Abstract: The multiscale meteorological characteristics during a strong sandstorm in Minqin on 27 March,2007 were analyzed using the data from Minqin Meteorological Station. The results were as follows: ① It was obvious that the development of meteorological elements was characterized by the multiscale variations in surface layer during the strong sandstorm. Specifically,there were two main periods of wind speed near the surface,and they were for 2.5 hours and 1 hour respectively,which was the same as the disturbed temperature at 20 m height.Different from wind speed and disturbed temperature,the period of PM₁₀ concentration was for 1.5 hours,and there was a period of relative humidity longer than 3.5 hours; ② Wind speed signal on a scale about 1 hour occurred 3 hours earlier than that on a scale about 2.5 hours,which revealed that an adverse scale development of wind speed was apparent during the sandstorm.Compared with the signals of wind speed and PM₁₀ concentration,the perturbed temperature signal on a scale about 1 hour emerged earlier and its intensity reduced when the sandstorm occurred; ③ It was found that the wind speed signal varied synchronously with the change of PM₁₀ concentration signal during the sandstorm,however,its variation over the time was not synchronous with the disturbed temperature signal,which probably meant that the development of gravitational wave played a critical role in sand raising.

Key words: sandstorm, wavelet analysis, time series, time scale, Minqin