基于传递熵方法,分析Lorenz系统x,y,z三个分量之间的信息传输方向,并应用温差与垂直速度的再分析资料对Walker环流进行分析.研究结果表明:1)对于Lorenz系统而言,x与y分量之间,y是信息源,x是信息汇;y与z之间,y是信息源,z是信息汇;x与z分量之间的信息传递方向依赖于控制参数r;且净信息传输的方向不随初值不同而改变;2)在西太平洋地区,温差对垂直速度的净信息输送占主导地位,而赤道东太平洋地区则为垂直速度对温差的净信息输送占主导地位,这与Walker环流物理机制是一致的,且海陆热力差异对温差与垂直速度之间的信息输送影响较大;3)冬季是温差与垂直速度之间的信息输送最强季节,夏季和秋季次之,春季最弱,这可能是存在春季预报障碍的原因之一.以上结果表明,传递熵在气象领域有广阔的应用前景,是测量动力学系统信息传递方向的一种有效方法和工具.
By the transfer entropy method, in this article we analyze the transfer of information between x, y, z component of Lorenz system and Walker circulation with temperature difference and vertical velocity. It is found that y is the information source and x is the information sink between x and y component of Lorenz system, also y is the information source and z is the information sink between x and z component. But the direction of information transfer depends on the control parameter r between x and z component, even if the direction of information transfer between x, y and z component of Lorenz system does not vary when the initial value changes. In western Pacific, the information transfers from the temperature difference to the vertical velocity, while the information transfers from the vertical velocity to the temperature difference in the eastern equatorial Pacific, which is consistent with the physical mechanism of Walker circulation. And land-sea thermal plays an important role in the information transfer between temperature difference and vertical velocity. In winter, the information transfer between temperature difference and vertical velocity is strongest, in summer and autumn it is weaker, and in spring it is weakest, which may be the reasons of spring predictability barrier. These results suggest that transfer entropy is proved to be an effective method and tool of measuring the transfer direction of the kinetic system information, and has broad application prospects in the field of meteorology.