Evaluation of drought using standardised precipitation and flow indices and their correlations on an example of Sinjs']jsko polje

Sinjsko field is a karst polje situated in the central part of the Cetina River. It occupies an area of 62 square kilometres and has mostly been ameliorated, thus presenting favourable conditions for agriculture. The standardised precipitation index (SPI) and the standardised streamflow index (551) are used in this paper for drought analysis. Meteorological data for the Sinj station, and hydrological data for the Han and Grab stations, collected in the period from 1981 to 2010, are used. The SPI and 551 values are used to define drought periods characterized by their duration, intensity, and magnitude.