Variation characteristics of meteorological factors during dust storm at Dunhuang, China

Dunhuang as characterized during spring with considerable strong Winds is one of the regions in China where an average of 14 dust storms per year occurs and passes. Agriculture, economy, human health and global climate are seriously affected by dust storms, which are the largest source of aerosols. Nowadays, satellites and numerical models track the intercontinental transport of dust particles. To contribute in the data input, parameterization, and verification of a dust outbreak model, meteorological observations were started at Dunhuang in spring 2001. In this region, dust concentration index (DCI) has been collected as a measure for dust concentration in the air. Likewise, meteorological parameters are being measured simultaneously. Initial analyses of data from 2001 to 2004 showed that frequency of dust storm that passed by, originated from or settled down the station varied for each year. During dust storm, meteorological variations exhibited similar pattern, but wind speed and DCI profiles depended on the type of dust storm. Furthermore, different relationships could be established between vertical properties DCI, wind speed, friction velocity, and roughness length. The most reliable being that DCI and roughness length increases exponentially with strong wind speed (greater than 6 m/s at 10 m-level). Further analyses including 2005 data are still needed to be more accurate and confident in establishing parameter relationships as inputs for the dust outbreak model.