Investigation of the meteorological and hydrological drought characteristics in Yeşilirmak basin, Türkiye

Abstract

This research has examined meteorological and hydrological droughts, considering the need for comprehensive studies on drought and its significant damage. This research considers monthly rainfall data from 16 meteorological stations and monthly streamflow data from 12 hydrological gauging stations. This paper aims to conduct a thorough examination of meteorological and hydrological droughts utilizing the standardized precipitation index (SPI) and the standardized streamflow index (SDI) over timescales of 1 (monthly), 3 (seasonal), and 12 (annual) months in the Ye & scedil;il & imath;rmak basin, T & uuml;rkiye. The Mann-Kendall (MK) and Spearman Rho (SRHO) are employed at all stations to identify monthly trends, respectively. In addition, Wavelet Transform Coherence (WTC) are performed internal connections between the meteorological and hydrological drought in the basin. Trend test results indicate significant drought trends at 1- and 3-month timescales, while no significant trend is observed at the 12-month timescale. The investigation focuses on understanding the connections between drought conditions observed at hydrological and meteorological stations. The trends are more clearly visible when analyzing data over a 1-month period, compared to analyses covering 3-month or 12-month periods. The SPI and SDI indices show the strongest correlation in the northern part of the basin, while the weakest correlation is observed in the eastern region.