Abstract:The mainly factors of the drought causing disaster are analysed. The results show that the drought disaster occurring mostly depends on the states of the crop water requirement and the environment water supply. The precipitation variability,the water store in soil layers,the crop response on rainfall deficit in the different growing period and hum.an activity influence on the drought disaster. Because the crop sensibility to water in the growing periods are different, the complex evaluation is conducted according to the rainfall deficit, the deficient duration and the crop sensibility to water during the deficient rainfall. The complex index evaluating the drought disaster is also given.

Abstract:The subject is to study an example of special sandstorm occurred in Gansu province viith recursive similarity. The jump was defined as the level that the preceding numbers of R data could not completely describe the present state. The results indicated that every element violent wave at 16 o'clock was not the larger jump value in recursive similarity,the larger values were occurred before 16 o'clock. At last,The formal abrupt and essential abrupt were presented.

Abstract:Greenness image of NOAA/AVHRR is the base and its processing is the key technology of crop yield estimation with remote sensing. A new edition of Greenness Image Processing System (GPS2. 0) is developed to innovate its software. A brief presentation to GPS2.0's overall design, running environment,functions and methods of processing greenness image is also given.

Abstract:By Analysing and comparing the advantages and shortcomings of traditional Video Preparation System, Tape Digital Preparation System and Multimedia System, this article puts forward the proposal of how to choose the installation in provincial and local weather forecast processing system.

Abstract:The distribution and Variation Characteristics of the Sea level, Southern Oscillation Index the zonal wind in lower and higher level, the outgoing long-wave radiation, the Sea temperature were analysed based on the recent data of National Climate Center in China, Climate Analysis Center U. S. and Nation Climate Center Australia. It provides atmaspheric-ocean background for the short-range climatic prediction.

Abstract:Utilizing the data of the monthly sunshine hours in Neijiang stations in 1960—1995, the change characteristics of the sunshine hours about recent fourty years in Neijiang municipality are analysed, and the sunshine average hours in the area is decreasing at the trend rate of —46.98 hours/10 years. This kind of tendency appears mainly in winter and Summer Meantime, it was pointed out that the sudden change of sunshine hours occured in Neijiang in 1980,and then there is a relative less hours period.

Abstract:Selected 586 cases producing shaanxi heavy rain weather during April to Nevember in 1961—1988 ,every case is summarized to a series rain index and a similarity historical sample,using the expert forecasting experiences and multivariate similarity, the short-range heavy rain of shaanxi in limited erea is forecasted. The accuracy of forecasting can reach to 78% during July to August in 1989.

Abstract:The characteristics of rainfall,macro-physical parameters of cloud and the relations of cloud and rainfall are studied. The precipitation enhancement potencies of main weather systems range from 42. 55% to 68. 79%. Elaborated, also is the possibility of exploiting cloud-water resources by rain-making with aircraft. The scientific verification for cloud seeding in the coastland of Shandong province are provided by the analysis of water vapor vertical distribution.

Abstract:The basic construction and principle of RS-1 airborne AgI generator is described. The maintain methods of the generator units are given. The electric road of the controller is improved.

Abstract:In the Agriculture Meteorological Rule, it was prescribed that the field calibration must be done before the soil moisture is measured by the Neutron Soil Moisture Meter. It was found in practice that calibration method is very difficult and has a time limitation and objective error. The questions can best be solved with dividing calibration time and changing calibration place.

Abstract:In order to guarantee the long term operation of microcomputer system reliably and stably, the maintenance methods are discussed,e. g. keeping good environmental conditions,being familiar with the correct usage and taking good care of the machine daily.

Abstract:By use of 45 stations data in Shandong Province and in the centre of Shaanxi Province and the Euclidean distance method,the agroclimatic analogue diagnosis of introduced variety of winter wheat was conducted,the results showed:a)the super-ear wheat varieties can be introduced directly from the central section in Shaanxi Province in the most of Shandong Province:b) because of planting wintriness and semi-wintriness wheat varieties in Shandong,the super-ear wheat variety from Xianyang may be planted in warm winter years, to avoide freezing injury and give the high yield superiority.

Abstract:A spline regression model was used to describe the relationship between the leaf age and the accumulated effective temperature, based on analysing the change of leaf age of winter wheat during the pre-and post-overwinter period. Interpolation of leaf age data was made and the optimal seeding date was decided with this model.