Kızılırmak havzasındaki meteorolojik kuraklıkların analizi

Drought, a major phenomenon that has an impact on water resources, viability, sustainability, and the economy, has been one of the most important hydrological concerns. In the literature, it has been classified into 4 groups that are meteorological, agricultural, hydrological and socio-economic. Meteorological drought expresses the precipitation deficits when they are significantly below those recorded normal times. In this study, using Standard Precipitation Index (SPI) and mean monthly precipitation records of 17 stations, a drought monitoring analysis have been done for Kızılırmak Basin, Türkiye, for the time scales of 1, 3, 6, 9, 12, 24-month considering the categories of Severe and Extreme Drought, SED (SPI ≤-1.5) and Severe and Extreme Wet, SEW (SPI ≥1.5). To detect the possible trends in the two categories of all time scales, a developed form of Innovative Trend Analysis (ITA) is performed by adding 2 vertical lines. Also, a traditional Mann-Kendall Test is applied to SPI series. Results have put forth that in all time scales generally dry frequencies are observed as higher than wet frequencies. In addition, mild drought (MD) has higher occurrence percentage than all other drought classes. ITA results have shown that the majority of results for all time scale has shown a trend (89%), the percentage of increasing trend in SEW class is noted as 62.74% and the percentage of decreasing trend in SED class has become 60.78%. Mann-Kendall analysis has shown that the percentages of increasing and decreasing trends in all time scales have been noted as 33% and 67% respectively.