Comparison of Rainfall Characteristics at Fortaleza (Ceara) and Other Nearby Locations in Northeast Brazil

摘要

The rainfall series of Fortaleza (Ceara) is compared with similar series for several other locations in Northeast Brazil. It is shown that the correlations are good for distances up to about 600 km from Fortaleza. A Master Curve for 1912-1978, obtained by averaging rainfall data for 93 stations having good correlations with Fortaleza, shows very prominent periodicities at T = 5.6, 12.3, and 47.3 years and less prominent periodicities at T = 3.4 and 4.3 years. Predictions from both the Fortaleza series (1849-1976) and the Master Curve (1912-1978) indicated droughts during 1979-1983. This prediction seems to have been realized. In future, droughts during 1992-1994 and 2002-2006 are indicated.