Drought analysis with Standardized Precipitation Evapotranspiration Index (SPEI) in Marmara region, Turkey

Drought is a very scalar phenomenon due to time affected by many parameters (Potop et al. 2012). Drought indices have been proposed by many researchers for the calculation of drought. Examples include Standardized Precipitation Evapotranspiration Index (SPEI; Vicente-Serrano et al. 2010), the Palmer Drought Severity Index (PDSI; Palmer 1965) and the Reconnaissance Drought Index (RDI; Tsakiris and Vangelis 2005) (Potop et al. 2012; Bamimahd and Khalili 2013; Wang et al. 2014; Hou et al. 2017; Stagge et al. 2015). The purpose of all these indices is to detect drought and minimize the risks that may occur. In this study the advantage of SPEI compared to other indices used is that it combines temperature and precipitation with evapotranspiration capacity. SPEI has been used to determine drought in more than one country (van der Schrier et al. 2013). In Turkey from the past and present has been used many drought indices. These are available in SPEI (Onusluel Gul and Kuzucu 2017). However, the SPEI calculation was applied for in Turkey's the Marmara Region for the first time in this study. The aim is to determine the drought disaster by achieving a more accurate result with SPEI and to minimize the risk by planning drought (Alam et al. 2017; Dai 2011