基于非线性相似度量方法研究中国季节划分

利用中国气象局1961—2008年752个站点的候平均气温、气压、相对湿度和降水量资料,运用候平均气温划分方法、非线性相似度量方法和季节内离差最优分割方法,对中国的四季进行了划分,并研究了中国四季起始时间的空间分布.用多要素构造了描述气候状态的变量,以气候状态在不同季节间的转折变化为切入点,并与传统季节划分方法进行了对比研究,验证了非线性相似度量方法的可行性,得到了以下研究结果:一是多要素比单一的温度要素更全面贴切地描述气候状态的变化,划分结果更体现出大气环流形势和大气活动中心等的季节变化;二是从气候状态转折角度考虑季节划分是可行的,揭示了季节转换时大气系统的调整和转折变化,体现了大气系统在季节内保持相对平稳的特征,在季节间发生较大的调整的观测事实. 关键词： 季节划分 非线性相似度量方法 季节内离差最优分割法

A non-linear similarity method for season division in China

Using the daily observational data of temperature, pressure, relative humidity and precipitation in 752 stations of China from 1961 to 2008, three methods of division of season, i.e. Zhang’s method, non-linear similarity method and Fisher optimal dissection method are applied to different meteorological elements fields of China. Results indicate that division of season through multi-variables methods is more reasonable than single variable ones, especially in non-linear similarity method and Fisher optimal dissection method. When considering the seasonal climate transition between successive seasons, the results are in good accordance with actual observations. As a result we recommend the non-linear similarity method as a better way of season division.