A 10-year study on sandstorms has cast new light on the origins and movements
of the dusty phenomenon.
The storms are closely related to Siberian cold fronts, and come along three
different routes, said Kang Ling, deputy director of the Observatory of the
Inner Mongolia Autonomous Region.
In the eastern route, the front runs southward through central and eastern
Mongolia, affecting Northeast China, central and eastern Inner Mongolia, Shanxi
and Hebei provinces.
The central route is southward through central and western Mongolia,
affecting central and western Inner Mongolia and eastern areas of Northwest
China, central and southern parts of North China.
To the west, the front blows southward through western Mongolia and northeast
Kazakhstan, affecting western parts of China, and areas of North China.
"Most of the sandstorms sweeping Beijing and Tianjin this year came from
abroad and mainly through the central route," Kang said in a Xinhua report.
Statistics indicated that at least 11 major sandstorms hit North China during
the past two months, making it "the worst sandstorm weather in the spring season
for a decade." What's worse, meteorologists predicted more storms later this
month.
Researchers from the China Meteorological Administration, Kang's observatory
and the China-Japan Friendship Centre for Environmental Protection participated
in the research programme.
Satellites, remote sensing, radar and other high technologies were used to
study the source regions, routes and the influence on Beijing..
Kang said some of the sandstorms originated in China and others came from
abroad.
"Desert is the major source of sandstorms," said Zhang Xiaoye, head of the
Chinese Academy of Meteorological Sciences. "Sandstorms will not disappear until
the deserts totally vanish."
Statistics indicate that China has 1.67 million square kilometres of desert.
Traditional farming methods in northern parts of the country also have an
influence, experts said.
"The dry and vulnerable topsoil in North China can easily be picked up and
carried by the wind," said Jin Heling, an expert with the Institute of
Environment and Engineering in Cold and Arid Regions under the Chinese Academy
of Sciences.
"Sandstorms are usually triggered by sudden temperature changes in
springtime, poor vegetation cover and aridity. However, exposed plough land
where soil can be blown away is also a major cause," said Kang.
Meteorologists suggested that a protective forest be established around
Beijing and Tianjin and more trees be planted in Inner Mongolia to curb
desertification.
Since the late 1990s, the Chinese Government has invested heavily in the
implementation of the Sandstorm Source Control Project in and around Beijing and
Tianjin.
To date, the government has invested 55.8 billion yuan
(US$6.9 billion) in various projects, including tree planting. One-fourth of the
programme has been finished and one-seventh of exposed land made
green.
