Abstract:The suggested method is to derive alinear equation for determining the ex pansion coefficients of electrom agnetic scat tering quasi-analytic solut ion by a lay ered spheroidal particle. To overcome the problem of regional nonorthogonality,corresponding spheroidal angular function is series-expanded into the analog for the environment.

Abstract:The physical mechanism for effect for tropical cyclone intensity on its motion is investigated in a nondivergent barot ropic model with no basic flow.The following results are obt ained.(1)The large-scale beta gyres in the weak(s rong)tropical cy clone are weak (strong)and the ventilation flow speed is small(large).Therefore,it stranslation speed is slow (fast).(2)The difference between azimut halphases of large-scale beta gyres in the weak and strong tropical cyclones and the difference between vent ilation flow directions are all smal. Thus,the difference between their translation directions are also sm all.(3)The periods of oscilation in translat ion speed and vacillation in translation direction in the tropical cyclone are close to the active period of small-scale g yres.In t he inside area of tropical cy clone,the tangential w ind of w eak(st rong)tropical cyclone is small(large),the active period of smal-scale gyres is long(short).Theref ore,the frequencies of oscilation in translation speed and vacilation in translation direction in the weak(strong)tropical cyclone are low(high).

Abstract:In the context of ECMWF May-September 1980～1986 series and EOF technique, investigation is performed of the temporal variation in the behaviors of Indian and east Asian monsoon circulations,indicating that the first t hree principal components of the involved elements show not iceable discrepancy in explaining total variance of pert urbation with great difference between the two monsoon areas;signs of time coefficients related to the first two principal components for the seasonal trend are reversed at least one pentad earlier in the Indian than in the other region;dist urbance of meridional wind is less clear than that of the other elements as regards seasonal trend;the temporal coefficients of eigenvect ors for nonseasonal trend differ greatly in phase space traject ories between the regions.

Abstract:Based on 1970～1989 tropical Pacific SSTA investigation is carried out in detail of power spectral features for a range of gridpoints.Results show that the interannual change is marked by quasi-4,2 and 1.3 year periods,and the spatial distribution feat ured by 1)the SST A signatures quasi-symmetric about the equator over the eastern/mid and western Pacific but in a reversed phase with a significant passage of SST A exchange between the western and cent ral/ eastern segments;2)eastern Pacific strong SST A in antiphase with the weak SST A feature in the equatorial SE Pacific,whose propagat ion characteristics manifest the phase conversion in the tropical mid/eastern and western SST A.The mid/western Pacific SST A plays anessential role in the conversion.Investigated is the relat ion between the multi-time scale interannual chang e and ENSO cycle with the results showing that the quasi-4-year variation of tropical SSTA is the basic period of the cycle,and the phases of quasi-2 and 1.3-year scale in relation to that of quasi- 4-year scale period matt ers signif icantly to the genesis and development of 1970/1989 El Niño events during the period.

Abstract:Relation is investigated of Tibetan winter thermal regime to Asian summ er and Australian winter monsoons in the context of Japan GMS-observed T_BB series.Evidence suggests that with winter warm anomaly in the SW Plateau,the subt ropical summer monsoon rainbelt is northward of mean,and convection is suppressed in the south of the Yangtze river and South China and active convection emerges over the marit ime continent,N W and SW Pacific at low lat it udes,suggestive of active summer(winter)monsoon in the tropical w estern Pacific (Indonesia/northern Australia,and developing subsidence in the equat orial western Pacific. These features are maintained from winter to summer,as exemplif ied by the 1985 case.Also, ant icorrelation in the winter thermal conditions is disclosed between the SW and N E parts of the study region on an interannual basis.As a consequence,it is inappropriate to use the regionaly-averaged thermal condition for research purposes.

Abstract:A climatic retrieval method is developed for the surface total radiation patterns over the Qinghai-Tibet an plateau in terms of ISCCP cloud and act inometric data and adopted to investigate the monthly mean flux density for a gridded band with 2.5°×2.5°resolution in 28. 75～41.25°N,31.25～103.75°E and 70 stations,alongside patterns on a monthly basis, thereby further revealing and confirming basic features of the element under study.

Abstract:Through agency of ground-to-30hPa 10-level monthly mean temperature anomaly series from 16 Antarctic stations and with the aid of maximument ropy power spectral technique, study is conducted of the long-term trend and periodicty of the troposphere and lower strat osphere temperature and of the connection between climatic change in the lower strat osphere (troposphere)temperature and total ozone(southern hemisphere 500 hPa circulation).Results show that Ant arctic temperature exhibit spronounced long-term trend and periodicity; appreciable cooling(w arming)occurs in the lower st rat osphere(troposphere),with maximal variation at 100 and 700 hPa,strongest cooling being by far greater than maximum warming rate and air-layer stability tending to decrease;30 and 50 hPa temperatures possess quasi-biennial period and around 100 hPa temperat ure displays not iceable annual cycle;3.5 year period is dominant as the very low frequency variation in the troposphere;tropopause temperat ure shows no pronounced change in the trend and periodicty;the height where max imum ozone layer emerges has its temperature g reat ly reduced,a fact that is associated with the layer subjected to damages in the past 15 years;the polar vort ex in the southern hemisphere troposphere and circum polar flow weakings represent a direct cause of the tropospheric warming over Antarctics.

