Vol.6, NO.3, 1995

Display Method:
A Simple Coupled Earth-ocean-atmosphere Linear Model and Its Experimental Results
Qian Weihong, Chou Jifan
1995, 6(3): 297-303.
Abstract:
A simple coupled earth-ocean-atmosphere linear model has been built. It includes angular momentum conservative relation between the solid earth and the atmosphere, the effect of frictional force from the earth spin’s variation on atmosphere, wind stress on ocean and SST anomalies leading to redistribution of atmospheric mass. Without the external forcing, the result of the model shows that there is a quasi-biennial oscillation (such as zonal wind, SST and the earth spin’s rate) occurred in every part of the earth system. Accordingly, the quasi-biennial oscillation is an inherent oscillation occurred in the interior of earth system
The Relationship Between the Torrential Rain and Liapunov Unstability Movement
Lin Xingqi, Feng Guangliu
1995, 6(3): 304-310.
Abstract:
Using the concept of the second method of Liapunov stability theory, a Liapunov function δ2 S related to the differential equations of atmospheric disturbance is obtained. Form the symbol of the product of Liapunov functionδ2 S multiplied by its differential , the stability of the system can be determined and the occurrence area and intensity of heavy rain are diagnosed. Using this method the experimental forecast for heavy rain is made from June to August of 1993 in the area of three Gores of China. The results show that the forecast accuracy is 5/8.
Modelling Analysis of Huashan Pine Growth Response to Climate
Yin Xungang, Wu Xiangding
1995, 6(3): 257-264.
Abstract:
By employing the tree-growth model, the relationship between the cell size of tree ring and climate for Huashan pine from the Qinling Mts is studied. The cell sizes of early wood, late wood have been measured and modeled using the climate data for 37 years. The modeled cell sizes of Huashan pine and its evolution coincide greatly with the observed one. Response of the measured cell size chronologies to climate indicate that the growth of Huashan pine is mainly effected by the precipitation of current growing season from April to July and of the prior year. The effect of temperature on cell size is shown only in April with a positive correlation.
A Rotated Principal Component Analysis of the Interannual Variability of Temperature in the Lower Stratosphere
ZhangJijia, Wu Hongbao, Ai Likun
1995, 6(3): 265-272.
Abstract:
The interannual variability of the temperature in the lower stratosphere is studied by a rotated principal component analysis. Four fundamental spatial patterns have been obtained, which represent zonally symmetrical anomalies in middle latitudes and in low latitudes, the warm center anomaly in the Northern Pacific and the cold center anomaly near north pole, respectively, Additionally, temporal evolution of anomalies in middle latitudes is the most monotonous, the sign of anomalies is persistent for the whole winter and the interannual evolution clearly shows the character of QBO.
A Study of Application of HIRS/2 Brightness Temperature to NWP Without Retrieval
Wang Zihou, Wang Zongliao, Zhang Fengying
1995, 6(3): 273-280.
Abstract:
A new method to utilize HIRS/2 (High Resolution Infrared Radiation Sounder Model 2) data in NWP (Numerical Weather Prediction) is given. After the geographical location, calibration and other preprocessing, HIRS/2 brightness temperatures (Tb) data from the polar orbiting satellite and conventional meteorological data are directly applied for building an initial field of NWP by using the optimum interpolation method without any retrieval procedures. Analysis and forecast experiments are carried out based on the limited area model from National meteorological Center of China. The preliminary results show that the forecasts from direct Tb data are better than those from satellite retrieval data.
Verification of Precipitation Forecasts for 1993 from Limited-area Analysis Forecast System
Li Yanxiang
1995, 6(3): 281-288.
Abstract:
Synoptic and statistic methods are employed to verify the precipitation forecasts for 1993 from LAFS. The results show that the forecasts for most main precipitation events are successful; the accuracies of moderate and heavy rain predictions are higher than those of torrential rain ones: the accuracy of precipitation predictions for South China is higher than that over the rest parts of China, unfortunately, and the lowest for Qinghai –Tibet Plateau. It is the defects in LAFS that the area of precipitation forecasts is too large.
