The relationship between dust storm days in ShanxiProvince and precipitation inMongolia, snow days on Qinghai-Xizang Plateau, snow days in northern China, circulation factors such as SOIwas analyzed in this paper. Results show that the quasi-periodic variation of global atmosphere and oceans plays an important role in development and change of dust storm events. Precipitation in the lastyear in thewestofMongolia is an indicator fordust storm weather in ShanxiProvince. There exists significantnegative correlation between yearly duststorm days in Shanxi and snow days in previouswinteron theQinghai-XizangPlateau and in InnerMongolia.Two years lag positive correlation between duststorm days and SOI index is also found. Stationswith significantcorrelationwith SOI index are generally located in the central and eastern parts ofShanxiProvince. Based on the correlation analysis, a conceptionmodel is put forward, and a prediction equation is builtby using stepwise linear regressionmethod. It could be used in prediction ofdust storm frequency in ShanxiProvince.

Using daily p recip itation data of 41 meteorological stations in CentralNorth China from 1961 to 2005 and the extreme p recip itation indices developed byWMO /CCL and CL IVAR, the temporal and spatial characteristics of extreme p recip itation events change was analyzed. Results show that the annual average maximum daily p recip itation p resented a decreasing trend in centralNorth China,but the average heavy and extreme rainfall days changed indistinctively; the days and intensity of heavy rainfall increased obviously in the middle and late 1990 s’; there was a significant drop in rainfall days, especially in the south and southeast region, but no significant change in rainfall intensity. These imp ly that the p roportion of the extreme p recip itation events in the total rainfall days increased,and the p roportion of extreme p recip itation amount in the total annual p recip itation might increase also in the period 1961 - 2005 in the researchregion.