Despite the decade's strongest sandstorms over the last few days, China's northern areas have not suffered great losses due to the warning provided by the accurate sandstorm forecast.
China's meteorological experts say the forecast, for the first time in domestic meteorological history, gave a precise prediction of the areas to be hit by sandstorms areas allowing sufficient time for protective measures.
It is a notable improvement in China's sandstorm monitoring and early-warning capability, experts say.
According to Ruan Shuigen, official in charge of disaster forecast and alleviation with the China Meteorological Administration (CMA), the central observatory made the tentative forecast almost three days before the strong sandstorm on Wednesday, following which there were two predictions daily with the latest sandstorm information.
Watching closely the dusty weather in northwest China and its rapid movement towards east, forecasters gave a "strong sandstorm warning" on Tuesday morning, an all-time record in China's early-warning history, Ruan said.
Zhang Guocai, general director of the National Meteorological Center (NMC), said that the accurate and early sandstorm forecast can be attributed to the mature satellite remote-sensing monitoring technology as well as to the accumulated experience of forecasters.
According to Dong Chaohua, director of the National Satellite Meteorological Center (NSMC), the monitoring scope of an orbiting meteorological satellite can extend millions of square kilometers, while a photograph taken by an immobile satellite can cover the whole China and her neighboring countries.
The pictures from meteorological satellites can be transmitted to ground within several minutes, which will greatly help the analysis of sandstorm sources, movement and expansion, Dong says.
He also says active cooperation between areas where the sandstorm was expected to start and finish also contributed to the successful forecast. In addition the central observatory intensified contact with the sand source areas prior to the sandstorm.
In addition, the Sandstorm Monitoring and Early-Warning System started last March also played an important role in the forecast of the three sandstorms this year.
Yu Jixin, director of CMA's monitoring network department, said that under this system, the monitoring range has been enlarged with observations of sandstorm-related factors, including water content in different soil depth from zero to 200 centimeters, soil hardness as well as the density of suspended particulate matter in air.
Yu said, the first phase of the system construction is expected to be finished next year with the test and distribution of various scientific facilities almost completed currently.
The completion of the entire system will take three to five years at a cost of 30 million yuan (US$3.6 million).
(Xinhua News Agency March 21, 2002)
