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1.
Great advances in statistical meteorology have been made in recent years in China.The mainpoints are as follows:Introducing entropy principle into meteorology,entropy meteorology isfounded;Introducing memory function,self-memorization equation of atmospheric motion isderived;The fuzzy reasoning is introduced into meteorology;Using the method of nonlineardynamics in researches of climatology,some forecasting schemes of phase space are proposed;Chebyshev polynomial is generalized at irregular grids and an iterative scheme for forecast of timeseries is proposed:The wavelet transform is used in researches in climatology;Logisticdiscrimination is used in meteorology and quadratic discrimination and stepwise discrimination areinvestigated;The theory on grey system and the multilevel recursion proposed by Chinesescientists are introduced into meteorological forecast.In addition,complex empirical orthogonalfunction,singular value decomposition,projection pursuit,principal oscillation patterns and so onare also introduced.All the above methods have played great roles in operational weatherforecasts.  相似文献   

2.
近年来中国统计气象学的新进展   总被引:17,自引:5,他引:17  
周家斌  黄嘉佑 《气象学报》1997,55(3):297-305
近年来,统计气象学在中国取得了长足的进展。其中主要有:将熵原理用于气象学,从而建立了熵气象学;引进了忆及过去时次资料的记忆函数,导出了大气运动的自忆性方程;将模糊数学引入气象学;将非线性动力学用于气候学研究,提出了一系列相空间预报模式;将车贝雪夫多项式推广到不规则格点,提出了一种新的时间序列预报的迭代算法;应用子波分析方法进行气候学研究;将Logistic判别分析用于气象预报,研究了二次判别及逐步判别等问题;将中国科学家提出的灰色系统理论和多层递阶方法引入气象预报。此外,还引进了复经验正交分解、奇异值分解、投影追踪、主振荡模态分析等较新的统计学方法。这些方法都已在气象业务预报中发挥了作用  相似文献   

3.
我国冬半年局地气温对北半球增暖响应的特征分析   总被引:2,自引:2,他引:2  
采用主分量分析与回归分析相结合的方法,研究北半球气候变化与我国区域气候变化的一些统计学关系。根据北半球平均增暖的条件,推求我国各地气温变化的统计估计模型,借助某些一般大气环流模式数值试验结果,计算并分析了在CO2浓度倍增时,我国各地增温幅度及其置信区间。结果表明:我各区域与北半球平均增暖趋势基本同步、但幅度不一;我国增暖敏感区主要在西北,华北和东北,南方部分地区的增温趋势有较大的不确定性。  相似文献   

4.
1 INTRODUCTION One of the significant features of global climate change over the past century is the increasing of temperature over contemporary times. Ding et al report generally similar warming trends in China as across the Northern Hemisphere[1]. Study…  相似文献   

5.
近10年我国数值天气预报的进展(1980-1989)   总被引:3,自引:0,他引:3  
廖洞贤 《气象学报》1990,48(1):17-25
对近十年来我国的数值天气预报工作进行了回顾和分析。还对这时期前后的工作进行了比较。从中可以看出,我国数值天气预报的进展是巨大的。还估计了我国和世界先进水平之间的差距,并提出了应采取的措施。  相似文献   

6.
EAA相关链与中国汛期降水   总被引:1,自引:0,他引:1  
该文讨论了 EAA 相关链在南、北半球结构,分析了 EAA 相关链与中国汛期旱涝的关系.进而探讨了它们与前期环流以及北太平洋海温的关系.  相似文献   

7.
黄河上游河南县地面大气冰核观测分析   总被引:7,自引:2,他引:7       下载免费PDF全文
用Bigg型混合云室对2001年8月黄河上游青海省河南县的地面大气冰核浓度进行了观测,分析发现(1)青海省河南县冰核浓度低于北京20世纪90年代的测值,但高于大连、西安和兰州(20世纪60年代)等地的测值,同时也高于黄河上游的玛曲(2000年)、西宁(1989年)两地的测值,高温核尤其偏高.(2)降水时大气冰核浓度减少,降水的冲刷可能是其主要原因.(3)当地冰核浓度和气压成正相关.(4)大气冰核浓度受风向的影响,无风时测值较小,偏东风时测值较大,高温核浓度增加明显.  相似文献   

8.
The research indicates that there is a positive correlation between the negative CG flash rate and the area of radarecho with its reflectivity being equal to or greater than 30 dBz in the mesoscale convective system in Beijing area.A max-imum of the positive CG flash rate exists at both the initial and the dissipating stages.The CG flashes are usually locatednear but not within the high reflectivity center.The negative flashes are associated with.the positions of the updraft re-gion,and with the regions of wind convergence and wind shear.Generally,the negative CG flashes are concentrative andthe positive ones are dispersive.  相似文献   

9.
Based on the daily precipitation and temperature data of 97 stations in Southwest China(SW China) from1960 to 2009, a dry-wet index is calculated. The spatiotemporal variation characteristics of dry-wet conditions,precipitation and temperature are studied. Then the abnormal atmospheric circulation characteristics are discussed using reanalysis data. The results show that SW China has exhibited an overall trend of autumnal drought since the late1980 s, and this drought trend became more significant early in the 2000 s, especially in the eastern SW China. Autumnal dry-wet variation in southwestern China showed two major modes: consistent change across the entire region and opposing changes in the eastern and western regions. The spatial distribution of dry-wet anomalies was more significantly affected by precipitation, while temporal variation in dry-wet conditions was more strongly influenced by temperature. The former mode is affected by the anomalies of the precedent SST near the Western Pacific Warm Pool,the Western Pacific Subtropical High, the East Asian Trough and the South Trough. The latter mode is related to the wind anomalies in the eastern SW China and the vertical movement in the western and eastern SW China. These are the main influencing factors for the autumn dry-wet variation in SW China, which are of great significance to the prediction of drought.  相似文献   

10.
河南干旱年地面雨滴谱特征   总被引:25,自引:3,他引:25       下载免费PDF全文
采用PMS公司生产的GBPP-100型地面雨滴谱仪,对河南省唐河地区17次降水过程进行了连续观测,其中层状云降水14次,积云降水3次。17次降水量都很小,5次有降水而无量,8、9月总降水量分别为8.3mm和31.3mm,占常年降水量的15.6%,属特别干旱的季节,该文利用观测获得的13928个样本,分析了干旱年降水的微结构特征。  相似文献   

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