Vol.3, NO.1, 1992

Display Method:
An Improved Initialization Temperature Inversion and Its Preliminary Results over China
1992, 3(1): 1-10.
This paper briefly describes the TIGR data set, the 3I processing system and algorithms, and shows the preliminary results compared with the statistical retrievals over China. It is shown that on the average the 3I retrieval is a bit better than the statistical method, especially, for the Plateau area. On the contrary, the statistical method is better than the 3I for the tropical area.
A Case Study on the Activity of Cloud Clusters with Heavy Rain in Meiyu Front
1992, 3(1): 42-50.
During the periods when the summer low-level convergence zone and convective activity in the Tibetan Plateau are interrupted, the daily variable plain-mountain thermal circulation on the east slope of the Plateau causes the development of convectional systems in the slope region. This is one kind of the mechanism that results in generation of meso-αscale convective cloud clusters is Sichuan basin. When these meso-αscale convective cloud clusters entered the complex topographic region in the middle reaches of Changjiang River, the more complicated meso-scale convective organization appeared and alternation of weakening and strengthening occurred. In macroscopic view, sometimes they stagnated and sometimes leaped down stream. When the convective precipitation in Meiyu front cloud zone is activated and strengthened gradually, a cold band and the corresponding thermal front emerged in the lowest layer, and when a strong meso-αscale cloud cluster with heavy rain developed up, a wave train which is composed of three or four meso-αscale clusters with heavy rain formed in the middle and lower reaches of Changjiang River through a quick adjustment process. As some meso-αscale convective cloud clusters, which are initiated in the low-level unstable region in the south side of Meiyu front, came into Meiyu zone, strong meso-αscale cloud cluster may developed up more easily.
The Imbalance Field of the Heavy Rainfall in the Meiyu Front
1992, 3(1): 108-112.
The mesoscale divergence and its change are in good coincidence with the heavy rainfall in the Meiyu front. The orders of the divergence change and the terms related to vertical velocity (ω) and divergence (D) in divergence equation are larger in the region of heavy rainfall than in the region of weak rainfall. The low—level imbalance field (U) and nonhomogeneous field (A) that are calculated using mesoscale data coincide with the region of heavy rainfall. Calculation of these field and divergence change can provide important information for the nowcast of the mesoscale weather phenomena such as heavy rainfall
Ocean-Meteorouting Data-Base and Its Application
1992, 3(1): 120-124.
Ocean-meteorouting data-base is a special data-base providing weather routing service for worldwide ships. This paper presents mainly its structure, function of applied software and applied effectiveness.
The Description of Some Sodar Echo Patterns
1992, 3(1): 11-19.
The sodar echo patterns of sea breeze, strong wind, katabatic wind and fog are described and compared with meteorological data. Caution must be taken when occur some ambiguous patterns, such as the echoes from the bottom of clouds or elevated inversion, fog or katabatic wind.
The Effects of Ambient Wind on Simulating Convective Clouds
1992, 3(1): 20-31.
The two—and three—dimensional versions of a fully elastic numerical cloud model with ice phase microphysics parameterization are used to investigate the evolution and surface precipitation features of convective clouds in unidirectional low—level wind shear fields. The simulations show that, in order to trigger a convection in low level wind shear environment by thermal bubble, a more intensive temperature disturbance is needed, whereas it can be initiated much easier by cold outflow. Low—level shears with certain intensity lead the peak intensity of convections to decrease, but result in a longer lifetime, larger amount of cumulative surface precipitation, and more extended rainfall area with some smaller peak rainfall rate. Although the two—dimensional simulations of convective activities in vertical shear environment have some severe distortions, the evolution features of maximum updraft velocities and total surface precipitation are coincident with the results of the three—dimensional simulations.
The Interaction Between Nocturnal Urban Atmospheric Boundary Layer and Aerosols
1992, 3(1): 32-41.
Combining with the surface heat balance equation, a nonlinear and unsteady two-dimensional numerical model, which is closed by energy method, has been used to study the interaction between nocturnal urban bounday layer and aerosols. The results show that the effect of aerosols are to warm up the low boundary layer and cool down the upper boundary layer at night; aerosols decrease the stability of low boundary layer and increase the stability of upper boundary layer. In addition, aerosols can decrease the intensity of inversion close to ground. In the city polluted normally by aerosols, the influence of aerosols on the intensity of urban heat island isn’t large, but they can increase slightly urban heat island circulation. The feedback effect of nocturnal urban boundary layer on aerosols is to decrease aerosol concentrations in the low boundary layer and increase in the upper. Part of the above conclusions are verified by the observational data on urban heat island in Tianjin city
Synoptic Climatological Characteristics of Explosive Cyclones over North Pacific in Winter
1992, 3(1): 51-60.
