Current Issue

• THE EFFECTS OF ENVELOPE DEGREES OF TOPOGRAPHY ON THE SIMULATED PROPERTIES OF CLIMATE
• Qian Yongfu;Dong Liang
• 1995 Vol. 14 (2): 129-140. 
• Abstract ( ) PDF (452KB) ( )
• A primitive equation model w ith a zonal domain and a p-σ incorporated vertical coordinate system is used to study the effects of the envelope degrees of topography on the simulated properties of climate.Results show that the topography with a larger envelope degree can improve the simulations to some ex tent, especially in wintertime.It is found that the simulated properties of climate are mainly determined by the coeffects of the land-sea and the topographic distributions, and the envelope degree of topography has the second effect, however it should be taken properly in order to get better simulations, otherwise, it wouldbe harmful.Different envelope degrees of topography can be adopted in different areas.

• THE NUMERICAL SIMULATION OF ARTIFICIALLY TRIGGERING LIGHTNING
• Dong Wansheng;Ge Zhengmo
• 1995 Vol. 14 (2): 141-150. 
• Abstract ( ) PDF (352KB) ( )
• In this paper, a two-dimensional plane symmetric model for the simulation of artificially triggering lightning has been developed.To the special triple elect ric structure of Gansu thunderstorm, the triggering height and the magnitude of surface electric field at which the lightning can be triggered successfully, the triggering range and the development of leader channel were calculated for the various charge distribution of thunderclouds.Why it is difficult to trigger lightning successfully when the surface electric field is negative under Gansu thunderstorms was analyzed too.The artificially triggering lightning for in a dipole clectric structure thundercloud has been also simulated.The results show that the central height of the small positive charge at the lower part of the clouds and its magnitude can affect remarkably triggering range and triggering height.The altitude of the whole clouds has significant influence on the triggering height, but little effect on the triggering range.The results also show that the intensity of the surface electric shielding layer has no influence on the triggering height, but can affect remarkably the value of surface electric field.

• THE RADIATION CONDITION OF ATMOSPHERE POLLUTED OVER LANZHOU IN WINTER OF 1992
• Jiang Hao;Ji Guoliang
• 1995 Vol. 14 (2): 151-156. 
• Abstract ( ) PDF (223KB) ( )
• In this paper, the radiation conditions of city atmosphere polluted in winter are analysed on the basis of the radiation data observed at Lanzhou city during Dec.1992 and some new radiation characteristics are found on the basis of observation data over the city.The results are as follow s :the attenuation of solar direct radiation in atmosphere is strong and obviously stronger under 600 m, the maximum ratio of the latter to the former is 42% and mean ratio is 24 %.The lower atmosphere turbidity is less than that 1980 but the maximum value is greater still.The height of layer that global radiation mainly attenuated is in 200-400m.The shortw ave radiation heating in lower atmosphere is about 3.6 ℃/day.The mean albedo over the city is about 0.14.

• CORRELATIVE ANALYSIS BETWEEN THE FAULT AND HAIL DISASTER
• Zhang Hongfa;Deng Ke;Wang Youcai
• 1995 Vol. 14 (2): 157-164. 
• Abstract ( ) PDF (288KB) ( )
• The fact obtained by observing of artificial suppression hail and statistical disaster information for many years in Dangchang County show that the hailcloud active pathes are in keeping with the fault toward.The fallhail is alway s occurring jumpily along the fault lines, and there is a relationship with the sea level elevation and the surface vegetation.The historical rare local disaster of the heavy rain, the flood, the mud -rock flow and the strong hail all appeared at a place w here two or more faults meet.In this paper, the formation of earth-atmosphere coupling is analysed primarily.

