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Rainfall seasonality in Serbia is examined trough the analysis of several indices: seasonality index (SI), individual seasonality index ( SI i) , and replicability index (RI). Based on data from 14 synoptic stations that are well distributed over Serbian territory, spatial distribution of general seasonality index SI ¯ , mean individual seasonality index SI ind ¯ , and RI are analyzed in two subperiods (1961–1990 and 1991–2020). The modified Mann–Kendall test (MMK) and Sen's slope methods are used to investigate the possible trends and its magnitudes in time series of SI i . The values of SI ¯ show that precipitation regime in Serbia is very equitable or equitable with definite wetter season. For the entire Serbian territory, the values of RI are low, indicating that the month of maximum rainfall occurs over large spread of months along the studied periods. The existence of significant negative correlation between RI and longitude is found. Results show a highest influence of the North Atlantic Oscillation and East Atlantic/West Russia pattern on rainfall seasonality in Serbia. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to analyze the rainfall regimes of Pernambuco, a northeastern Brazilian state, based on the seasonality indices (the individual, SI i , and the general, SI ¯ ) and the replicability index, RI . These indices were derived from monthly rainfall data, recorded between 1953 and 2012, at 125 weather stations. The modified Mann–Kendall test and Sen's slope estimator were applied to investigate trends in the SI i time series. A regression analysis of SI i ¯ , SI ¯ , and RI with the geographical longitude produced a statistically significant linear correlation. The calculated SI ¯ index indicates that the mean rainfall regime of the coastal area (Zona da Mata) and the central area (Agreste) of the state can be classified as rather seasonal with a short drier season. The western part (Sertão), in turn, exhibited mean rainfall regime between seasonal and markedly seasonal with a long drier season. Concerning the replicability index, results suggest that Agreste is the region with the least replicable rainfall regime in the state. The analysis of the two 30-year sub-periods shows significant changes in the mean values of SI i indicating the shift in rainfall regime toward extreme seasonality with prolonged dry season in the Sertão region and toward more regular with shorter dry periods in Zona da Mata and Agreste region. [ABSTRACT FROM AUTHOR]