Li Qinglei, Fu Zuntao
Lab for Climate and Ocean-Atmosphere Studies, Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing 100871, China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Jan;89(1):012905. doi: 10.1103/PhysRevE.89.012905. Epub 2014 Jan 6.
How the nonstationarity in the atmosphere turbulent vertical velocity series affects its organization degree of multiscale structures is quantified by permutation entropy (PE) and complexity-entropy causality plane (CECP), and marked PE and CECP differences are detected between the nonstationary and stationary series. We find that the value of PE is lower in the nonstationary vertical velocity series than the stationary counterparts. Both types of series locate near the region of the higher complexity value in the CECP as chaotic systems, but the PE is smaller and the complexity degree is larger in the nonstationary series than the stationary with smaller time delays. Due to the close relationship between PE and the multiscale Shannon entropy, we show that the PE and CECP can be also taken as an indicator to quantify the different organization degrees of the multiscale structures existing between the stationary and nonstationary surface vertical velocity records.
通过排列熵（PE）和复杂度 - 熵因果平面（CECP）量化了大气湍流垂直速度序列中的非平稳性如何影响其多尺度结构的组织程度，并且在非平稳序列和平稳序列之间检测到了显著的PE和CECP差异。我们发现，非平稳垂直速度序列中的PE值低于平稳序列。作为混沌系统，这两种类型的序列都位于CECP中复杂度值较高的区域附近，但在较小时间延迟下，非平稳序列的PE较小且复杂度程度比平稳序列更大。由于PE与多尺度香农熵之间的密切关系，我们表明PE和CECP也可以作为一种指标，用于量化平稳和非平稳地面垂直速度记录之间存在的多尺度结构的不同组织程度。