Abstract:1951～1985 annual,winter and summer mean temperatures of 160 stations over China are REOF-invest igated with the resulting fields spatialy classified,leading to 7 segments for both the yearly and summer temperature compared to 4 for the winter mean,and multivariate regression extension is conducted of principal components for the areas with long-range observations.Evidence suggests greater difference in these mean fields among the different regions for the past 4 decades,indicating a warming trend in much of the country as opposed to Sichuan basin(annual average temperat ure)and mid-lower Chang jiang valleys(summer mean field),It is found that the temperature trend and phase over China agree with those in the Northern Hemisphere,disclosing a high(low)temperature regime around the 1940s(1970s).

Abstract:Based on analysis of potential vorticity(PV)on isentropic surface and cross section before and after the typhoon landing,study is performed of the PV structure and the evolution of the landing storm interacting with midlatit ude weather systems.Evidence suggests that 1)ty phoon-related PV is a deep high PV column with a high center both in the upper and low troposphere;2)mid-level high PV advection growing with height and shears on the isentropic surface can be taken as an index for the falloutarea of the rainstorm inside the storm and on its surroundings;3)midlatit ude system has effect on the typhoon by transporting cold air into the circulation,whereby the typhoon gets decay ed quickly;4)analysis of isentropy and, particularly,its PV,is an important means for diagnosing and predicting typhoon activity and rainstorm falout region.

Abstract:The 10 level limited area fine mesh model is applied to examine numerically a rainstorm event(July 30,1982)in Sanhuajian region at the Yelow valleys and the model is also used to execute numerical simulation with reduced large-scale jets at upper-and low levels,with results showing wel-coupled jets in the rainf all area;that the jets at both levels contribut e differently to the rainf all genesis from region to region,the low jet playing a more important role;synoptic-scale low-level jet interacting with cold air excites the development of subsynoptic energy front and the rainfal occurrence,and subsynoptic disturbance makes synoptic upper-air jet develop through precipitation condensat ion feedback,an example of scale int eraction in the rainstorm.

Abstract:Because of the problem with a neutronscope in measuring shalow-layer soil moisture, an attempt is made to develop an optimal schme for the purposes based on measurements taken out-and indoors.

Abstract:The Box-Cox transform ation is widely used for obtaining an approximate normaly- distributed random variable.In a linear model setting,a responsive dependent variable Y(or transformed Y)is built on a set of independent variables,usually assumed to be measured with no error.This paper investigates the effects of measurement error in independent variables (known as errors-in-variables)on parameter estimate for the transformation.Ignoring such error in independent variables wil cause biased t ransformation parameter estimate ingeneral,a conclusion that is supported by analytical arguments and stochastical simulation.

Abstract:Based on continuation of 1D monthly rainfal series by lagging parameter τ,a 4D time-lagging equation is used to forecast monthly precipitation for 1980～1994,with correlation coef ficient 0.97 with the measured.Further,the selection of parameters for the equation is addressed.

Abstract:Experimental study is undertaken of a limited area model with comparison of nested- grid and inhomogeneous mesh versions,indicating great advant ages of the latter.A simple scheme is developed for conversing uniform into nonuniform mesh,w ith the conversion and experiment performed of the MM 2 model,yielding satisfact ory results.It is suggested that the scheme can be extended to the global circulation model(GCM).

Abstract:Energy relationships were investig ated inside typhoons 8407 and 8116 and between the in-typhoon and external rainfal areas of the latter by using the complete equation of budgets of divergent and rotational wind kinetic energy.Results show that the available potential energy in typhoon is conversed into rotational kinetic energ y(K_R)through divergent count erpart(K_D). When a typhoon transports the energy out ward,K_R is transf orm ed int o K_D in t he rainf all area through the mechanism of vorticity-diverg ence interaction making K_R transf ormed into K_D which,as enhanced,wil trigger convection development leading to rainfall genesis.This may be one of possible mechanisms for rainstorm aplification.

Abstract:This paper concerns the effect of altitude upon the mode and strength of Penman evaporation est imates varying with radiat ion balance,wind and saturation vapor pressure deficit. Follow ing the expansion of vapor pressure by second-order Taylor series,the problem of possible error is investigated that results from the linearized saturation vapor pressure for the expression of Penmanest imates.

Abstract:The oblique mode scheme is used to examine the teleconnection structure of Northern 500hP a height in July,obtaining a group of teleconnection patterns.Compared to the analyses of 100 hPa height and sea-level pressure fields in this month,its convergent speed is slow,the leading teleconnections are weak and their geographical positions differgreatly from those of the others.

Abstract:In the context of incidence principles and method of gray theory,study is performed of long term meteorological disast ers of graziery in Yili region of Xingjiang,with the application in comprehensive estimation discussed and forecasting made.Results show that the presented gray incidence scheme lends it self to simple calculation;the estimation based on the ordered incidence degrees yields good outcome,avoiding draw backs from a single index only.

Abstract:A method is proposed for the long-range trend of a city as a thermal island by means of the variation in components of surface thermal balance with study examples,indicating that it is of usef ulness to cities that meet the conditions.

Abstract:Based on long-term meteorological observations,numerical products and weather patterns with their combinations,researchis execut ed for their correlativity with recorded rainf al,a province-level summer precipitation probability forecasting automatic system is established in terms of combinations of the probability from multiple factors closely related to rainfal occurrence.Fairly good results are achieved in operational practice.

Abstract:In the light of the dependence on meteorology of red cotton bollworms of different breeds,is established a system for predicting the time and amount of the first,second and third breeds in terms of the products on a medium/long range basis.