Primeiras Análises Estatísticas do Experimento ATTO-CLAIRE (IOP-1/2012)

The Amazon Tall Tower Observatory - ATTO began the first Intensive Operation Period - 1 (IOP-1) of the measurement campaigns in February 2012 as part of the ATTO-CLAIRE field experiment (Cooperative Large-Scale Biosphere-Atmosphere Experiment (LBA) in Amazonia Airborne Regional Experiment). Ten two- and threedimensional ultrasonic anemometers were installed on an 80-meter-high tower. The data collected since February 2012 were used to perform quadrant analyses, wavelet analyses, and to determine the wind vertical profile (inflection point). Data were sampled with frequencies of 10 Hz, 4 Hz, and 1 Hz. The measures were analyzed using the EddyCovariance method. The tower has a triangular cross-section area of 0.156 m2. The equipment was positioned at heights of 78 m; 70 m; 62 m; 41 m; 57 m; 50 m; 45 m; 36 m; 30 m, and 23 m. Northeast wind is the most prevalent, and the average height of the vegetation is 45 meters. The results showed a fairly unique characteristic of the wind vertical profile near and below the inflection point, since wind displacement occurred in the opposite direction to the flow produced by the adverse pressure gradient. According to observations, the geometry of the canopy and the terrain had great influence on this aerodynamic effect of wind profile, as well as the formation of coherent structures, such as coils on theforest canopy in the ATTO.