Abstract:The relationship between the east Asian monsoon(EAM) and ENSO events is different on the different interdecadal background in SST fields. The largest anomaly center of precipitation locats in the south side of the Changjiang river in the next summer of ENSO events on the cold SST interdecadal background, with its counterpart in the Huanan area in the next Spring on the warm background. The temperature variation is not corresponding to the rainfall. The interdecadal background of SST affects the air sea heat flux exchange and the thermal contrast between land and ocean, thus changing the monsoon intensity and the relation of ENSO and EAM.

Abstract:Algorithms for iteratively refining the parameter estimates and residuals from the fitting of a regression model using QR decomposition are described. It is shown that, if algorithms for performing the QR decomposition are free from calculation of square root, the related iterative refinement algorithms can also be square root free. Verification of the algorithms is carried out and comments are made on the accuracy of parameter estimates.

Abstract:The long-term trend and oscillations of Lanzhou temperature over recent 64 years are detected by using the singular spectrum analysis. Results show that there is a general warming all over the period. The amplitude of interdecadal oscillations is large, with a cooling of 1℃ from 1946 to 1967 and a warming of about 1.3℃ from 1968 to the earlier mineties. There are also interannual and intermonthly oscillation periods of 7.5- year, 3.3-year, 7.69-month, 3.38-month. Since 1976 strong changes in seasonal cycle have taken place, with winters becoming warmer and summers colder. The annual range of monthly mean temperature in the latest 21 years was 1.7℃ less than in the earlier 43 years. The monthly mean temperature anomaly for 4 months extension may be predicted by using SSAMEM.

Abstract:Dry matter accumulation is basis for yield formation of rice. In this paper, it was theoretically calculated following the principle of crop growth simulation in the context of experimental data of staging sowing and corresponding temperature and sunshine hours. Temporal change and geographical distribution were analyzed and regionalization was made for the dry matter accumulation, which may be valuable for study of ecological condition for yield formation of rice.

Abstract:In this paper, statistical models for growing rate, yield and yield percentage prior to frost arrival were established and verified for film-covered cotton crop based on the five-year staging-sowing experiment from 1991 to 1995. Concerned agrometeorological indices were also derived and examined against the real data. Taking climatic data and grid interpolated one in every place of Ningxia from 1961 to 1990 as inputs to the models, growing process of the cotton, yield and yield percentage prior to frost arrival were modelled and their probability distributions were computed and drawn. Finally, the preference degree of planting film-covered cotton was analyzed and regionalized in the Ningxia.

Abstract:Taken into consideration are topographical features, ratio of rice planting area to total, agroclimatic type and vegetation regime, a general-regionalization and multi-hierar-chy-decision model is established for estimation of rice planting area through remote sensing and some quantitative relationships are demonstrated based on analytic hierarchy process. By making use of remote sensing and taking advantage of geographical information system (GIS) in spatial analysis, the composite natural demarcation of rice planting area was achieved for Zhejiang Province.

Abstract:Two heavy rain cases are simulated with the PSU/NCAR mesocale model.For control experiments,both the surface and upper air observation are used in the initial fields.For sensitive experiments,the initial fields are the same with the control ones,but the real time GMS satellite convective cloud cluster data are used to modify the initial moisture fields.The results show that (1)because the convective cloud data strengthen local moisture fields,both the convergence and updrafts of the low-middle troposphere over the heavy rain center and its peripherial areas intensify and reach maximum in strength about fourth hour in sensitive experiments;(2)because of the use of convective cloud data,the simulated rainfall in the first 4～6 hours is greater than that in the control experiment,and it is closer to the real rainfall;(3)if the modified initial moisture field is initialized with the other initial fields,then the duration of humidity effect is greatly extended.

Abstract:The Monte Carlo simulation is applied to an air-sea coupling stochastic dynamic model with threshold in this paper. The prediction error is defined by means of the concept of phase space,the best choice tests are made for probability density functions of initial stochastic perturbations of different phase space variables as well as for the ensemble sample size of Monte Carlo simulation . The results show that the zero mean Grass distribution is the best for the probability density functions of initial stochastic perturbations and the ensembe sample size N =32 is optimal .The forecast skill for different forecast methods is examined by the climatic persistence forecast.The test results of 1982～1983 and 1986～1987 ENSO events show that the Monte Carlo ensemble prediction is superior to any single stochastic dynamical models in smoe extent,and its forecast effect is totally superior to the climatic persistence forecasts.

Abstract:The vertical structure of the low-frequency variations of the temperature fields from the troposphere to the lower stratosphere over the eastern part of the Qinghai-Xizang Plateau is studied in this paper using the single correlation method. The seasonal variation features of the height and intensity of maximum negative correlation layer are pointed out,and are compared with circumstances at Geermu in the northern part of the plateau and in the northern region of China (120 °E,30～50 °N). The physical reasons for the low-frequency vertical structure and seasonal variations of the temperature fields over the Qinghai-Xizang plateau is discussed in terms of seasonal changes of the tropopause, atmospheric temperature stratification and vertical profiles of kinetic energy over the plateau. At last, it is investigated and pointed out that the Autumn(October-November )atmospheric thermal structure over the eastern part of the plateau and the intensity of two Walker circulation cells over the equatorial Indian Ocean to the equatorial Pacific ocean are closely related with the SSTA(0～10 °S,180～90 °W )from October to January.

Abstract:A type of survey instrument with a mixed bar-point and digital display function is developed based on a piece of AT89C2051 microcontroller. The software and hardware used is presented in detail and the method for multiple simulative serial port data transmission over a public line is also given. Because the design makes full use of the microcontroller’s software and hardware resources, the resulted instrument has an integrated function to display in form of both digits and a 2-channel bar consisting of up to 128 points, to work for control and communication, and to be easily extended.