A Study of Testing Methods on Inhomogeneity of Temperature Sequences
Song Chaohui, Liu Xiaoning, Li Jiming
1995, 6(3): 289-296.
Abstract:
Based on cumulative-departure, successive t-test and regressive methods, the inhomogeneity tests of temperature sequences for 31 stations in 25 provinces are conducted. It is shown that the three methods are valid for inhomogeneity tests of temperature sequences with the significance level a=0.01. And, the conclusions apply to the whole country
Period and Chaos in Discrete Climate System
Cao Hongxing
1995, 6(3): 311-319.
Abstract:
Based on the zero-dimensional climate model a formula of nonlinear mapping is derived, equilibria and a stability basin of the climate system represented by the formula are studied. A regulating feature of oceanic capacities C in the climate system is revealed by means of mapping iterations. Computation results show that there is a narrow sensitive C’s interval which controls a behaviour of the climate system: if C value is greater than that of the upper limit of the interval, the system will tend to a equilibrium state, i. e. present climate: if C value is less than that of the lower limit of the interval, the system will lose its stability. Within the sensitive interval, periodic and chaotic behaviours are emerged in the system. By doubling the period with increasing C, the way to chaos is depicted.
Sensitivity of Summer Rainstorm in Yangtze and Huaihe River Valley to Large Scale Humidity Fields
ZhaoQigeng, Shen Wenhai, Yuan Kaili
1995, 6(3): 320-326.
Abstract:
Using a global spectral model T42L11 the sensitivity experiments to a rainstorm process during period of June 26~July 1, 1991 are performed. The results show that if the vapour sources from Indian Ocean to the Bay of Bengal (to the west of 100°E) were strong cut down, East Asia monsoon circulation would be weakened, and Meiyu precipitation be reduced; on the contrary, when the moisture sources from West Pacific to the South China Sea (to the east of 100°E) were decreased, East Asia monsoon circulation would be strengthened, and the rainfall belt would move over to North China.
A Study of the Diagnostic and Prognostic Method for Distributive Patterns of Summer Rainfall in Eastern China
Chen Yinsheng, Shi Neng, Liu Haibo
1995, 6(3): 327-332.
Abstract:
Three-group stepwise discriminant analysis has been employed to diagnose and forecast the distributive patterns of summer rainfall in eastern China. The results show that the distributive patterns of summer rainfall in China could be diagnosed by using the summer rainfall for the six different stations. Based on the winter 500 hPa polar vortex area indices and teleconnection patterns intensity indices, three-group discriminant functions are established, in which only 7 predictors are included. The fitting frequency is 38/39 for the 39 years data. The test forecast result of 1991 is correct. It can serve as a valuable objective forecast model to the patterns of summer rainfall in eastern China.
A Study of the Trend of Climatic Change During the Period of Next 50 Years
Wang Shaowu
1995, 6(3): 333-342.
Abstract:
A comparison study was made of the modeling results from a series of models to calculate the climatic impact of greenhouse effect, especially, its impact on the climate of China was studied. Meanwhile, the possible natural climatic change in the next 50 years was also considered, which depends mainly on the long-term changes of solar irradiance and volcanism. It is shown that the cooling associated with the natural climatic variability may compensate to some extent the warming caused by the strong increment of greenhouse effect. However, the greenhouse effect will gradually predominate over the two factors above mentioned after 2010 AD. Global mean temperature may rise over 0.6℃ in the 2030s in comparison with the annual mean of 1961~1990. It is possible that the temperature increment in East Asia will be greater than that averaged for the globe. Annual precipitation will be increased in general over East Asia, but summer drought may be intensified in the northern China with increasing of evaporation and decreasing of rainfall.
A Study of the Effect of Ozone on Crop
Wang Chunyi
1995, 6(3): 343-349.
Abstract:
Ozone is one of the atmospheric trace gases. The increasing of O3 content in ground layer would directly make an impact on the growth of crops. The techniques of studing about the effect of ozone on crops and its experimental results from abroad are briefly introduced, and advances in the influence of ozone on crop in China are also shown.
