The worst of the sandstorms are over for the year, but a few
more are likely to hit southern parts of northwest China's Xinjiang
Uygur Autonomous Region.
"As for Beijing, a city in the shadow of northern China's
frequent sandstorms, the worst period will also to be gone with the
spring," Zhang Guocai, director of the China Meteorological
Administration's (CMA's) Department of Disaster Reduction and
Prediction, said on Thursday in Beijing.
However, he said, the storms remain "an issue darkening the
spring skyline in northern China."
So far this year, China has experienced 17 drifting or flowing
sand weather systems, including one strong sandstorm, five average
storms and 11 drifting or flowing sand phenomena, said Zhang
The March 26 to 30 sandstorm was the worst this spring. It
delayed more than 1,200 flights, including 130 at the Beijing
Capital International Airport, with 20 others forced to land at
airports in Tianjin, Zhengzhou, Taiyuan and Dalian.
A dust storm on March 9 to 11, the largest this spring, swept
more than 19 provinces, autonomous regions and major cities in
north China, as well as areas along the middle and lower reaches of
the Yangtze River.
Zhang reviewed the frequency, features, intensity and impact of
the sandstorms this year, reporting that more occurred this year
than in the same period in 2003.
Recent studies of sunspots found that solar activity affects
sandstorms in China. The storms are likely to increase for a period
around 2030 as solar activity changes, Chinese scientists
predict.
Since 2,000, there have been 67 sand drifting or sandstorm
weather phenomena, with an annual average frequency of 13.4,
according to the CMA.
So far this year, 14 such phenomena have occurred in north,
northwest and northeast China, with less intensity and of shorter
duration than the previous year.
Most took place in March as temperatures climbed rapidly in
north China, running 1 or 2 degrees Celsius above the average. This
led to an earlier thaw of the frozen surface ground, and then a
prolonged dry spell in early spring and cyclones from Inner
Mongolia caused by frequent cold air currents loosened surface
earth and dust.
To mitigate damage, the CMA started daily sandstorm forecasting
in 2001, with early warnings issued through TV, radio and other
media across China.
The CMA can forecast sandstorms three days in advance, Zhang
said.
A national early warning system for large-scale dust and
sandstorms began trial operations this year.
The system consists of 24-hour observation by ground
meteorological stations and remote sensing, and satellite data
transmission.
(China Daily May 21, 2004)