HYDROLOGICAL SCIENCES JOURNAL, 2025 (SCI-Expanded)
In recent years, there has been growing concern in Turkiye and around the globe regarding predicting, monitoring, and preventing drought. This phenomenon is challenging to predict and has emerged in conjunction with deviations from the average in hydro-meteorological data due to climate change. The aim of this study was to investigate drought and changes in drought characteristics of 11 meteorological stations in the Sakarya basin, T & uuml;rkiye. In the study, firstly, change point detection for precipitation and temperature data were determined by Pettitt test. Drought assessment for 1-, 3-, and 12-month time scales was conducted utilizing the Standardized Precipitation Evapotranspiration Index (SPEI), with the objective of calculating drought characteristics. The change in monthly drought index values was analysed using both classical and innovative methods, namely Mann-Kendall (MK), innovative polygon trend analysis (IPTA), and innovative trend analysis (ITA). IPTA test was used to calculate monthly drought index variations and compared with other tests.