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"On my part, I remain committed to the process of dialogue. It is my firm belief that dialogue and a willingness to look with honesty and clarity at the reality of Tibet can lead us to a viable solution."

UN: Clouds of pollution threaten glaciers, health

November 15, 2008

The Associated Press
November 13, 2008

BEIJING (AP) -- A dirty brown haze sometimes more than a mile thick
is darkening skies not only over vast areas of Asia, but also in the
Middle East, southern Africa and the Amazon Basin, changing weather
patterns around the world and threatening health and food supplies,
the U.N. reported Thursday.

The huge smog-like plumes, caused mainly by the burning of fossil
fuels and firewood, are known as "atmospheric brown clouds."

When mixed with emissions of carbon dioxide and other gases blamed
for warming the earth's atmosphere like a greenhouse, they are the
newest threat to the global environment, according to a report
commissioned by the U.N. Environment Program.

"All of this points to an even greater and urgent need to look at
emissions across the planet," said Achim Steiner, head of Kenya-based
UNEP, which funded the report with backing from Italy, Sweden and the
United States.

Brown clouds are caused by an unhealthy mix of particles, ozone and
other chemicals that come from cars, coal-fired power plants, burning
fields and wood-burning stoves. First identified by the report's lead
researcher in 1990, the clouds were depicted Thursday as being more
widespread and causing more environmental damage than previously known.

Perhaps most widely recognized as the haze this past summer over
Beijing's Olympics, the clouds have been found to be more than a mile
thick around glaciers in the Himalaya and Hindu Kush mountain ranges.
They hide the sun and absorb radiation, leading to new worries not
only about global climate change but also about extreme weather conditions.

"All these have led to negative effects on water resources and crop
yields," the report says.

Health problems associated with particulate pollution, such as
cardiovascular and respiratory diseases, are linked to nearly 350,000
premature deaths in China and India every year, said Henning Rohde, a
University of Stockholm scientist who worked on the study.

Soot levels in the air were reported to have risen alarmingly in 13
megacities: Bangkok, Beijing, Cairo, Dhaka, Karachi, Kolkata, Lagos,
Mumbai, New Delhi, Seoul, Shanghai, Shenzhen and Tehran.

Brown clouds were also cited as dimming the light by as much as 25
percent in some places including Karachi, New Delhi, Shanghai and Beijing.

The phenomenon complicates the climate change scenario, because the
brown clouds also help cool the earth's surface and mask the impact
of global warming by an average of 40 percent, according to the report.

Though it has been studied closely in Asia, the latest findings,
conducted by an international collaboration of scientists, reveal
that the brown cloud phenomenon is not unique to Asia, with pollution
hotspots seen in North America, Europe, South Africa and South America.

More specifically, researchers found, brown clouds are forming over
eastern China; northeastern Pakistan, India, Bangladesh and Myanmar;
Cambodia, Indonesia, Thailand, and Vietnam; sub-Saharan Africa
southward into Angola, Zambia and Zimbabwe; and the Amazon Basin in
South America.

The enormous cloud masses can move across continents within three to
four days. Although they also form over the eastern U.S. and Europe,
winter snow and rain tend to lessen the impact in those areas.

An international response is needed to deal with "the twin threats of
greenhouse gases and brown clouds and the unsustainable development
that underpins both," said the lead researcher, Veerabhadran
Ramanathan, a professor of climate and ocean sciences at the
University of California in San Diego.

One of the most serious problems, Ramanathan said, is retreat of the
glaciers in the Himalaya and Hindu Kush and in Tibet. The glaciers
feed most Asian rivers and "have serious implications for the water
and food security of Asia," he said.

Monsoon rains over India and southeast Asia decreased between 5 and 7
percent overall since the 1950s, the report says, naming brown clouds
and global warming as a possible cause. Likewise, they may have
contributed to the melting of China's glaciers, which have shrunk 5
percent since the 1950s. The volume of China's nearly 47,000 glaciers
has fallen by 3,000 square kilometers (1,158.31 square miles) in the
past 25 years, according to the Chinese Academy of Sciences.

Soot winds up on the surface of the glaciers that feed the Ganges,
Indus, Yangtze and Yellow rivers, which makes the glaciers absorb
more sunlight and melt more quickly and also pollutes the rivers, the
researchers say.

But the U.N., which began studying the problem six years ago, still
finds "significant uncertainty" in understanding how brown clouds
affect conditions regionally, Ramanathan cautioned.

Associated Press Writer John Heilprin contributed to this report from
the United Nations.
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