Research On Characteristics Of Climate And Forecasting Model For The Snow Disasters In The Prairie Of Northwest Sichuan

Based on the sum of thirty-nine year's snow disasters case data in 1967-2005 and the sum of thirty-four year's conventionality observation data, analyzed to snow disasters and characteristics of climate's space-time distributing, opened out theirs relativity. Resulted out the prairie snow disasters in the northwest of Sichuan mostly appearing from February to April, trend of snow disasters happened times and intensity year's variety is declined, the year's variety trend of the mean annual temperature and mean surface temperature in winter half year is rised, snow disasters happened times and intensity to the mean annual temperature in winter half year 's relativity is difference, to the total precipitation in winter half year is positive correlation. But the total trend of snow disasters happened times and intensity year's variety is rised before 1985, opposition after 1985. The year's variety total trend of the mean annual temperature is declined before 1983, opposition after 1983. The snow disasters happened times, intensity, the total precipitation in winter half year is not year's variety periods, year's variety of the mean annual temperature in winter half year is variety periods at from 9 year to 12 year, year's variety of the mean surface temperature in winter half year is variety periods at 13 year. The main weather process happened snow disasters is code wave, series cloudy sky snow and heavy snow, thus analyzed to classify the snow disasters cause of formation and case data, opened out the moving path of Ural anticyclonic ridge, Ural hovmoller, zonal circulation and cold air happened the prairie snow disasters in the northwest of Sichuan. Depend on the characteristic of plateau snow disasters, relativity climate circulation character and weather element guide line to establish long-range, extened, short-term forecasting model, which is fetched good effect in the practice forecast.