China dust cloud circled globe in 13 days

[Cees Binkhorst]

REPLY TO: D66 at nic.surfnet.nl

Kennelijk zorgen de Chinezen goed voor de algen in de Pacific ;)

Nu de kwaliteit van de Gele Zee nog. Beetje minder vervuiling.

Groet / Cees

http://www.portfolio.com/business-news/reuters/2009/07/20/china-dust-cloud-circled-globe-in-13-days
China dust cloud circled globe in 13 days
Jul 20 2009 1:09PM EDT

HONG KONG (Reuters) - Dust clouds generated by a huge dust storm in
China's Taklimakan desert in 2007 made more than one full circle around
the globe in just 13 days, a Japanese study using a NASA satellite has
found.

When the cloud reached the Pacific Ocean the second time, it descended and
deposited some of its dust into the sea, showing how a natural phenomenon
can impact the environment far away.

"Asian dust is usually deposited near the Yellow Sea, around the Japan
area, while Sahara dust ends up around the Atlantic Ocean and coast of
Africa," said Itsushi Uno of Kyushu University's Research Institute for
Applied Mechanics.

"But this study shows that China dust can be deposited into the (Pacific
Ocean)," he told Reuters by telephone. "Dust clouds contain 5 percent
iron, that is important for the ocean."

In a paper published in Nature Geoscience, scientists described how they
used a NASA satellite and mathematical modeling to track and measure the
movement of the dust cloud, which formed after the dust storm on May 8-9
in 2007.

The desert is in the Chinese northwestern region of Xinjiang.

The researchers, led by Uno, found that the dust clouds were lifted 8-10
km (5-6 miles) above the earth's surface, and transported more than one
full circle around the earth.

"The most important achievement is that we tracked this through one full
circuit round the globe, nobody has done this before. After half a
circuit, usually the dust concentration gets very low and you can't track
it," Uno told Reuters.

"This means that dust concentration, dust lifetime is very long, more than
two weeks."

The dust cloud measured about 3 km (1.9 miles) vertically and up to 2,000
km horizontally and it stayed that way even after one full trip around the
globe.

"The reason why the cloud structure was very well maintained was because
the dust was uplifted ... where the atmosphere is very stable," Uno said.

Researchers believe dust particles trigger the formation of high-altitude
cirrus clouds -- although experts have no idea whether such clouds warm or
cool the earth.

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