EL NIÑO-SOUTHERN OSCILLATION INFLUENCE ON THE PRECIPITATION IN MARINGÁ-PR, BETWEEN 1980 AND 2016

Abstract

The El Niño-Southern Oscillation (ENSO) affects the climate from different regions of the world which the Southern Brazil is an example. So, it was aimed to understand the ENSO influence on precipitation anomalies in the municipality of Maringá-PR, placed in Central North region of the Paraná State. By using monthly data series of precipitation, from 1980 to 2016, collected in the Principal Climatological Station of Maringá (PCSM)/INMET, it was calculated the local rainfall anomalies. Were also used the Southern Oscillation Index (SOI) and Sea Surface Temperature (SST) data, provided by the National Oceanic and Atmospheric Administration (NOAA). To understand the relationship between precipitation anomalies and ENSO (described by the SOI), it was applied the Pearson and Kendall correlations. Were applied also median tests between three groups of precipitation anomalies: months under El Niño influence, months under La Niña Influence and months of neutral conditions. Results indicated autumn and spring months as the periods of higher correlation among the variables, and the lag time varied from zero to five months. The statistical tests demonstrated positive values of precipitation anomalies during El Niño months, but it is not possible to conclude the inverse effect, at the same intensity, for La Niña.