Analysis of temporal and spatial variations of drought over Serbia by investigating the applicability of precipitation-based drought indices

The precipitation-based indices such as the standardized precipitation index (SPI), the standardized anomaly index (SAI), the rainfall anomaly index (RAI), the percent of normal precipitation (PNP), the China Z index (CZI), and the modified China Z index (MCZI) were compared using monthly precipitation data from 28 synoptic stations in Serbia for the period 1946-2019. The MCZI and CZI showed the lowest similarity to the SPI index that was selected as a reference drought index. According to the findings of the present study, the RAI index was proposed as an index that has the most similar performance to the SPI index. Based on the spatial distribution of the RAI values for the year 2000, the whole region except the western part of Serbia can be classified as extremely dry.