Análise estatística e espectral de dados meteorológicos de superfície
Abstract:
This article discusses the spectral analysis of daily meteorological data, extracted from the Meteorological Center of the University of Rio Grande (FURG). The time series corresponds to temperature, atmospheric pressure, humidity and evaporation, measured at Rio Grande city, from January 1990 to August 1995. The spectral approach was made using the professional version of MATLAB Software, mainly the Signal Processing Toolbox. Initially, tests were made for stationarity, periodicity and normality of the time series. Afterwards, the spectral and cross-spectral estimation was computed as well as the autocorrelation, cross-correlation and coherence spectrum of the data analysed. During processing of the time series the Hanning Window, and the low-pass and high-pass Butterworth filters were used. Despite the low frequency data aquisition (one value per day), the spectral analysis shows satisfactory results.