Winds with forces of 5 to 6 on the Beaufort scale were wrapped in dust and dominated the sky in China's capital from late Friday until Sunday. Meteorologists said it would end today.

However, cold currents that will hit North China this week might bring more severe sandstorms, they warned.

Reports from the Beijing Meteorological Station said the recent sandstorms were brought by a cold front from Mongolia. It blew fine sand from the Inner Mongolia Autonomous Region and Shanxi and Hebei provinces all the way to Beijing.

Sand and dust used on Beijing construction sites also contributed to the dusty weather, the report said.

Li Sheng, a meteorologist with the station, said high temperatures and less rainfall in North China this winter led to dry topsoil and the sandy weather.

The recent weather is not as serious compared with other sandstorms in the past. The visibility downtown remained at about 1,000 metres, he said.

But he warned that dry soil, and especially the desertification of grazing lands in nearby provinces, might bring more sandstorms this year.

Thirty-two sandstorms swept the countryl last year, he said. Research conducted by the China-Japan Environment Protection Centre showed that some 800,000 hectares of grassland and forest were destroyed between 1995 and 2000 in northern Hebei and the Inner Mongolia, which greatly increased the intensity of sandstorms.

Though the central government had adopted effective measures to plant trees and grass there, it needed more time to take effect.

According to research, sandstorms won't be seeing sharp decreases in the next few years.

To better monitor sandstorms, the central government has established supervision stations in Shanxi, Gansu and Hebei provinces and Inner Mongolia.

These stations monitor sandstorms around the clock, and warn people when one is coming. The entire monitoring and warning programme is expected go into operation later this month.

(China Daily March 18, 2002)