ISSN 1000-0526
CN 11-2282/P
CN 11-2282/P
Volume 21,Issue 6,1995 Table of Contents
1995, 21(6):3-8.
DOI: 10.7519/j.issn.1000-0526.1995.6.001
Abstract:
The concept of short-term climatic monthly rainfall prediction system is presented. It is discussed that the necessity and posslbility of combining climate model and artificial neural network to develop a Climate Prediction Support System. Then,a scheme for system design is geven and the system structure is also discusssed in detail. Finally,some viewpoints about analysis of predicion results and further improvements are proposed.
The concept of short-term climatic monthly rainfall prediction system is presented. It is discussed that the necessity and posslbility of combining climate model and artificial neural network to develop a Climate Prediction Support System. Then,a scheme for system design is geven and the system structure is also discusssed in detail. Finally,some viewpoints about analysis of predicion results and further improvements are proposed.
1995, 21(6):9-12.
DOI: 10.7519/j.issn.1000-0526.1995.6.002
Abstract:
Sen's probability Distribution Function (PDF) of both dependent and independent series have been introduced. The probability features of critical droughts duration of precipitation for ten-day periods and year to year seasonal periods were analysed at 5 stations,on the Huang-HuaiHai plain.
Sen's probability Distribution Function (PDF) of both dependent and independent series have been introduced. The probability features of critical droughts duration of precipitation for ten-day periods and year to year seasonal periods were analysed at 5 stations,on the Huang-HuaiHai plain.
1995, 21(6):13-18.
DOI: 10.7519/j.issn.1000-0526.1995.06.003
Abstract:
By using digital radar echo data of 13 severe convection affecting Beijing region from June to August during 1987-1991,objective movement forecasting of the radar echo is derived for squall lines entirety and piece echo affecting forecasting region of different intensity with the method of tracking echo centroids. The results show that the method of tracking echo centroids has a fairly good capability of linear objective forecasting to radar echo of the severe convection. The effect of the piece echo movement forecasting is better than that of squall lines entirety,but the movement forecasting effect of non-attenuation echo is the best of them. At last real examples are verified.
By using digital radar echo data of 13 severe convection affecting Beijing region from June to August during 1987-1991,objective movement forecasting of the radar echo is derived for squall lines entirety and piece echo affecting forecasting region of different intensity with the method of tracking echo centroids. The results show that the method of tracking echo centroids has a fairly good capability of linear objective forecasting to radar echo of the severe convection. The effect of the piece echo movement forecasting is better than that of squall lines entirety,but the movement forecasting effect of non-attenuation echo is the best of them. At last real examples are verified.
1995, 21(6):19-21.
DOI: 10.7519/j.issn.1000-0526.1995.6.004
Abstract:
Part of the four-dimesional data assimilation in the second generation medium range NMP operational system (NMP T63) in the National Meteorological Center of China is introduced. The preprocessing of observation report,objective analysis with OI method,diabatic normal mode initialization,forecast model,and post-processing are included in the assimilation scheme.
Part of the four-dimesional data assimilation in the second generation medium range NMP operational system (NMP T63) in the National Meteorological Center of China is introduced. The preprocessing of observation report,objective analysis with OI method,diabatic normal mode initialization,forecast model,and post-processing are included in the assimilation scheme.
1995, 21(6):22-23.
DOI: 10.7519/j.issn.1000-0526.1995.6.005
Abstract:
Among various methods of dividing seasons at a place,the one based on local 5 days mean temperature has been found rather conformable with the actual cooling/warming and the agricultural production at the given place. Yet there are still deficits in that method due to certain artificial factors. By using 5 days running mean temperature instead of 5 days mean temperature in the above-mentioned method, its deficits can be eliminated and its advantages retained. Hence the work of dividing seasons can be accomplished more objectively.
Among various methods of dividing seasons at a place,the one based on local 5 days mean temperature has been found rather conformable with the actual cooling/warming and the agricultural production at the given place. Yet there are still deficits in that method due to certain artificial factors. By using 5 days running mean temperature instead of 5 days mean temperature in the above-mentioned method, its deficits can be eliminated and its advantages retained. Hence the work of dividing seasons can be accomplished more objectively.
1995, 21(6):24-28.
DOI: 10.7519/j.issn.1000-0526.1995.06.006
Abstract:
The process of the weather conditions from drought to rain in Shandong Province in June 1994 is summed up. The results show that the key factors for the successful prediction of the important change lies mainly on the understanding and mastering of the effect of the westerly on the change of subtropical high,and the Pacific ocean,the grasping of the feature of circulation which makes the subtropical high turn suddenly to the north-west,and the use of the factors of experience,NWP the objective forecasting method coordinately.
The process of the weather conditions from drought to rain in Shandong Province in June 1994 is summed up. The results show that the key factors for the successful prediction of the important change lies mainly on the understanding and mastering of the effect of the westerly on the change of subtropical high,and the Pacific ocean,the grasping of the feature of circulation which makes the subtropical high turn suddenly to the north-west,and the use of the factors of experience,NWP the objective forecasting method coordinately.
1995, 21(6):29-32.
