Estudo das características atmosféricas na região do Centro de Lançamento de Foguetes de Alcântara (CLA) / Atmospheric characteristics in the region of the Rocket Launching Center of Alcântara (CLA)

AUTOR(ES)
DATA DE PUBLICAÇÃO

1999

RESUMO

A statistical study of the air temperature, relative humity and wind components was undertaken in order to validate the ECMWF reanalysis data using observational rawinsonde data collected at CLA for the period from 1988 to 1993 at 12:00 Z. The meteorological variables are extracted at the levels of 1000, 925, 850, 775, 700, 600, 500, 400, 300, 250, 200, 150, 100, 70, 50 and 30 hPa. The reanalysis was able to capture important points of the vertical profiles of the rawinsondes, mainly the height and the values (air temperature) of the tropopause, and the changes in the wind direction. However the ECMWF reanalysis data showed stronger humidity than the rawinsondes with differences around 50-70 at 400 and 100 hPa levels. The second part of this work accomplished the identification of the passage of the Easterly Wave Disturbances (EWDs) over the Alcântara region, in the period from 1988 to 1997, using the method of signal change of the meridional component of the wind. This methodology was applied to the 850-700, 700-500 and 850-500 hPa in associatin with an increase of the specific humidity. The cases selected of EWDs detection, they were confirmed by independent data of cloud cover and also by the power spectrum of the meridional component of the wind. The analysis of the V detected the EWDs during all over the year, with time interval varying from 3 to 6 days. This method revealed 64 events in the 850-700 hPa layer, 96 in the 700-500 and 100 in the 850-500 hPa layer, where all presented positive anomalies of the specific humidity how much and cloud cover values around 80 o over Alcântata.

ASSUNTO(S)

rawinsondes waves radiossondas reanálises previsão do tempo ondas de leste previsÃo do tempo e clima weather forecasting

ACESSO AO ARTIGO

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