Spatial And Temporal Distribution And Variation Trend Of Cloud, Precipitation And Precipitable Water Of Inner Mongolia And The Relationship Between Them And Climate Factors

Inner Mongolia is a big province in developing weather modification work. Its features are earlier, more methods, larger area, longer time. But this work exists of blindness for a long time. Its operational object is cloud;the purpose is to develop water sources of sky and increase rainfall. And it is concerned that climate change may affect cloud and precipitation as well as its feedback. So the studies about these in Inner Mongolia have been done.In this thesis, studies are conducted by using trend analysis and statistical method. The spatial and temporal distribution of nineteen kinds of cloud amount parameters, precipitation and precipitable water in Inner Mongolia are analysis. Features of precipitus, synopitic system, and precipitation type and precipitation intensity in middle of Inner Mongolia from March to August are analysed. Features of hail in Huhhot are analysed. Temporal distribution and variation trend of climatic factors are analysed. All of these studies are based on the data that include the cloud climate data in newest D2 data bank of ISCCP, surface observation data of four times per day and daily 24-hour precipitation of 25 stations in the middle of Inner Mongolia, month precipitation of 117 stations in Inner Mongolia, sounding data of 12 stations, nine climatic factors form 1951 to 2003, and hail data in Huhhot. The surface observation data of four times per day include historical weather map, cloud amount, cloud form, sixteen weather phenomenon. There are some main conclusions as follows:1, In Inner Mongolia, Mean cloud amount, low cloud amount, middle cloud amount , liquid stratocumulus liquid stratus, ice stratocumulus, ice stratus, ice nimbostratus cloud amount are getting more from west to east. High cloud amount, cirrostratus, deep convective cloud amount are getting fewer from southwest to northeast. The variation trend of mean cloud amount increases at east of Inner Mongolia and decreases at middle and west of Inner Mongolia. It has especially been done to analyse the spatial and temporal distribution and variation trend of different kinds of cloud amount parameters as well as the relationship between them and climate factors.2 ^ Precipitation is getting more from west to east in Inner Mongolia. Precipitation trend is increasing at middle and decrease at east of Inner Mongolia. Frequency of precipitous in middle of Inner Mongolia is getting more from west to east. The effect of precipitation cloud is different at different area in Inner Mongolia. Precipitation type in middle of Inner Mongolia is persistence in spring and shower in summer. The hail day's trend in Huhhot area is of increase from 1969 to 2000.3 -> There is positive correlation between area precipitation and liquid cloud amount, A^ B index of Qing-zang Plateau ,the index of the Northern Hemisphere pole eddy intension, subtropical high pressure intension index, subtropical high pressure area index respectively. But there is negative correlation between area precipitation and ice cloud amount, Asia longitude circumfluence, Asia latitude circumfluence index, the Northern Hemisphere pole eddy area index respectively.4n In Inner Mongolia precipitable water is getting more from west to east, The changing trends of perceptible water at twelve stations are increasing from 1980 to 2000, it seem as the trends of Qing-zang Plateau B index, subtropical high pressure intension index, subtropical high pressure area index. Generally speaking,rainfall effectiveness of Inner Mongolia is lower.These research results can provide scientific foundations for setting down project, preparing equipments, forecasting and choosing condition, and guiding real weather modification works at Inner Mongolia. It has practical meaning.