with the highest concentrations in Alaska and other
western states.
"Ten years ago, there was a lot of skepticism," Jaffe said. "People
assumed the atmosphere scrubbed itself and didn't believe these
pollutants could travel thousands of miles."
The pollution from Asia will only make it increasingly difficult for the
U.S. to meet stricter and stricter air quality standards, said Lyatt
Jaegle, a professor of atmospheric sciences at the University of
Washington in Seattle .
"It is only expected to get worse," Jaegle said of the Asian air
pollution reaching the U.S. She added that scientists have discovered
the problem isn't unique to the Pacific Rim . "Air pollution is not a
local or regional problem, it is a global problem."
Days after a major dust storm in the Gobi Desert in Asia , visibility in
the Grand Canyon was obscured. Dust from deserts in North Africa has
reached Florida . U.S. air pollution can reach across the Atlantic to
Europe , even as pollution from Europe can circle the globe and reach
the U.S.
Air can circulate around the world in three weeks or less. The National
Academies of Science is not limiting itself to pollution from Asia and
will study the phenomenon worldwide.
"It's one atmosphere," said Mark Schoeberl , project scientist for NASA
Aura satellite program.
Schoeberl said his and other satellites have "transformed" what
scientists know about the Earth and can provide a near real-time
snapshot of the track of airborne pollution. When the price of gasoline
spikes, Jaffe said satellites can detect an increase in sulfur dioxide
levels at Saudi Arabian refineries . They've also helped confirm global
dimming as sunlight reaching the planet's surface is decreasing because
the airborne pollution reflects it back to space. In some places, like
Israel , sunlight has decreased 10 percent, Jaffe said.
The pollution also can mask the effect of global warming by reflecting
the sunlight, said Veerabhadran Ramanathan, a climate researcher at the
Scripps Institution of Oceanography in California who's heading the team
of scientists flying the unmanned aerial vehicles off Korea this summer.
The UAVs started flying as China shut down factories and banned
automobiles from Beijing during the Summer Olympics and are still flying
as pollution levels increase.
"It's a once in a lifetime opportunity," Ramanathan said.
The reduction in sunlight could be increasing rainfall or it might be
decreasing rainfall because of less evaporation off the ocean,
Ramanathan said. In addition, the soot falling on mountains in the
western U.S. could increase snowmelt, he said.
"There are a lot of questions and few answers," Ramanathan said. "We
shouldn't be pointing fingers. Everyone else is some one else's
backyard. This is a global problem."
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