Variability of Turkish precipitation compared to El Nino events

Potential effects of the El Nino-Southern Oscillation (ENSO) warm extreme on the Turkish monthly precipitation totals between 1931 and 1990 were investigated using precipitation data from more than one hundred and eight Turkish meteorological stations. The data were normalized by using the annual total precipitation to minimize the probable topographical effects. A quiet standard annual variation was determined by month-by-month averaging for each annual month of the Neutral years. The anomalies in percent of the Turkish precipitation data were then calculated by subtracting El Nino-year monthly percent precipitation from the corresponding quiet standard value. The obtained anomalies were sorted after the El Nino high ENSO index month and analyzed by superposed epoch method. Distinct effects of high ENSO index months were found so that a large part of the month-to-month variability may be attributed to El Nino event. Spatially coherent and statistically significant precipitation responses to El Nino were shown in some regions of Turkey.