• A STUDY ON THE ANOMALOUS VARIATION OF MONTHLY MEAN TEMPERATURE DURING SUMMER IN CHINA
• Li Dongliang;Wu Hongbao;Zhang Jijia
• 1995 Vol. 14 (2): 165-175. 
• Abstract ( ) PDF (413KB) ( )
• In this paper, the spatial structure and temporal feature of summer (June to Aug.)temperature anomaly are studied during 40 years from 1951 to 1990 in China.The results show that there are mainly six types of summer temperature anomaly in China.They are the middle and lower reaches of the Yangtze River, South China, Northeast China, the Qinghai-Xizang Plateau, Northwest China and North China.The anomalous features of summer temperature over the main climatic areas in China are mirrored by analysing temporal tendency of REOF.The variation tendencies of 40 years are that the middle and lower reaches of the Yangtze River is from warm to cool;South China and Northwest China, from warm to cool to w arm;Northeast China, North China and the Qinghai-Xizang Plateau, from cool to warm.There is a good persistence on the summer mean temperature, but the periodicity isn't obvious.In the short period oscillations of same phase, Northwest China appears prior variation than other areas.

• A PRELIMINARY STUDY ON PERSISTENT CAUSEOF THE TRANSVERSAL SECONDARY CIRCULATION OF MEI-YU FRONT IN JULY 1991
• Wu Baojun;Liu Yuling;Yang Yuekui;Wan Zhenshuan
• 1995 Vol. 14 (2): 176-184. 
• Abstract ( ) PDF (320KB) ( )
• In this paper, the multi-level nonlinear balanced ω-equation, the tendency equation of moist static stability and the equation of vapour-flux divergence are used to study the persistent cause of the transversal secondary circulation of Mei-Yu front in July 1991.The results show that the positive feedback of stable condensation heating play an important part.

• A PRELIMINARY ANALYSIS FOR THE RELATIONSHIP BETWEEN THE ANOMALIES OF SOIL TEMPERATURE AND EITHER OF FLOODS IN THE YANGTSE-HUAI RIVER REACHES AND STRONG DROUGHT IN SOUTH OF YANGTSE RIVER IN SUMMER OF 1991
• Ma Zhuguo
• 1995 Vol. 14 (2): 185-191. 
• Abstract ( ) PDF (272KB) ( )
• By using the soil temperature data in China, we have analysed the characteristics of the departure distribution of seasonal mean soil temperature at the depths of 3.2 m and 1.6 m in the Yangtse-Huai River reaches.The results indicate that the range of floods corresponded to the long-duration of high soil temperature in the same area before the summer of 1991;and that the range of strong drought corresponded to the long-duration of low soil temperature in south of the Yangtse River before the summer of 1991.Meanwhile, the results from historical data indicate the durable anomaly of high soil temperature in early stage corresponded to the much rain in the same area, and the durable anomaly of low soil temperature in early stage corresponded to drought in the same area.

• THE APPLICATION OF ANALYSIS METHOD OF QUASI-GEOSTROPHIC Q-VECTOR TO FORECAST OF NINGXIA SUMMER PRECIPITATION
• Che Xiguo;Liu Qingjun;Shen Yueqin;Lu Yun
• 1995 Vol. 14 (2): 192-197. 
• Abstract ( ) PDF (274KB) ( )
• This paper concisely introduces the quasi-geostrophic Q-vector, divergence of Q-vector, and physical meaning of frontogenetical function of Q-vector, and moreover,diagnoses of Ningxia summer precipitation process were madel through analysis method of Q-vector.The result s show the method can reveal the change of precipitation weather, and provide forecasting information for operational forecast.

• OBJECTIVE CORRECTION OF SYSTEMATICAL ERROR OF NUMERICAL FORECAST PRODUCTS
• He Hao
• 1995 Vol. 14 (2): 198-206. 
• Abstract ( ) PDF (302KB) ( )
• We have found the feature and objective criterion of correction about T ₄₂ systematical error from assessmenting performance of T ₄₂ numerical forecast model.The fields of height ( H) and temperature ( T) were corrected by different time weighting and space smoothing.The w ind fields ( u/ v ) were corrected by dynamical method.The humidity fields were corrected by advection (wind field).It is satisfactory that numerical forecast product s objectively corrected have been checked by root-mean-square error mic-lapse rate and error ratio scheme.

