Borko Stosic

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1 Introduction Various indicators for the detection of drought have been developed. Palmer (1965) proposed the Palmer Drought Severity Index (PDSI); McKee et al. (1993) introduced the Standardised Precipitation Index (SPI); Tsakiris et al. (2007) proposed the Reconnaissance Drought Index (RDI); Vicente-Serrano et al. (2010) proposed the Standardised Precipitation-Evapotranspiration Index (SPEI).

CONFLICT OF INTEREST STATEMENT The authors declare no conflicts of interest. REFERENCES (2017) Climate_indices, an opensource Python library providing reference implementations of commonly used climate indices. Available from: https://github.com/monocongo/climate_indices & (2020) Long-run trend in agricultural yield and climatic factors in Europe. Climatic Change, 159, 385–405.