Predictions in Ungauged Basins: Promise and Progress (Proceedings of symposium S7 held during the Seventh IAHS Scientific Assembly at Foz do Iguaçu, Brazil, April 2005). IAHS Publ. 303, 2006, 431-440.

 

Application of the wavelet transform for analysis of precipitation and runoff time series

 

CELSO AUGUSTO G. SANTOS1 & SANDRA MARIA ARAÚJO IDEIÃO2

1       Department of Civil Engineering, Federal University of Paraíba, 58051-900, João Pessoa-PB, Brazil

celso@ct.ufpb.br

2       PIBIC/CNPQ Scholar, Department of Civil Engineering, Federal University of Paraíba, Brazil

 

Abstract In order to help the hydrological regionalization, the analysis of precipitation and runoff data was done through the wavelet transform. This analysis seeks to help water administration personnel to take decisions on Predictions in Ungauged Basins, providing more details concerning the infor­mation about the precipitation and runoff patterns within a region. Data from rainfall and runoff stations in Piranhas-Açu River basin, located in semiarid northeastern Brazil, were used and the wavelet transforms were applied to these time series in order to determine zones within the region. In spite of the rainfall wavelet power spectra showed to be very similar, the global wavelet spectra of the main frequency components of the stream flow time series revealed different patterns. A total of 12 rainfall and runoff time series were assessed and their global wavelet spectra, together with the band scale-average time series, can be considered useful for determining the hydrological zones within a region.

 

Key words  rainfall data; runoff data; multiscale analysis; wavelet