Searching chaos and coherent structures in the atmospheric turbulence above the Amazon forest

In this work, the possible chaotic nature of the atmospheric turbulence above a densely forested area in the Amazon region is investigated. To this end, we use high- resolution temperature data obtained during a micrometeorological measurement campaign in the Brazilian Amazonia. Estimates of the correlation dimension (D-2=3.50 +/- 0.05) and of the largest Lyapunov exponent (lambda(1)=0.050 +/- 0.002) suggest the existence of chaos in the atmospheric boundary layer. Our findings indicate that this low- dimensional chaotic dynamics is associated with the presence of the coherent structures within the boundary layer right above the canopy top and not with the atmospheric turbulence per se, as previously claimed.