Acessibilidade / Reportar erro

Disaggregation of daily rainfall data for the Caraguatatuba city, in São Paulo State, Brazil

Desagregação de chuvas diárias para a cidade de Caraguatatuba, no estado de São Paulo, Brasil

ABSTRACT

The objective of this study is to present disaggregation coefficients for intense daily rainfalls for E2-046 rainfall station, located at Caraguatatuba, São Paulo state. The data obtained through rain gauge refer to a continuous period (31 years of series) and had a strong correlation with the measurements of the rain gauge, validating the pluviographs reading, which attributed greater reliability to the results. The average coefficient “24 hours”/“1-day” found for the study region was 1.075, which differs significantly from the values found in literature. The relative deviation considering other durations, and consequently other precipitation coefficients in relation to the mean values of the disaggregation values of the E2-046 station reached 22.06% (18 hours/“24 hours”). The relative deviation of rainfall disaggregation coefficients of the station studied in relation to the mean coefficients for the cities of São Paulo State to small durations was quite high, reaching almost 50% (10 minutes /“24 hours”). This reinforces the need of using local disaggregation coefficients.

Keywords:
Disaggregation; Intense rainfall; Rain gauge; Caraguatatuba

Associação Brasileira de Recursos Hídricos Av. Bento Gonçalves, 9500, CEP: 91501-970, Tel: (51) 3493 2233, Fax: (51) 3308 6652 - Porto Alegre - RS - Brazil
E-mail: rbrh@abrh.org.br