The main objective of this work is to investigate the influence of topography on the generation of gravity waves (OGs) and their consequent implications on gas transport between different parts of the atmosphere, at night, at the ATTO (Amazon Tall Tower Observatory) experimental site, in the municipality of São Sebastião de Uatumã-AM, in the central region of the Amazon. The experimental data was collected at the ATTO site in the Instant tower of 81 m height. To reach the results, we used Morlet's wavelet transform method, image from the GOES-13 satellite in the infrared band, reanalysis from the ECMWF Era-Interim (European Centre for Medium-Range Weather Forecasts) and numerical simulations of the mesoscale model BRAMS (Brazilian Regional Atmospheric Modeling System) version 5.3. Firstly, an occurrence of OG on the night of the 12th to the 13th of November 2015, through the analysis via wavelet transform. Satellite images showed that rain events did not occur on the night in question, which allowed the annulment of the possibility that the OG had a convective origin. The ECMWF Era-Interim reanalysis were then used, and wave signals were also identified in the air temperature, vertical component of the wind and gases such as CO and O3. Two experiments were then simulated in the JULES-CCATT-BRAMS model, one with the real topography of the region (SC) and the other with the removal of the topography (ST). The simulations results showed up that the presence of the topography intensifies the OG action in air temperature oscillations, in the movement of vertical wind components and in air floatage. Furthermore, the wave transported O3 and CO from burn regions to the ATTO site, a fact that is not significantly observed in ST simulation. Lastly, the simulations proved that the topography had a relevant role in the generation and intensification of OG and its actions in scalars transport near the surface.
|
