Abstract:By using an alternative method the relative errors are examined of sensible heat and latent heat flux computed from the aerodynamic method. The results show that the relative errors of sensible heat and latent heat rapidly increased as u2.0<2.0m·s-1 and-△e<0.5hPa. The employing of this method is limited in the environment of tiny wind and low humidity.

Abstract:16 cases of northeast cold vortex in China have been chosen,including 8 cases of storm rainfall (type A) and 8 cases of weak rainfall(type B). Their composite diagnoses of physical variables were also done. The results show: 1. In general, the storm rainfall events often take place in the developing stage of the cold vortex,and the weak rainfall occurs in its mature phase. 2. The type A maintains close links with the subtropical low-pressure systems,and this feature is not obvious in the type B. 3. The precipitation centers of the type A are situated in the southeast quadrant of the cold vortex. This rainfall area corresponds well with the high-value areas of low--level convergence, high-level divergence,and low level vorticity, moisture convergence and θse-frontogenesis.

Abstract:Based on the theory of dissipation structure,the calculation formula of atmospheric Wet entropy and the conception of relative wet entropy have been presented. The formula of general entropy flow which is easy to be applied in atmosphere has been calculated. Two weather processes of heavy rain and rain gust in Hebei Province were taken, the entropy evolution and its association with the placement of severe convection storm and with the placement of heavy rain of typhoon low have been analysed. The common ground and difference of the two heavy rain events have been presented. The moving law of typhoon low has been recognized.

Abstract:Meteorological public service is an important work of the National Meteorological Centre. Assisted with mancomputer interactive work-stations and applied with comprehensive meteorological information,the foundation of medium range NWP operational system and advanced computer telecommunication system together make the NMC preliminarily come to operational service system. Therefore weather prediction services have been improved,and also tremendous socioeconomic benefits have been achieved. The overall meteorological service benefits have reached 40 times that of the meteorological investment from the state.

Abstract:Bosed on meteorological data in February and March from 1951 to 1990 at the forty-eight stations in South China,climatic features of spring cool damage are discussed in detail and some facts as follows.1 The more southward in South China,the more concentration toward February with respect to occurrence frequencies of spring lOw temperature process with cool damage. Its damage extent becomes heavier with increasing of latitudes and height above sea level.2 The interannual fluctuations of beginning and ending date of spring cool damage are great with a range of 30 days and 50-60 days,respectively.3 The dominating pattern is moist-cool for spring cool damage and it is mixed pattern as well as dry-cool pattern in turn.4 The peak values of pentad frequency of spring cool damage show a quasi-two weeks oscillation. The strong cool damage has quasi-three to four years cycle.

Abstract:The characteristics of four mesoscale convective systems generated in the eastern Sichuan Province are analysed. The first system was merged from three cloud clusters,and then moved forward rapidly.The second one moved backwark. In the early stage of third system,there were many new convective cells generated continuously in the southwest part of system. Therefore, the system was quasi-stationary. The last system presented cellular structure in the early stage, then it merged with cold front and became a part of the cloud system. All of the four mesoscale convective systems were generated under the condition of the southwest vortex with a warm shear,and their environment flow fields were slightly different.

Abstract:The method of cloud classification and rainfall rate calculation are used in areal rainfall estimation of GMS imagery data. The comparison between estimation and observation of a rainfall event in Aug. 4, 1993. South Huabei of China demostrats that this method is accurate in rainfall area detection and significant in rainfall amount estimation.

Abstract:Twenty processes of the Meiyu front with heavy rain over the Changjiang-Huaihe Valley are analysed by using Q divergence. The distribution and characteristics of the Q divergence on the middle and low layers in troposphere in Meiyu front are studied,the space-time relationship between the belt of heavy rain and the main weather system on the middle and low layers in troposphere is also studied. The results show that Q divergence is comparatively reasonable for forecasting of the area of heavy rain on Meiyu front over Changjiang-Huaihe Valley.

Abstract:The data of giant particles of sulfate observed in Guangzhou during August and September 1987 are analyzed. The main results are:1) The average concentration of sulfate ion nuclei and the average salt content with which dried diameters are larger than 2μm are 1.2 per litre in number and 3. 0μg·m-3 respectively, and the special giant nuclei with which dried diameters are larger than 4μm is 0. 6 per litre in number. They are all much lower than the values observed in Yongxing(Xisha islands) in South China Sea.2) The spectrum type of concentration shows a quasiunimodal and exponential lapse rate,in Which the spectrum parameters are very close to that of the Yongxing island. The spectrum of mass shows a gentle distribution in single-logarithm-coordinate. Therefore all the results show that all size particles have contributed to salt content.

Abstract:Through the study of the relationship between the seedings growth of the Larix-gmelini and the meteorological elements (soil-temperature, air temperature et al.), the best seedling-bed highness and the best moderate soil-defreezed depth for the Larix-gmelini plant are found. Therefore a theoretical and scientific basis is developed.

Abstract:The relationship between the manual breeding of the Yangtze Crocodiles and the meteorological conditions are analyzed. Results show that temperature and humidity are the key meteorological factors that effect the survival rate and the growth of the young crocodile. It suggests that meteorological conditions are very important in Yangtze Crocodile breeding.