• A METHOD OF GREY TOPOLOGY FOR CLIMATIC FORECAST OF TEMPERATURE AND RAINFALL
• Li Guoping;Liu Dongxun
• 1995 Vol. 14 (2): 207-211. 
• Abstract ( ) PDF (188KB) ( )
• By using grey model method, the climatic forecast models of temperature and rainfall in Sichuan Province were established.The forecast results of temperature by using GM (1,1)is very good, but those of rainfall is not.Furthermore, through the grey topological forecast at different thresholds, the forecast accuracy of rainfall is evidently improved.

• THE RELATIONSHIP BETWEEN THE FINE SCATTERED IRRADIANCE AND THE ATMOSPHERIC TRANSPARENCY OVER ARID REGION IN THE WEST OF CHINA
• Gu Linkang;Wang Yaoqi
• 1995 Vol. 14 (2): 212-214. 
• Abstract ( ) PDF (125KB) ( )
• The fine scattered irradiance D is the function of air mass m and atmospheric transparency x, its general formula is D( m, x)=φ( m)ψ( x).We have established the mathematical formula of φ( m)before, the mathematical formula of ψ( x)will be established in this paper.Using two components of Linke turbidity factor T, i.e.wet turbidity factor W, and the rest turbidity factor R as the characteristics of transparency, the mathematical formula ψ( x)= a + bW ₂ + cR ₂ has been obtained ( W ₂ and R ₂ are the values of W and R when m=2, respectively).The values of empirical constants a, b and c are different with the places.

• THE RESEARCH ON ADJUSTING INHOMOGENEITY TEMPERATURE SERIES
• Song Chaohui;Sun Anjian
• 1995 Vol. 14 (2): 215-220. 
• Abstract ( ) PDF (211KB) ( )
• In this paper, based on one-variate linear regression, successive multivariate linear regression, difference value method and aggregate method, the adjustment tests of temperature series have been carried out by using the data observed at thirty-five stations in twenty-five provinces of China.The results show that the best methed is the successive multivariate linear regression, better one is one-variate linear regression.It is also displayed that fitting errors are concerned with the data used in regression equation.The longer the time of parallel data, the better the result is, but it should be longer than 10 years at least.The higher correlation coefficient, the better the result is.If the fitting errors are not more than 0.3 ℃, then correlation coefficients must be higher than 0.90.

• MONITORING AND ANALYSING OF AEROSOLS AT DIFFERENT HEIGHT IN WINTER OVER CHENGGUAN DISTRICT, LANZHOU
• Xi Xiaoxia;Wang Shihong;Chen Changhe;Wu Wenjuan
• 1995 Vol. 14 (2): 221-225. 
• Abstract ( ) PDF (183KB) ( )
• Distribution of quality concentration of the aerosols in the air at different height in winter was analysed by using the aerosols data monitored in the air over Chengguan District, Lanzhou.The results indicate that the air at 50 m level near the surface is polluted seriously by the aerosols.The multi-pollution sources conditions and the climatic environment are the dominant factors causing pollution.

• THE CORRELATION ANALYSIS BETWEEN TYPHOONS IN THE NORTHWEST PACIFIC AND DESTRUCTIVE EARTHQUAKES IN CHINA
• Wei Zhigang;Liu Xiaodong
• 1995 Vol. 14 (2): 226-231. 
• Abstract ( ) PDF (215KB) ( )
• By analysing the destructive earthquakes (Ms ≥7.0 ) in China and the typhoons in the Northwest (NW)Pacific from 1949 to 1979, it is found that there is a good correlation between the both phenomena.When the typhoons in NW Pacific is strong (weak), the destructive earthquakes in China is less (more)in the same year.From M +1 year to the next M year of the even sunspot periods, the destructive earthquakes in China is active but the typhoons in the NW Pacific is relatively weak.Besides, activity of destructive earthquakes in China and reduction of the NW Pacific typhoons of ten appear together with El Nino events.

