Abstract:A transfer model is established,which can be used to study the interaction between atmosphere,vegetation and soil. The model is composed of multilayer atmosphere,multilayer soil model and vegetation model which are coupled by balance equation describing the energy and moisture transfer at the interface. A series of tests are preformed to assess the sensitivity of the scheme to the inclusion of variable soil and vegetation characteristics. The results show different vegetation cover,different soil and vegetation types and precipitation exert great influence on energy,water transfer between soil,vegetation and atmosphere. The model developed can be coupled in mesoscale models to study the interaction between land surface processes and the atmosphere in inhomogeneous regions.

Abstract:Based on the analysis about the physical mechanism of drought,a consecutive estimation index of drought has been founded according to the theory of soil water variation. The results show that this method is not only simple for use but also can meet the needs of quantification and real time.

Abstract:General circulation featrues over the Northern Hemisphere in 1997 are analysed. It is shown that the subtropical high over the west Pacific turns stronger,and extends to the west,and at the same time moves northward in the midsummer. At 500hPa,zonal circulation is dominant in the middle latitude of Asia in the most time of the year. Meridinal circulation strengthen during the spring and autumn. Cold air is weaker than normal during the winter and summer. Monsoon over the South China Sea is stronger than normal,monsoon over India is weaker than normal in the midsummer. ITCZ over the west Pacific is werker than normal. At 100hPa,the geopotential height at the mid low latitude is above normal. The location of the South Asia High is farther to the east than normal. A new El Nino event took place in the tropical Pacific region in 1997. the anomaly of both the tropical Pacific and atmosphere circulation exerted a significant impact on the weather and climate in China.

Abstract:Global climate has been warming up persistently in recent years. The year of 1997 was the warmest year throughout the century. The strongest El Nino episode occurred in the central and eastern Pacific and it has a significant impact on world climate. Especially in the tropical regions,extreme climate events such as hot weather and drought,storms and floods frequently occurred,which resulted in severe disaster.During the early winter,cold and snow weather was experienced in Europe and North America. In summer,storms frequently occurred in Europe and central Europe was hit by the century flood. Persistent high temperature weather and drought appeared in northeastern Asia. The western United States was hit by the severest flood of the recent decades,and the border between the USA and Canada was stricken by the severest flood of the recent 100 years.

Abstract:Based on the meteorological data from 336 weather stations,the main features of weather and climate,such as warm winter,hot summer,early spring,less precipitation in the North and more rain in the South,Less and concentrative typhoons landed and so on,are analysed in China in 1997.

Abstract:On the basis of correlative general search,factors are selected by means of optimum category,and the predictands are classified gradually. According to the needs of operation a categorical prediction model is developed,and the results of the model are reasonable both for experimental and for actual forecast.

Abstract:The application of compensation to climate prediction was discussed. It was suggested that compensation was of useful value in anomalous climate and significant weather changes. The compensation concept and applied cases were given.

Abstract:Squall lines which occurred in cold vortexes over Northeast China were analyzed by using data observed at the Harbin weather station and other data sets. The results show that ① The squall lines mostly occurred when the cold vortexes developed strongly and were over the front regions,which had thermodynamically unstable structure. ② There are basically three necessary conditions for the occurrence of squall lines,i.e. unstable thermodynamically structure,convergence of water vapor in the low levels and strong convection.③ A mesoscale weather system occurred near surface. ④ The synoptic scale kinetic energy was transferred to the mesoscale system when the squall lines enhanced.

Abstract:Using the monthly maximum and minimum temperature data in 13 represent ative stations in Qinghai province,the variations of mean monthly,seasonal and year maximum and minimum temperature are analysed. The analysis result shows that there exists an obvious asymmetry variations,especially,obvious anti variatios are seen in March and April. At the same time,urbanization effect on maximurn and minimum temperature are analysed.

Abstract:The Track of Typhoon 9711 and the concomitant raingush in Shandong region were analysed. The results showed that circulaton around the subtropical anticyclone acted as an apparent guidance during the typhoon moving period. The moving track of the typhoon and the rainfall area had strong correlaion with the axes of the positive vortex and of high energy. The distribution of the variable exnergy field in the mid troposphere had an apparent guidance to the typhoon track.

Abstract:According to random sampling data of small Chinese cabbage for different sowing date in Shanghai,leaf ages are estimated by growing model of plant and effective acumulated temperature from 9℃ to 25℃ in the growing period of small Chinese cabbage. Mean absolute error for estimated leaf ages is within half leaf.

Abstract:The relation between death number of emergency treatment and meteorological elements are analyzed by using the successive regression. The result shows that there are anticorrelation between the total death number of emergency treatment of every month and the monthly mean temperature and between that of every dekad and the mean minimum temperature in the same period and positive correlation between that of every month in fall and winter and the monthly mean atmospheric pressure.The major meteorological element which influence the death number of the cerebral angilogical disease and the circulatory system disease of every month is the monthly mean atmospheric pressure,and the relation between them is of positive correlation. The death number of respiratory system disease and the respiration exhaustion is affected obviously by the mean monthly maximum temperature and the monthly precipitation respectively,and the relation between them is of anticorrelation. All regression equations reflect the character that the death numbers of emergency treatment are largest in winter (temperature is lower ,atmospheric pressure is highest,and precipitation is smallest.) and least in summer (temperature is highest,atmospheric pressure is lower,and precipitation is most).