Preliminary Study of Relationship of Meteorological Elements with Surface Ozone in Remote Area
Ding Guoan, Luo Chao, Tang Jie, Liu Qijun, Fang Xiumei, Wu Fan
1995, 6(3): 350-355.
Abstract:
The relationship between surface ozone and different meteorological elements is analysed. The data is obtained from PRC-USA joint mission for atmospheric chemistry during the period of August ~ November, 1991 in Lin’an background station. The results show that global solar radiation is one of key factors for surface ozone concentration.
The Assessment of Agricultural Drought Condition from Farm Water Requirement
Qi Laifu
1995, 6(3): 356-360.
Abstract:
In this paper, farm water requirement, moisture index and integrated moisture index are computed for every month, season and year by using the data of monthly rainfall and temperature for 160 stations in East China during the period of 1951~1990. And, the profit and loss of farm water requirement and drought condition for seasons in China are analysed.
The Scenario Analysis of Possible Effect of Warming Climate on Rice Growing Period
Cui Duchang
1995, 6(3): 361-365.
Abstract:
Temperature is one of basic factors to influence the growth and development of crops, and decides the length of growing period. The relationships between the length of rice growing period and temperature are analysed by using data of rice ecological experiment. The results show that during rice growing period, when mean temperature rises 1℃, the days of growing period decreases 7.6 days. According to experts’ prediction, air temperature will rise 1~4℃, due to warming climate, which makes the growing period of single cropping rice and early rice in China shorten. The isogram of the date of growing period in the eastern China will remove northwards, 1~5 degrees latitude in Northeast China, 3~6 degrees in the Huang-Huai-Hai Plain. The growing period’s getting shorter can be mitigated by taking following measures: adjusting the planting season, selecting appropriate rice ecological types and regulating temperature with water
The Effect of Greenland Sea Ice Anomaly in June on the Drought-flood in Upper-middle Reaches of Yellow River in July
Hu Zengzhen.
1995, 6(3): 366-372.
Abstract:
By using the relationship between DQ% index of sea ice in 4 regions of Arctic and the precipitation for 160 stations in July over China, the diagnostic study is made. It is pointed out that there is close correlationship between Greenland sea ice anomaly in June and the droughts-floods in upper-middle reaches of Yellow River in July. When Greenland sea ice in June is below (above) normal, the flood (drought) is easily happened in upper-middle reaches of Yellow River in July. The physical mechanism of this correlation is investigated. Based on the significance test of the correlation field, the statistical reliability of the correlation above mentioned is confirmed. It is also found that the correlation between random number series and meteorological element fields sometime can reach high significance level, and that distribution of significance correlation area in the correlation field is not in disorder, but in ordinal area. The article shows that it is necessary to combine the significance test of correlation field with the physical mechanism analysis of causing of it.
A Study of Heavy Rain Signature Recognition by Radar Velocity Images
Zhang Peiyuan, ChenRonglin
1995, 6(3): 373-376.
Abstract:
The spatial structures of heavy rain by Doppler radar velocity images, i. e. “Adverse Wind Regions” (AWR) were studied using Doppler radar observation data. AWRs were analysed by statistical data in Beijing-Tianjin-Hebei mesoscale experiment base during the period of 1989~1992. According to AWR occurrence, the forecasting for torrential rain could be made. Its forecast accuracy and probability were tested by CAMS Doppler radar data in 1993. The accuracy was 75% and the generalization for AWR was 86%.
Inverse Experiment of Atmospheric Water Vapor over Ocean from SSM/I Data
Hu Xiaoxin, Li Guangqing
1995, 6(3): 377-384.
Abstract:
The atmospheric water vapor amount during the rainfall of July, 1987 in Bohai Bay was retrieved from SSM/I data. By comparison with radio sounding and surface observations of precipitation in the same period, the results show that the retrieved water vapor amount is in agreement with radio soundings, and also reflect the special distribution and temporal variation for non-convective precipitation