• THE RELATIONSHIP BETWEEN PBL' SWIND FIELD OVER CHENGDU AND HARD RAIN OVER SICHUAN BASIN DURING SUMMER HALF YEAR
• Li Yueqing
• 1995 Vol. 14 (2): 232-236. 
• Abstract ( ) PDF (177KB) ( )
• In this paper, the relationship between wind's variation in PBL at five stations and hard rain weather over Sichuan Basin (SB)was analysed.It is obtained that the wind field in PBL over Chengdu varies with obvious regularity, and mean wind mainly exhibit alternately northeast wind with southwest wind at 0, 300, 600, 900 m.This variation of PBL's wind over Chengdu has direct relationship with the specific topography of the eastern edge of Qinghai-Xizang Plateau (QXP).When it is northeast w ind in PBL over Chengdu it will be hard rain in SB and when southw est wind it will be rainless.This kind of dynamic trigger action in PBL, connecting with topography of QXP-SB, is an important cause for the occurrence of hard rain in SB.

• STATISTICAL FORECASTING EXPERIMENTS OF MONTHLY PRECIPITATION BY USING ANALOG PRINCIPLE OF PHASE SPACE
• You Weihong;Yan Huasheng;Wu Congbin
• 1995 Vol. 14 (2): 237-242. 
• Abstract ( ) PDF (210KB) ( )
• In this paper, a phase space analog statistical forecasting model for monthly precipitation has been established by using the time series of monthly precipitation in Kunming from 1901 to 1980.The 12 (1981-1992)years'144 predictions and verifications show that the forecast accuracy of anomaly sign of the model can reach over 60 % and it may reach over 70 % in rainy season (May-Oct.)to a proper phase space dimension m nested and within a certain time scale T of predictability.The skill scores of forecast can reach over 8%in whole year and it may reach over 12% in rainy season.

• TEMPERATURE MEASUREMENT COMPARISON BETWEEN PLATINUM RESISTANCE THERMOMETER AND ULTRA-SONIC ANEMOMETER-THERMOMETER
• Zhang Hongsheng;Chen Jiayi;Zhang Aichen
• 1995 Vol. 14 (2): 243-250. 
• Abstract ( ) PDF (253KB) ( )
• For purpose to compare the differences of the temperature fluctuation between the fine platinum resistance thermometer made by self and the ultra-sonic anemometer-thermometer, the temperature turbulence data collected from the HEIFE (IOP-C)in 1992 have been analyzed in the paper.The results show that :(1)the results of temperature standard deviations and heat flux got ten from two instruments are identical;but due to the distance constant of ultra-sonic anemometer-thermometer is larger ( L=20 cm)than the platinum wire thermometer ( L=4 cm), the standard deviations σ _T of sonic are lower than the result s of the resistance platinum w ire, when the atmospheric stability coefficients increased.(2)The corrected values of the ultra-sonic instrument are much lower than the previous studies, due to the lower atmospheric humidity and height instrument located in our experimental occasion.

• REVIEW OF RECENT DEVELOPMENT OF ELECTRIC FIELD MEASUREMENT IN THE AIR
• Xiao Zhenghua;Zhang Yijun
• 1995 Vol. 14 (2): 251-256. 
• Abstract ( ) PDF (250KB) ( )
• This paper discusses several relatively new measuring instruments of electric field in the air, including rocket-, balloon- and aircraft-borne devices.One of them is field mill and another is based on the principle of corona point.Most of field mills w ere designed by using differential structure, and corona points w ere serial connected with a high resistance for measurement linearization.Measuring electric field in the air is important for the research of electric characteristics of thunderstorms.