O EL NIÑO E A LA NIÑA E SUAS INFLUÊNCIAS NO CLIMA DE BOM JESUS PIAUÍ – BRASIL

Knowledge of the seasonal climate regime for a region is of paramount importance, because urban and rural planning actions are impacted in different forms and intensities. In this sense, the objective is to determine the influence of El Nino and La Nina phenomena on precipitation, evapotranspiration, deficiency, water surplus and temperature in Bom Jesus-PI. We used series of meteorological data from the National Institute of Meteorology, with annual temperature and precipitation, the water balance was effected. The dispersion analysis of the mean thermal and rainfall values was used in the evaluation of the sinotic elements in relation to the El Nino/La Nina phenomena, using the evaluations of extreme values and climatic anomalies, characterized as the variation greater than the standard deviation. The performance of El Nino/La Nina is not related to increases and/or reduction of rainfall rates, it should be noted that in the classification system, La Nina has very dry and normal classes, with greater significance. About la Nina, that between 1977 and 2006 the maximum daily rainfall occurred in isolation, with rains higher than the historical average. The most intense episode of El Nino increased the temperature of the Waters of the Pacific Ocean by 2.5 °C in November and December, in the historical series from 1977 to 2006, causing isolated maximum daily precipitations. The climate phenomena El Nino and La Nina do not compromise the climate dynamics causing significant changes in the rainfall regime.