DOI: 10.7519/j.issn.1000-0526.1995.06.007
Abstract:
The micrometeorological characteristics of wheat, millet,soybean and paddy fields are analyzed utilizing the Bowen ratio-energy balance method. The results show that: 1)Albedo of wheat field decreases with wheat growth, which is 0. 25 at the enlongation stage, 0. 21 at the boot stage,and 0. 13 at the start of the ripening stage,respectively. Albedo of irrigated soybean field is 0.19 slightly lower than that (0.21) of non-irrigated soybean field. Albedo of millet and paddy fields is 0.21 and 0. 19 respectively. 2) Net radiation over the croplands depends mainly on latent heat flux in daytime,and it is mainly supplied by latent heat exchange at night. 3) Net radiation and its ratio to solar radiation increases with growth of crops.
The micrometeorological characteristics of wheat, millet,soybean and paddy fields are analyzed utilizing the Bowen ratio-energy balance method. The results show that: 1)Albedo of wheat field decreases with wheat growth, which is 0. 25 at the enlongation stage, 0. 21 at the boot stage,and 0. 13 at the start of the ripening stage,respectively. Albedo of irrigated soybean field is 0.19 slightly lower than that (0.21) of non-irrigated soybean field. Albedo of millet and paddy fields is 0.21 and 0. 19 respectively. 2) Net radiation over the croplands depends mainly on latent heat flux in daytime,and it is mainly supplied by latent heat exchange at night. 3) Net radiation and its ratio to solar radiation increases with growth of crops.
1995, 21(6):33-38.
DOI: 10.7519/j.issn.1000-0526.1995.6.008
Abstract:
Sixty-four processes of hailfall are observed and types of hailclouds are classified from the data of rawinsonde, radar and hailshooting observation from 1986 to 1990 in Mancheng Prefecture,Hebei Province. Five types of supercells, dot-source hailcloud, propagational hailcloud, multicells and weak hailcells are classified in this area.The statistical analyses on the data of five years shown that the occurrence frequency of multicells and weak halloeds are more than that of the other types. Serious damages are usually caused by the hailcloud of supercells and propagational cells in Mancheng Prefecture.
Sixty-four processes of hailfall are observed and types of hailclouds are classified from the data of rawinsonde, radar and hailshooting observation from 1986 to 1990 in Mancheng Prefecture,Hebei Province. Five types of supercells, dot-source hailcloud, propagational hailcloud, multicells and weak hailcells are classified in this area.The statistical analyses on the data of five years shown that the occurrence frequency of multicells and weak halloeds are more than that of the other types. Serious damages are usually caused by the hailcloud of supercells and propagational cells in Mancheng Prefecture.
1995, 21(6):40-43.
DOI: 10.7519/j.issn.1000-0526.1995.06.010
Abstract:
The types of response to photoperiod and temperature of eleven PGMR lines provided by 863-101m01 of a special subject identified by artificially controlled photoperiods and sowing/transplant under natural conditions in Wuchang in 1991. The photoperiod/temperature factors and their critical indices which affect fertility change of these PGMR were primitively verified. Rusults showed that the fertility change of all the PGMR were controlled by photoperiod and temperature,and the pure PGMR and TGMR materials not exist. Agrometeology basis is provided for seleting and breeding PGMR of ecological adaptability field.
The types of response to photoperiod and temperature of eleven PGMR lines provided by 863-101m01 of a special subject identified by artificially controlled photoperiods and sowing/transplant under natural conditions in Wuchang in 1991. The photoperiod/temperature factors and their critical indices which affect fertility change of these PGMR were primitively verified. Rusults showed that the fertility change of all the PGMR were controlled by photoperiod and temperature,and the pure PGMR and TGMR materials not exist. Agrometeology basis is provided for seleting and breeding PGMR of ecological adaptability field.
1995, 21(6):44-47.
DOI: 10.7519/j.issn.1000-0526.1995.06.011
Abstract:
The relation between the grain yield and surface water resource in Tianjin during 1963-1990 is analysed. Taken the influence of development of society and improvement of agrotechnique into consideration,the tendency equations of grain yield increased with times have been calculated, and the relative yields, after deducting the increase tendency, have been calculated too.The analysis shows that in the year with surface water resource more than 35×109m3,the grain yield decreases,because there is a lot of water logged lowland in Tianjin;in the year with surface water resource less than 35×109m3 and the last year surface water resource more than 20×109m3,the grain yield increases.The relations among rice,wheat,maize and surface' water resource are analysed respectively,and their close relationship are also pointed out.
The relation between the grain yield and surface water resource in Tianjin during 1963-1990 is analysed. Taken the influence of development of society and improvement of agrotechnique into consideration,the tendency equations of grain yield increased with times have been calculated, and the relative yields, after deducting the increase tendency, have been calculated too.The analysis shows that in the year with surface water resource more than 35×109m3,the grain yield decreases,because there is a lot of water logged lowland in Tianjin;in the year with surface water resource less than 35×109m3 and the last year surface water resource more than 20×109m3,the grain yield increases.The relations among rice,wheat,maize and surface' water resource are analysed respectively,and their close relationship are also pointed out.
1995, 21(6):53-56.
DOI: 10.7519/j.issn.1000-0526.1995.6.013
Abstract:
The modification of GMS-5 satellite data,especially the data format of S-VISSR,as well as the application of new infrared and water vapour images are described.
The modification of GMS-5 satellite data,especially the data format of S-VISSR,as well as the application of new infrared and water vapour images are described.
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ISSN:1000-0526 CN:11-2282/P