Current Issue

• PERIODIC AND NONPERIODIC VARIATONS WITHIN THE BAROCLINIC QUASIGEOSTROPHIC CURRENT
• Luo Zhexian
• 1986 Vol. 5 (1): 1-7. 
• Abstract ( ) PDF (413KB) ( )
• By the way of the low-order spectrual model, the two-layer quasige-ostrophic model is transformed into an eighth-order forced, dissipative, and nonlinear system. With the gradual changes of the thermal forced parameters, flow patterns of the baroclinic quasigeostrophic current which are represented by the variations of the distance functions, can change from periodic to aperiodic. The Liapunov's indexes corresponding to six different sets of the Poincare's cross-section charts are all positive value. That is just the character of local aperiodic instability.

• A PSEUDO-SPECTRAL DIAGNOSTIC MODEL Part Ⅰ: Scheme designing
• Yan Hong;Wang Keli;Li Suhua;Chen Yuchun
• 1986 Vol. 5 (1): 8-15. 
• Abstract ( ) PDF (461KB) ( )
• The basic method and numerical schemes of pseudo-spectral diagnostic model is discussed for the global and limited area in this paqer. A numerical scheme of vertical integration of continuity equation is presented here to generalize two common used schemes, i.e. so-called "upward integration" method and "downward integration" method. The method presented in this paper has a high accuracy and a low requirement to the computer. It is also applicable to a global as well as a limited area.

• A PSEUDO-SPECTRAL DIAGNOSTIC MODEL part Ⅱ: Verification Tests with Ideal Flow and Real Odserved Fields
• Yan Hong;Li Suhua;Wang Keli;Chen Yuchun
• 1986 Vol. 5 (1): 16-28. 
• Abstract ( ) PDF (779KB) ( )
• The pseudo-spectral diagnostic model(see details in the Part I) is verified with an idealized analysis flow field as well as the observed data from FGGE Ⅱ data set(ECMRWF) with comparison to the second order and forth order finite difference schemes.The results show that for the meso-scale diagnostics with a given horizontal resolution, the pseudo-spectral method seems to be the best, the forth order finite difference method is better than the second order finite difference scheme which is widely being used in weather analysis. Therefore the pseudo-spectral diagnostic model, with a higher accuracy, is more suitable for the diagnostics of meso-scale system.

• THE INTERACTS OF POLAR VORTEXES AND SUBTROPICAL HIGH OVER THE WEST PACIFIC AND THEIR RELATIONS TO SEA SURFACE TEMPERATURE OVER THE PACI
• Wu Bo
• 1986 Vol. 5 (1): 29-39. 
• Abstract ( ) PDF (760KB) ( )
• This paper have studied the interacts between the subtropical High over the West Pacific(hereafter referred to as SH)and the Polar Vortexes in summer (hereafter referred to as PVs), discussed the influence of previous variation for the one of two systems above on the variation of time lag for the another, and also investigated the thermal influences of both the abnormal transport of sensible heating for winter's Kuroshio current sea surface temperature and the change for Orashio current sea furface temperature on the SH and the PVs. Because the Kuroshio and Orashio currents over the Pacific are the one of cold and heat sources for global atmospheric motion. The results pointed out that both the sea-air thermal effects of winter's Kuroshio current sea surface temperature on the distributions of summer'PVs and the different anomaly distributions between Kuroshio and Orashio currents sea surface temperature corresponded to the different rain patterns in Hebei province in summer.

• A STATISTICAL RELATIONSHIP BETWEEN THE FIELD OF SOIL TEMPERATURE IN WINTER AND OF THE PRECIPITATION IN SPRING AND FLOOD SEASON
• Tang Maocang;Yin Jianhua;Cai Jieping
• 1986 Vol. 5 (1): 40-52. 
• Abstract ( ) PDF (789KB) ( )
• Based upon the Chinese data from 1954-1983(30 years), the anomalous maps of soil temperature at the depth of 0.8m and 1.6m during winter (Dec.-Feb.) and the anomalous percent maps of precipitation during spring (Mar.-May) and flood season (Apr.-Sept.) were analvsed. Contrasting the two sets of maps year by year, we find that the axes of maxima of soil temperature anomalous(T'axes) of 0.8m (1.6m) depth almost lay close to the axes of precipitation maxima(R'axes) of spring(flood) season. The R'axes are always shifted to the north 1-2 ° lat. Contrasting with T'axes, when the West Pacific Subtropic High(WPSH) was strong during the last year and P'axes are shifted to south 1.5-2° lat., when the WPSH was weak.

• THE CHARACTERISTICS OF ICE CRYSTAL CONCENTRATION DISTRIBUTION IN COLD CLOUD
• Liu Wenbao
• 1986 Vol. 5 (1): 53-61. 
• Abstract ( ) PDF (531KB) ( )
• The measurements taken by aircraft Piper-Aztec of France during the experiment of the Precipitation Enhancement Project organized by the WMO in Spain in 1981 have been analysed.The results show that.(1) The ice crystal concentration in cumulus, stratocumulus and nimbostratus can reach to the order of 10 ²-10 ³/litre.The concentration of ice crystal seems nothing to do with the cloud type and whether it has precipitation or not.(2) The maximum concentration of ice crystals in the cloud, no matter whether it contains precipitation, appears always at the region of -3℃-7℃, while in precipitating cloud the other maximum concentration regions (-9℃-12℃ and -16℃-19℃) often occur.(3) Besides ice crystals, graupels and tiny ice needles and a considerable amount of cloud droplets in size of d≤15μm and d≥24μ.m are also observed in the region of -3℃-7℃.It seems that the high concentration of ice cryatal in that region is due to the multiplication of a secondary splinting mechanism.(4) The temperature difference between cloud base and top always reach to or more than 15℃ for cloud with precipitation and less than 15℃ for cloud without precipitation.

• THE COMPOSITIVE ANALYSIS OF BROAD HEAVY RAIN STORMS OVER SICHUAN BASIN Part Ⅱ: The Fields of Temperature, Humidities and Unstable Stratifications
• Yu Shuhua
• 1986 Vol. 5 (1): 62-70. 
• Abstract ( ) PDF (579KB) ( )
• Having discussed the potential height and wind fields, in the Part I of the series papers[1] in part I, we continue to discuss the fields of temperature, humidities and unstable stratifications of 23 cases on the middle and lower levels in the troposphere. The conclusions of the compositive analysis show that each type of heavy rain storms occures respectively in a different basic temperature, humidities environment. According to these analysis and the former analysis, we have drawn some general conclusions that can be applied to forecasting the broad heavy rain storms over Sichuan Basin.