Trend Stability Assessment for Hydrological Drought in Euphrates Basin (Türkiye) Using TripleWilcoxon Test and Innovative Trend Analysis Methods
Künye
DEMİREL, İbrahim Halil, Erdal KESGİN, Yavuz Selim GÜÇLÜ, R.İlayda TAN & Büşra BAŞARAN. "Trend Stability Assessment for Hydrological Drought in Euphrates Basin (Türkiye) Using TripleWilcoxon Test and Innovative Trend Analysis Methods". Water, 16.19 (2024): 1-19.Özet
This study investigates the stability of hydrological drought trends in the Euphrates Basin
from 1960 to 2020 using three-dimensional (3D) graphical representations based on innovative trend
analysis (ITA) and triple Wilcoxon test (WT) methods. Unlike traditional ITA and WT, which are
widely used for trend identification but do not inherently provide trend stability information, this
study employs a novel approach to assess and visualize trend stability. The Triple WT method
divides the data into three equal segments, examining differences without altering the time series.
Drought indices are calculated for 3-month, 6-month, and 12-month time scales using historical
streamflow data from five stations. The research identifies trends and their stabilities across three
distinct periods: 1967–1984, 1985–2002, and 2003–2020. Results show that as the time scale increases,
trend differences between extreme drought conditions diminish. One station consistently exhibits
significantly decreasing trends, while three stations show unstable trends with notable variations in
the standardized streamflow index (SSFI). The use of 3D-ITA and Triple WT effectively captures the
dynamics and stability of drought trends, offering a deeper understanding of hydrological drought
in the Euphrates Basin. These findings provide a reference for future studies on drought trend
mechanisms in various climatic regions.