Based on analysis of 500 hPa synoptic maps associated with explosive extratropical cyclone activity over northwest Pacific in winter (from Dec. to Feb.) of 1975—1984, five synoptic patterns of extratropical cyclone development have been summarized in this paper, which are: North America High pattern (NAH), East Pacific High pattern (EPH), Mid Pacific High pattern (MPH), Berling Sea Blocking High pattern (BBH) and Pacific Low pattern (PL). The NAH and EPH patterns occur more frequently and last longer than others, and these two patterns cyclones tend to develop. This paper analyses further the tracking tendency of cyclones after their explosive development and concludes that: during the stable period of synoptic pattern, the cyclone tracks after explosive development are also stable, during the adjustment period of synoptic pattern, the cyclone tracks change with the change of long wave system over 500 hPa, while the wavelength decrease
Utilizing Two Qinghai Tree-ring Chronologies to Reconstruct and Analyze Local Historical Precipitation
1992, 3(1): 61-69.
In this paper, the two precisely crossdated tree-ring chronologies established in Qinghai Province in Northwestern China were used. The weights of monthly climatic factors to the growth of ring width were obtained by calculating the response function. From these months which had significant weights, the best reconstructing period was set by calculating correlation coefficients between tree ring indices and various combination of season climatic factors. Then we use stepwise multiple regression method to reconstruct the historical climate. By analyzing the two local recon strutted precipitation series, we discovered that there were obviously wet periods, drought periods and rainfall periodic variation
Investigation on the Relationship Between Temperature Change and Winter Heating in China
1992, 3(1): 70-75.
According to the national standard on the climate conditions of winter heating (mean daily temperature≤5°), the article calculated the number of days with temperature≤5°, negative accumulated temperature and other necessary parameters. It has been found that between negative accumutated temperature and mean January (or annual) temperature there exists a good linear relation with correlation coefficient as high as 0.99. As a result, two heating zones in China are proposed and the impacts of temperature change on the climate conditions of winter heating in China are studied
Optimization of the City Vegetable Supply Based on Climate
1992, 3(1): 76-83.
To vegetable production in field, climate is the major factor causing fluctuations of vegetable supply. A programming model with multi-objectives of balanced supply, maximum economic profit and minimum cultivated land areas based on demand of the market and the yearly climate variation is established. The quantitative influence of the climate as a random factor on the supply is considered. This has further enhanced the predictability and reliability of the programming model. The optimization of vegetable production in Shanghai obtained from simulation could reduce the imbalance between the demand and supply by 12%, cut 3.24 million yuan of government deficit and save 1264×104m2 of cultivated land
Introduction to Direct Solution Method and Its Application to Wave-wave Collisions
1992, 3(1): 84-90.
This paper, taking Schrodinger equation which may indicate the amplitude evolution of some mesoscale system as an example, mainly describes the direct solution method and its application to the interaction of wave-wave collisions
Generalized Clebsch Transformation and the Conservative Theorem of Potential Vorticity and Spirality in the Atmosphere
1992, 3(1): 91-97.
Generalized Clebsch transformation in a rotating atmosphere is derived in this paper with the aid of Lagrange function, then based on this transformation, the conservative theorem of potential vorticity and spirality in the atmosphere is inferred. Moreover, the theorem is further discussed according to the Hamilton principle and significant results are obtained.
Device Driver Design and High Resolution Graphics Display Development in XENIX/386 System
1992, 3(1): 98-107.
This paper through an example deals with the important concepts and software techniques of the device driver designing in the XENIX/386 operating system on microcomputer, and introduces some ideas for development of high resolution color graphics (or images) display. These research results overcome deficiency of the current version of the XENIX/386. In addition, it provides an efficient way for users to develop the XENIX to support new peripheral devices.
Features and Probable Mechanism of the Medium—range Variation of East—Asia Summer Monsoon Circulation System
1992, 3(1): 113-119.
The spectral analysis has shown that every member of the East-Asia summer monsoon system has a feature of quasi-biweekly period oscillation. They are closely correlated with each other and constitute a self-adjusting mechanism, consequently the East-Asia summer monsoon circulation system presents a medium-range variation process
Spectrum Analysis of Ocean-Atmosphere Elements for Yongshu Reef During Summer of 1989
1992, 3(1): 125-128.
In this paper, the power spectrum and cross spectrum are calculated for the Yougshu reef, a marine meteorological observatory, of the Nansha archipelago, with the ocean-atmosphere elements during the summer (from May to August) of 1989. The results show that: (1) in the variation of meteorological elements, there are two low-frequency waves with 30-40 day and 15. 38 day periods, respectively; (2) as to the two low-frequency waves, there is an obvious lag correlation between pressure and wind, also there is clear correlation between low-cloud and wind velocity; (3) the water skin-surface temperature is characterized by quasi-two week oscillation and is correlated to two-cloud evidently. Finally, a discussion is made on the mechanism of synoptic dynamics and the ocean-atmosphere interaction of these correlations.