| Sandstorm thermal structures and atmospheric profiles evolution have been revealed in terms of intensive meteorological elements profiles and energy synoptic meteorology in Minqin; and diagnostic analysis was made by WRF. and temperature, moisture and wind profiles observed Compared with simulated, The results document:(1)Wind speed below 500hPa was week, and there was easterly air flow below 800hPa while westerly on middle-upper layer before sandstorm, the lower layer wind speed increased apparently, northwest air flow below 700hPa and southwest on high-layer. High-layer relative humidity was higher than lower layer before sandstorm, as sandstorm disappeared, relative humidity was gathering speed, Humidity inversion existed near 800hPa, the whole atmospheric humidity increased obviously. Surface temperature was higher before sandstorm, there was a super low temperature phenomena near 200hPa and a downward temperature inversion near 250hPa followed along with sandstorm; during sandstorm, lower-layer temperature dropped markedly, downward temperature inversion was weaker and radiation temperature inversion near 800hPa generated. The atmosphere was convection instability below 500hPa before sandstorm; during sandstorm, saturated energy gap decreased gradually, the instable energy transferred from top to low, vertical movement intensified; after sandstorm, the whole atmosphere was in stability, unstable energy crocked up, the whole atmospheric relative humidity increased greatly.(2) In all simulated atmospheric profiles, temperature profiles came across very well, forecasting deviation was less than 2℃generally, the results of temperature forecasting were also stable with the increase of prediction time; wind profiles showed unstable with the prediction time's growth, the simulated results were poorer below 700hPa; the forecasting deviation of dew point profiles was around 2℃generally while the deviation reached 6℃during sandstorm.
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