Abstract:On the basis of the spherical grid-point data from the ECMWF,a preliminary dynamical diagnosis is made of the blocking high whichpersisted over the Urals during October 4-27, 1981.Results show thatlike the decaying eddies on the track of the Atlantic and Pacificstorms at their last stage, the upstream eddies in this case have propertiesof upgradient transfer, and similar eddy forcing processes also exist inthe persistence of the Ural blocking. Furthermore, the orographic forcingof the Urals should not be neglected. In conclusion, the eddy forcingand the orographic effect of the Urals play a concurrent role in thepersistence of the blocking.

Abstract:Based on the empirical orthogonal function(EOF) analysis,the stepwise iterated interpolation method is built up to insert valuesabsent in the observational data. By this method the SST anomalies absentin the 1950-1980 data have been inserted with good results. Finally, thecharacteristic features of this method and its scope of application are discussed.

Abstract:Based on survey data in the Qinghai-Xizang Plateau for theperiods of May-August 1979 and of August 1982-July 1983, inve-stigation is performed of some major features of the surface net radiation(SNR) varying versus the sun’s elevated angle, height above thc MSL,cloudiness, cloud forms and the condition of the underlying surface,with focus on the profile of the SNR and the sign of the winter SNR.The distribution pattern of the radiation as a function of elevation takes the form of parabola under the clear sky obtained from in-situobservations and numerical studies. Besides, discussion is made of thedecisive effect of the winter snow cover on the SNR, arriving at the conclusion that in winter the SNR remains positive in the main partof the Plateau apart from the sources of the Huanghe and Changjiang Rivers that are likely to be marked by negative values.

Abstract:By the extended empirical orthogonal function (EEOF)method the 30 hPa mean monthly height and temperature fields are expanded, yielding the first four eigenvector fields as well as their variance eontributions and structural characteristics. The circulation regimes typical of the eigenvector fields in winter and summer half years are described.At last periodicity analysis is made for time coefficients by the maximum entropy spectrum method and the major periods for the change of the canonical circulation intensity with time are thus revealed.

Abstract:In terms of the improved Kassam-W ageningen method, calcu-lation is made level by level of the effects of light, temperature, water productive potentiality and soil upon the four major grain crops in the province. The geographic distribution of the crop productivity in sixfarming areas is given together with the prediction of the developmentof the productivity for the forty years ahead. Analysis is made of the productive potentiality to meet the needs of the population growth,followed by the presentation of useful measures for the balance between the necessity and production of crops.

Abstract:By using July-September grid data of 1982 and 1983 from the ECMWF, the teleconnection structure and time-variation of 30-50 dayoscillation of the 500 hPa height field in the northern extratropics and tropics are examined. It is found that the distribution of 30-50 dayoscillation is correlated with the centers of convective activities inthe tropics and with the major centers of the pressure system in the extratropics. The correlation centers of the oscillation are distributed between 15-70°N and arranged in the form of a big are with structural characteristics of a wavetrain and prominent annual variability on their propagation track. The zonal propagation of the oscillation centers corre-sponds to that of the oscillation phase of the height field, which is closely correlated with the energy dispersion of the wave train.

Abstract:This paper analyzes the refraction field near the front in asevere convective weather event and its characteristics, indicatingthat the change of the atmospheric refraction index in time and spaceis related to behaviors of air masses, evolution of the front, latitudeand the type of the underlying surface.Using radar to detect both sidesof the front horizontally, we find that there exist not only detection errors but also "the blind area of detection".

Abstract:The B-model and the IAPAS (Institute of Atmospheric Physics, Academic Sinica) limited finemesh model are nested in one way,and three schemes, i. e., the tendency correction scheme, the relaxation method and the radiative lateral boundary condition scheme, are tested.Tests show that the stability for the integration using the first schemeis the best. Several heavy rain occurrences during the Meiyu period of 1986 are studied using the nested fine-mesh model, the forecasting results of which is greatly improved, with the accuracy of the rainfall values increased by more than 20% and the precipitation distribution closer to actual conditions. The nesting technique stabilizes the integration of the fine-mesh model, lessens the reliance on smoothing, and lengthens time validity of precipitation forecasting. The effect of the boundary conditions on the heavy rain system is also examined.

Abstract:By using the U. S.highway air pollution model(HIWAY-2),the NO_x pollution caused by automobile emission along the Nanjing-Li-uhe Highway(Dingjie straight segment) is estimated.The calculated NO_x concentration is compared with that actually measured, resulting in the correction factors of different stability.The NO_x pollution on bothsides of the segment is also investigated.

Abstract:Detailed analysis is performed of the low-level moisturefields for the 1979-1983 Meiyu periods, showing that the moisture passages in various rainbands have striking characteristics, and that the southerly flow continuously provides moisture for the region in the form of short-period pulses aud the low-level water transportation isdominant in the precipitation. The conclusion drawn in this paper isuseful for operational synoptic analysis.

Abstract:In this paper an automatic fire-alarm system is described,which is designed by using the Model-8031 monolithic microcomputer,the hardwares of smoke and temperature sensors and a supporting software programmed in the MCS-51 assembly language. The system candisplay time and temperature in normal times. When necessary, it canshow calendar through artificial intervention. In case of fire, it cansound the alarm soon after fire occurs and record the beginning time of the fire.

Abstract:Periodical oscillations of the horizontal transfer of the atmospheric heat through the "outside walls" of the Qinghai-Xizang Plateau during the Qinghai-Xizang Plateau Meteorological Experimentin the summer of 1979 are analyzed in detail by means of power spectrum. It is found that there are two major oscillation periods,i. e., quasi-two weeks (13.3 days) and quasi-one week (6.7 days). Some physical reasons are presented for the quasi-two-week period of the horizontal heat transfer.

Abstract:Based on satellite infrared cloud pictures and surface rainfallobservational data, the distribution features of autumn precipitation cloud species affecting the arid and semi-arid areas in Northwest china are analyzed, and regression equations are established for estimating thediurnal precipitation in September-November. These equations can beused to estimate daily and monthly precipitation for the areas short ofdata. Results show that when diurnal precipitation is within the range of 1.0-15.0mm, errors will be small, but the opposite is true when itis within the range of 0.1-1.0mm or≥15.0mm. The estimated monthly precipitation values are generally in agreement with the distribution trend of the observational data.

Abstract:Various large-scale teleconnection patterns universally presentin the northern 500 hPa height field are revealed by using a rotated orthogonal factor analysis method. Results indicate that the teleconnection information obtained concerning the meteorological field is more repre-sentative by factor analysis than by the general EOFs or the one-point correlation map method and the teleconnection distribution patternsare consistent with those described in the literature.It has also provedthat the seasonal features of the teleconnection patterns are reflectedin all the seasons of the year, but their intensity and frequency, for example, may vary in different seasons.