Analysis of phase coherence in fully developed atmospheric turbulence: Amazon forest canopy

Abstract. In a recent paper (Koga et al., 2007) it was shown that the intermittent nature of solar wind turbulence can be characterized by kurtosis and phase coherence index. In this paper, we apply these two nonlinear time series techniques to characterize the intermittent nature of atmospheric turbulence above and within the Amazon forest canopy using the day-time data of temperature and vertical wind velocity measured by a micrometeorological tower at two different heights. By applying kurtosis and phase coherence index to quantify the degree of phase coherence, we identify an enhanced scalar-velocity similarity for in-canopy turbulence compared to the above-canopy turbulence, during the interval of data analysis.