Abstract:Numerical results of polarization radar electromagnetic scattering and attenuation of homo-and heterogeneous tapered-spheric hailstones are investigated by using the integral equation method with emphasis on the influence of the scales and shapes.

Abstract:Used in this study are monthly mean temperatures at 10 standard levels from surface to 30 hPa, total ozone and 2 800 MHz solar flux over Antarctic 16 stations in 1962～1993 that are treated by a maximum entropy spectrum method with the aim to uncover the linear trend variation in climate and spectral features at all the levels alongside possible causes discussed for January, April, July and October (as mid season months). Evidence shows that stratospheric temperature (total ozone) is becoming lower (smaller) for these months; 100 hPa temperature (total ozone) shows maximum variability in October of -1.8℃ (-14.8%) per 10 years; tropospheric temperature (2 800 MHz solar flux) has a tendency to warm up (enhance) in these months; 500 hPa temperature (solar flux) has the variability of 0.4℃ (22.1×2 800 MHz) per decade in January with the flux displaying salient periods of 3 and 9～10 years for these months; tropospheric 850～500 hPa temperature variation entropy spectrum exhibits corresponding features only in July; no appreciable trend and periods occur to tropopause temperature in the study months; pronounced decrease of ozone in spring and growth of solar flux in summer represent major causes of stratospheric cooling and tropospheric warming; Antarctic ice melting related to the summer tropospheric warming may be a major cause of sea level rise on a global basis.

Abstract:In the light of experimental results on variation in fertility of photo (temperature)-sensitive sterility line of rice proposed are the eigenvalues and a quantifying model for the variation. The theoretical ground of the model has been demonstrated by multi-plot and long-term observations of seven sterility lines and the scheme is presented for appraising the eigenvalues.

Abstract:Developed is a new system for real time processing weather Doppler radar data operating on the PC Model 486. It is responsible for sampling, displaying and storing data, and furnishing users with echo intensity, radial velocity and spectrun width over a range of scanning manners and also values of I, Q and Z of the signals from linear and logarithmic channels. Besides, the system is characterized by variable parameter setting and being menu driven in its real-time operation and users are allowed to make revision of practically all the variable parameters. Therefore, the presented system applies well both to operational observation and to theoretical research.

Abstract:This paper concerns the latitude effect on atmospheric motion produced by variation in earth′s rotation rate, with the correlativity between the scale characteristics of the subtropical high system and the impact degree documented, the influence on space/time patterns of summertime flood/drought in China investigated, and the u-component difference field, deformation of westerly profile and additional circulation pattern over the western Pacific.

Abstract:Effects of nonzonal basic flow on meso disturbance wave ensemble are investigated in terms of an ƒ-plane nonhydrostatic-balance acousticwave filtering model in natural coordinates through WKBJ and energetic schemes. It turns out that the symmetric evolution of the wave packet depends strongly on the matching in structure of the perturbation and background field; as the basic flow is zonal (curved) the development is related to the inhomogeneous distribution of nonthermal wind in the environmental field with the balance of nongradient wind. Further analysis shows that the wave ensemble development is relevant to the curvature vorticity of thermal wind in the background field.

Abstract:On the basis of comparative study on several classes of nested boundary conditions in current use, developed is a universal boundary condition which can be changed into usual ones, depending on assumptions, whereby it is conventient to compare their merits and demerits with the constraints presented when using these resulting conditions.

Abstract:In terms of the recursive similarity scheme proposed by Liu (1995), study was performed of the state jump of SSTA over the Pacific, Atlantic and Indian Ocean on a seasonal basis over the period 1856～1991. Results show that such jump has a quasi-10 year period if the resolution used is appropriate.

Abstract:The ray theory of geometric optics was applied to visually investigate the propagation of quasi stationary waves in time mean basic flow and interpret the zonal nonhomogeneity. It turns out that squared refraction index (SRI) can be expressed as the derivative of the absolute vorticity with respect to the streamefunction for such a flow and the path is closely related to the spatial pattern of the SRI. The ray has a tendency to travel to a region of maximum SRI (SRI 1) and is difficult to propagate when meeting with a region of minimum SRI (SRI 2). And further analysis shows that the ray, when projecting onto SRI 2 nonperpenticularly (vertically), experiences uni branch (multi branch) refraction. Eventually, the 500 hPa SRI pattern was examined in virtue of measurements, indicating that the scheme can well explain the propagation and multi branch refraction of quasi stationary wave in the real atmosphere.

Abstract:According to the physiology/ecology, and records of radiation, temperature and rainfall from 20 stations in different climatic zones, climatic potential productivity of paulownia is estimated together with its spatial pattern. Also, investigation is made of the general situation of the growth in future climate alongside countermeasures, thereby providing a basis for exploiting the ecological system of paulownia forest.

Abstract:In the context of ERBE and ISCCP data, measured and calculated surface net radiation, investigation is performed of the climatic features of atmospheric net radiation (ANR) over China, along with the relations to its components and affecting factors. Results show that a higher linear correlation exists between ANR and atomsphere-absorbed short-wave radiation is available and thereby a general expression for ANR is formulated based on the relations. A significant tendency of ANR decrease versus altitude and weak increase as a function of latitude in summer is found, with uniform variation in winter. Finally, comparison indicates great difference in ANR pattern and magnitude between our findings and literature.

Abstract:An attempt is made to establish three statistical models for vertical distribution of atmospheric refractive index based on the theory and approach with the aid of conventional radiosonde record from the selected 20 stations in China. Results show that Ⅰ) the 4/3 equvalent earth′s radius model yields minimum accuracy and is applicable to within 1 km of the surface; Ⅱ) the modified version gives maximum accuracy; Ⅲ) the exponential model is effective in the lowest 3 km.

Abstract:Based on the characteristic weather/climate in normal years and natural resources for farming over the agricultural development/demonstration area of Jianmin, Jinhu country, northern Jiangsu, a group of models are developed for planning optimized cultivation for a range of weather/climate patterns on a yearly basis with the aid of science of system engineering. Evidence suggests that under the direction of the models, can be guaranteed a steady harvest of food crops in excess of 15,000 tons each year and oil crop yield and net economic benefit could be made to reach maximum as well.

Abstract:By introducing two concepts——first and second believable levels is proposed a new technique of ensemble forecasting that is applicable to all level stations in the country. It was used in 1990～1992 for decision-making of 8 separate prediction methods that was submitted to the Hydrological Office, Yangtze Water Resources Committee.

Abstract:Investigation was conducted of the digitized radar data operating at Hangzhou and 1 h autographic rainfall from related 58 surface and 156 hydrological stations over Zhejiang province in typhoon seasons 1989～1992, deriving the echo vigor Z and rainfall intensity I associated only with typhoons striking the region during the seasons. Forecasts of 0～3h rainfall category were made following the Z-I relation obtained based on coefficients A and b in Z=A·I^b found over a range of domains in conjunction with the migration of echoes.

Abstract:EOF analysis was done of 1951～1994 temperatures from 18 stations relatively uniformly distributed in Yunnan province to investigate the basic features.

Abstract:The mesoscale model MM4 was adopted to investigate the sensitivity of model simulated rainstorm to moisture transport schemes. Five kinds of advection difference analogs were employed to calculate horizontal transport of vapor, followed by numerical experiments done by the model on three rainstorm events, alongside comparison of the model rainfall from different moisture schemes to the measured. Results suggest that MM4- yielded precipitation is highly sensitive to the vapor schemes and simulation from the positive definite high precision Prather scheme is closest to the observed among the five.

Abstract:Presented is the review of the studies on interdecadal variability in climate with major results documented, alongside the outlook of the study.