Abstract:The paper describes a computer-based data sampling and controlling system for UV experiments. The system is composed of chips such as 8031, 8279, 8255, ADC0809, 2764, and 6264, a thermosensitive electric resistor, and sensors for UV and global radiation. This system works automatically to observe temperature, UV radiation, and global radiation, to turn on/off the supplementary UV lamps, and to print out results of measurements.

Abstract:In this paper, wavelet analysis was applied to the study of wind and temperature field in the Boundary-layer, which showed great advantages in the study of the PBL.Wavelet analysis method is a compensation to spectral analysis and multi-scale analysis,but it is superior to them when applied to the study of sudden changes of physical variables.

Abstract:In this paper, based on analysis of climatic regular pattern, a monitoring and assessing system for agrometeorological disasters was established at province level with the aid of satellite remote sensing and geographic information system (GIS). Structure and main function of the system were defined according to principle of structured design, user’s requirement and its main target. With ARC/INFO as supporting software, all built for Anhui Province were basic data bases of drought, flood and waterlogging, and low temperature and chilling injury, models of monitoring and assessing for the disasters, and a service subsystem for response and decision to emergency.

Abstract:There were 111 forest fires in varying degrees during the period from 1987 to 1993 in Lianyungang city. The genesis of the hazard was investigated and corresponding weather was analyzed. Some irrational parts were pointed out of the old rating method for the forest fire weather for the whole country. By introducing effective rainfall and snow depth as impacting factors, a new rating method for forest fire weather was presented, its accuracy being 9% higher than the old one according to forecast verification against forty five forest fires taking place from 1994 to 1996.

Abstract:A meteorological sounding system, consisting of a miniature robot plane, an air-craft-borne digital sonde unit, and a ground-based subsystem. The flight of mini aircraft is controlled by an onboard auto-control system according to a pre-designed navigation line under the guidance of Global Position System (GPS) data. Flight tracking and air sounding data can be transmitted in real time to ground receiver. The ground-based subsystem would process the received data with a computer and display the geographic position and height of the aircraft and meteorological parameters observed. The ground based subsystem can also send command to the aircraft to manipulate its flight in a remote-control manner. The sonde unit measures temperature, pressure and humidity. Wind speed and direction are derived from GPS data.

Abstract:According to the contravariance and covariance characteristics of physical tensors, the author has made a uniform regulation on the physical meaning of subscript and superscript in the expression of a tensor. Thus, a clear display of tensor matrix is given, the operational rule of matrix is made completely suitable for tensor calculus, and a reliable mathematic base is provided for quantitative analysis of the physical tensor.

Abstract:According to the concept of optimum space-matching between ground rainfall intensity,I, and radar reflectivity factor,Z, for a certain Z-H relationship, the paper suggests a new method for quantitative radar observation of precipitation. The height at which radar observations of I based on the given Z-H relationship are most close to the collocated raingauge measurements is determined and, then, precipitation retrieval from radar data is based on the radar observations of I at this height. By means of multi-variable regression and stepwise regression analyses, a number of models are obtained for precipitation estimation with not only satellite IR imagery information such as cloud top temperature and its gradient but also satellite VIS imagery information. It has been found that precipitation depends on lots of factors of which cloud top temperature, albedo, and temporal gradient of cloud top temperature are most significant. It is concluded that models with more variables would result in better estimation of precipitation.

Abstract:In this paper northern hemispheric low-latitude wind and 500 hPa height anomalies in the summer (July) of El Nino/La Nina year and next year are analyzed using the data from 1950 to 1988, and it is found that there are the strongest wind anomalies over the tropical central-western Pacific and which are closely related with the cross-equatorial flow.Different patterns of 500 hPa height anomaly are also found for El Nino/La Nina year and next year.

Abstract:This paper studies the response of the coastal temperature over Jiangsu(JS) to the warming over the Northern Hemisphere(NH) during recent 35 years using two methods, i.e. the principal component analysis and regression estimate. According to the condition of mean warming over the NH, the possible warming amplitudes and their dependabilities over the JS region are estimated for the future climate. The results are as follows: (1) responses for the trend of summer temperature and inter annual fluctuation to the warming over the NH have great uncertainty; (2) except summer the changes of other season and annual mean temperatures are significant in response to the NH warming with winter being most sensitive, and under the NH warming of 1℃, the seasonal warming over the JS region may generally reaches 0.7～0.8℃ with the largest being 0.9℃ in winter; And (3) sensitive and dependable areas are located in Xu Huai Yian areas and the coastal belt respectively.

Abstract:A soil-temperature control system for greenhouse is composed of chips 8031, 8279, 8255, ADC0809, 2864 and 6264. Upper and lower temperature limits are inputted through keyboard and soil temperatures are sampled by ADC0809 with real-time display. The system would alarm and process it automatically while the temperature is overrunning the set limits.

Abstract:Computed results of plume rise height from three plume models are compared with observations and the effects of ambient turbulence on plume rise in the neutrally stratified atmosphere are analyzed. It shows that the ambient turbulence acts continuously on every stage of plume rise. The plume rise height is related to ambient turbulence. The greater the turbulence intensity, the lower the rise height.

Abstract:A remote-control system for switching multi-channel signals input to a multimedia projector is introduced. The components and working principles of the system and its applications are discussed.

Abstract:The optimization to the structure of a wavelet neural network can be implemented if the genetic algorithm is used to determine both the number of elements in input level and that in hidden level while the gradient method is used to compute weighting, stretching and displacing coefficients.