China dust cloud circled globe in 13 days

http://www.reuters.com/article/scienceNews/idUSTRE56J3YH20090720

Mon 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."

.....

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.