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• THE STREAMFIELD, HEATING FIELD AND THEIR ANNUAL VERIATIONS OF THE MEAN AIR COLUMN OVER QINGHAI-XIZANG PLATEAU
• Luo Siwei;Lu Shihua;Yu Jie
• 1983 Vol. 2 (2): 1-8. 
• Abstract ( ) PDF (622KB) ( )
• In this paper, the three dimensional streamfield, heating field and their annual veriations of the mean air column over Qinghai-Xizang plateau are computed by using the 10 year mean aerological data in the Plateau and its surroundings. It shows in summer the air currents converge to the Plateau from its neighbourhood below the 200mb surface and are transformed to diverge outwards at the 100mb surface. In winter it is just contrary. The spring and autumn are transitional seasons. There exist the heat sources of the whole air column over the Plateau in March through September and heat sinks in the other months of the year.The sink at the bottom of air column in March still remains and it appears in September again. The effect of evaporation and condensation of water vapor on heating field is evident.It plays the role of heat sink in winter(Nov., Dec., Jan. and Feb.)at the upper layer and heat source in summer(April through Oct.). The most release of latent heat is at 300-400mb. Evaporation and cooling effect exist at 600mb near ground surface in Feb. through July and the condensation and heating effect appears in other months of the year. The air column is quickly heated and transformed from heat sink to source in Feb.through May and it is mainly due to the contribution of sensible heat, because the latent heat is much smaller than the sensible heat.

• THE EFFECT OF QINGHAI-XIZANG PLATEAU ON THE FORMATION OF DRY CLIMATE OVER THE NORTHWEST OF CHINA
• Xu Guochang;Zhang Zhiyin
• 1983 Vol. 2 (2): 9-16. 
• Abstract ( ) PDF (537KB) ( )
• In this paper, using monthly mean upper wind data(1961-1970), we calculate the mean fields of stream,vorticity,divergence and vertical velocity over Qinghai-Xizang and its surrouudings during January, April, July and October. It is found that in the inside of the boundary layer over the north part of the plateau and to the north of its, anticyclonic vorticity, divergence and downdraft are caused and maintained because of the dynamical friction effect over the lateral boundary of the plateau and the surface of the principal part of the plateau and dynamical rounding flow effect to the E of Tian-Shan mountain and the NE of the plateau. We think that the dynamical effect of Qinghai-Xizang plateau has important influence for the formation of dry climate over the NW of China.

• AN ENERGY BALANCE CLIMATE MODEL WITH ATMOS-OCEAN SYSTEMS
• Chen Yingyi
• 1983 Vol. 2 (2): 17-25. 
• Abstract ( ) PDF (495KB) ( )
• On the basis of paper(1),an atmso-ocean coupling model which takes account of the turbulent transport process only in the ocean and of the exchange of heat between atmosphere and ocean was developed. The distribution of temperature of sea surface was recalculated. The sensibility of climate evolution to the change of solar radiation was examined. It was concluded that the results with or without considering ocean are identical.

• STUDIES OF THE QING ZANG PLATEAU SUMMER PRECIPITATION BY THE USE OF SATELLITE CLOUD PICTURE
• Ye Fangde;Zhou Yunhua;Zhou Shuxiu;Shan Fuzhi
• 1983 Vol. 2 (2): 26-35. 
• Abstract ( ) PDF (634KB) ( )
• By use of the daytime visible cloud picture from TIROS-N meteorological satellite, statistics on the cloudiness distribution of high light clouds over the Qing Zang plateau month by month from May to August of 1979 has been made. It is found that there exists a good relationship between precipitation R and appearing frequency of high light clouds P over the Qing Zang plateau region to the west of 95°E. This relation is expressed as R=APα. The linear correlation coefficients are 0.82 for May and greater than 0.98 for June,July, and August. In addition,by making use of the measuring precipitation data from meteorological and hydrographical stations and also by coordinating with the calculated precipitation from the high light clouds observed from the satellite on 2° × 2° grid, the month by month summer precipitation distribution chart over the plateau is then obtained.From it we also find that in early summer, there is a high precipitation axial line and on its north and south sides there are less precipitation zones.

• THE THEORETICAL FREQUENCY DISTRIBUTION OF THE ANNUAL AND MONTHLY PRECIPITATIONS IN SHANXI PROVINCE
• Yang Guanzhu
• 1983 Vol. 2 (2): 36-41. 
• Abstract ( ) PDF (383KB) ( )
• In this paper,a statistic examination on the frequencies of annual and monthly precipitations in Shanxi Province has been made. The result sho-ws8(1)the annual precipitation follows the normal distribution,(2)the monthly precipitation, after having its cubic root be transformed, follows normal distribution for 83% of all the stations,(3)among the monthly precipitations, those at 58% of all the stations follow the γ(Gamma) distribution and(4)in estimating the montlily precipitation frequencies, the adoption of normal distribution model is suggested.

• A METHOD FOR ANALYSIS OF ISOBARIC SURFACE PATTERNS AND SEA-LEVEL PRESSURE FIELD IN PLATEAU AREAS
• Qian Yongfu
• 1983 Vol. 2 (2): 42-49. 
• Abstract ( ) PDF (494KB) ( )
• According to observational study a method for analysis of isobaric surface patterns and sea-level pressure field in mountainous regions is developed in this paper. By using the method and a suitable horizontal grid system the provincial weather services could get the outlines of the weather patterns in plateau areas. The method is also helpful for numerical weather prediction models in providing a better initial data set and improving the accuracy of calculation of pressure gradient force.