Abstract:Study is undertaken of basic characteristics of summer quasi-stationary circulationsystems(QSCS)and their intramonthly evolutions by use of a zonal coupled(seaair and land-air)model.Results show that at Northern Hemisphere extratropics,the high-and low-levelQSCS’s are all featured by a zonal bi-wave structure,in complete agreement with the landseadistribution over the belt,thereby confirming that the geographic pattern is the underlying causeof the QSCS’s which show temporal variation largely in the first 20 model days,with the area ofstrongest change generrally being the core of the system.

Abstract:Based on ERBE and ISCCP data the annual contrast pattern of absorbed shortwaveradiation(ASWR)in the atmosphereearth system over China is explored in connection withanalysis of its relation to total cloudiness,planetary/surface albedoes,and surface ASWR,It isfound that the winter(summer)ASWR takes a forrn of being higher in value in the south thanin the north(being asymmetric saddle),roughly in an opposite correspondence to the planetaryalbedo distribution. Besides,the atmosphere-earth ASWR is negatively correlated to totalcloudiness,with higher correlation in the eastern part and the correlation in excess of 0.900between the two types of ASWR for all the stations under study,a result that makes it possible,to some extent,to obtain the surface ASWR from the air-earth analog through retrival in aclimatological context.

Abstract:Northern Hemisphere 500 hPa monthly mean geopotential height fields have been used with the tropical part interpolated reasonably,and coefficients of spheric functions therefrom of the hemispheric height fields have been found for January and July over a range of years. On this basis,the spectral structures of these functions for long-term mean 500 hPa height in the two months have been investigated,showing that the structures are marked by low dimension and order,and the major circulation features and seasonal variation of the height can be portrayed in terms of 20 or so spherical function components.

Abstract:The Kur-Qian p-σ incorprated coordinate five layer primitive equation spherical band(70°N+30°S)model is adopted in this study with effects of Ural blocking high introduced thereinas initial and boundary conditions to investigate the high’s influence upon East Asian summermonsoon circ u lation and dryness/wetness over eastern China with the aid of case contrast andcontrol experiments. Results show that the blocking high as an excitation source is responsible fora SE-NW stationary wavetrain with its upper level anticyclonic divergent circulation(a troughbeneath)lying just over the mid to lower reaches of the Changjiang,which reinforces East Asianwesterly jetstream,beneficiaI to disturbance development and produces an additional secondarycirculation meridionally at the jet’s entrance as well, thus strengthening updraft over the EastAsian monscon region.As such, the Ural high and the related wavetrain represent the large-scale key factor and controlling mechanism for excessive rainfall in the Changjiang-Huaihe valley.

Abstract:Numerical simulation is undertaken of the environmental vapor field of Typhoon 7 of1984. ResuLts show that water content in the passage to the right of the storm’s core is critical toprecipitation, as opposed to the regime to the left and the water flux and its divergence of twoonland typhoons are found to be unrelated to rainfall intensity.

Abstract:Diagnosis is performed of the rainstorm from Typhcon 16 of 1992,indicating that the rainfall is generated through high-level pump ing operated with a low-level cyclon ic flowfield,a high-level anticyclonic flowfield, and a deep vapor-saturated layer available,and that the raingush enhancement is attributed to the typhcon moving into the easterly wave system or a vortex or trough in westerlies,thus leading to intensified warTn advection over the rainband and increased pumping at high levels. Eventually, some remarks are given as to the research and prediction in the scope of typhoon rainstorm.

Abstract:An overall probing of fog was made from central area to borders of the city of Chongqing in the winters of 1989 and 1990.By use of 119 fog droplet spectra taken from five severe events for the urban region,a study is performed of fundamental characteristics of thedroplet size distribution,evolution and main contributing factors,with realistic interpretations given to two of the events under consideration.

Abstract:Atmospheric chaotic properties over a linuted area are investigated in terms of the EOF approach. Compared to the phase spacecont inuat ion based on time lag drifting,orihogonality of basic vectors in the space is fully, guaranteed by the EOF technique whichovercomes the problem of the drifting continuation that can be done of singlestation data only;This paper presents the EOF decomposition and computation of 1980～1986 ECMWF dailygridded data of Asian 500hPa height with the atmospheric fractual dimensionality D=6.2,suggesting that the chaotic attractor behind the atmospheric system should have a 7D system,i.e, seven variables to describe the system.

Abstract:A 3D model for predicting lake-land breeze is constructed in a terrain-following coordinate system,wherein the boundary layer and model top height are found by means of aprognostic equation and boundary layer parameterization is allowed for in a more detailed fashion.Computation shows that the model is quite steady in operation and more capable of describing alake-land breeze disturbance system over a complex terrain.

Abstract:Based on 3aixs anemometer measurements and other meteorological data from Chongqing from December 1989 to January 1990,and the wind measurements,temperaturepulsations and other data in a meteorological context from Tinjin over the period July-August 1990,calculation is conducted of momentum flux, heat flux,frictional velocity and characteristictemperature under different meteorological conditions,The results obtained are of higher value tothe understanding of turbulence flux features in the near surface layer in the suburbs of both thecities with meteorology differing.

Abstract:Using the critical temperature and daylength as indices derived from the fertility alteration model of photoperital-sensitive genic male sterile rice(PGMSR)and 1951～1988 data of daily mean temperature and theoretical daylength from 15 representative weather stations on a national basis,analysis is performed of climatological characte-istics of the fertility alteration data and the duration of the fertile and sterile periods of three male sterile lines(7001s,5088s and Annong s一1).This provides a new approach to the ananlysis of climatic basis for fertility alteration of two-lined hybrid rice and a theoretical basis for further application of sterile line crop to planting.

Abstract:On the basis of the equations coupling model for water/hear transfer in cropped soil,improvement is made on the water-uptake-by-root function(WURF),leading to a version that is related only to precipitation,crop development period a nd leaf area index as the affecting factors whereby a new model of soil water prediction is established.Thus,only with conventional meteorological variables,soil temperature,soil hydrological parameters and crop growth stage fed into the model,can prediction be satisfactorily performed of soil water regime in winter wheatfields, with the maximum relative error averaging within 8%.

Abstract:By means of maximum entropy spectrum analysis made is diagnosis of climatic oscillation in local atmospheric refractive indices in Shanghai and Nanjing. Also discussed are the effects of autoregression models with diverse orders on an entropy spectrum,Stable perieds and spectral peaks are investigated in the spectrum with different sample sizes;The result found can be used as a climatic background in forecasting the change of a refractive index in the air.

Abstract:From a discrete time series derivation is done of two derived quantities for principal oscillation pattern analysis,i.e. ,the principal oscillation pattern(POP)and its associated correlation pattern(ACP).A pratical algorithm is presented from the examples of calculating the POP of a tropical Pacific SST anomaly time sequence and of ACP of the relatedarea 850 hPa wind.

Abstract:Using 1987 twicedaily surface wind data at 300,600,900,500,1000,1500, 2000and 3000m above the ground over China,computation and analysis are made for the streamlinefields features,and the distributions are portrayed on an annual,seasonal and monthly basis forthese levels,with a considerable maximum area found in the boundary layer over all the stationsin the network of the country and its altitude,wind direction/speed and frequency presented.

Abstract:In terms of enhanced satellite infrared cloud imagery and hourly rainfall,analysis is implemented of MCC(meso convective complex) over China mainland to reveal the relation ofthe precipitatinn vigor and fallout sector to the brightness temperature,cloud areas of different brightness and the timevarying change rate of the area inside MCC, Results show that rainfallincreases steadily from MCC foimation to preclimax of cloud,with the strongest intensity occuring 1 h or so before the -53℃ cloud reaches its maximum and when the coldest cloud topslze does the same in the central MCC. Vast difference in the rainfall features is found between MCC’s over the Changjiang basin of Central China and South China. In the end, some considerations are presented concerning the rainfall forecasting in the light of MCC cloudevolutinn.

Abstract:On the basis of 3year observation and analysis of physicoc hemical properiies of winter/spring fog in the urban area of Shanghai,investigat ion is understaken of it s physical attributes,microstructure,acidity and chemical compositions and thereby the genesis,development,dispersal and physicochemical structure are clarified,thus providing a physical background for improving the prediction accuracy and artificial dispersal locally.

Abstract:Based on volume scannings from a 714 digitized weather radar set of Shanghai Regional Weather Center,study is undertaken of the rainfall difference at different heights for asingle station and the region,which is calibrated against the ground raingauge record, wherebythe estimating accuracy is obtained. Moreover,the vertical profiles of the reflectivity factor Z for 3 events in that region“re tentatively investigated.

Abstract:Although investigations of characteristic quantities of raindrop microwave radiation have been documented,the subject needs to be further explored. This article proposes astatistical medel for the relations Z-M,M-I and k-M established by analyzing the raindrop sizedistribution in a rainfall event,Compared with some theoretical medels and relevant datasetsreporied, significant results have been achieved and are of useful reference both in theoretical andpractical aspects of weather prediction.

Abstract:A combination of grey GM(1,1) with Markov predictiori medels is advantangeous inforecasting more accurately a sequence of greater stochasticity and fluctuation, The combinedversion, called the grey-Markov prediction model,is employed for investigating a time series ofAletai goat/sheep mortality rate and forecasting the misfort une in the years to follow, thusproviding a scientific basis for the graziery and d isaster pervention/reduction over Aletai ofXinjiang Province.

Abstract:Nonlinear systematic analysis is utilized to investigate 180 winter cyclone tracks inmidlatitude Europe(25～60°N,0～90°E)and as many of summer typhcon paths over thewestern Pacific(10～45°N, 110～170°E). Calculation of the associated function of independent cyclone pairs and structural function of the tracks indicates that the fractual dimension is 2～2.5(1.4～1.9) for the cyclone(typhoon) atrack attractor in the continued phase space and the track autosimilarity as well.It follows that the time scale of e-folding growth rate of initial erroris 2 to 3 days,the same being true of regionalized paths. Further,the track time scaling indicatesno scaling feature and the associated variance spectra decrease following the 2～3 power law with increasing frequency.

Abstract:Usual verification techniques are outlined for categorical,probability and pattern forecasts with seven criteria proposed for the verifications. Accordingly,the applicability of eachof the three metheds is addressed with reference to small-probability events like severe convective weather. Finallv,an optimal scheme is developed for each of the techniques.