• SAYRAN A. IBRAHIM College of Engineering, University of Duhok, Region of Kurdistan-Iraq
  • KHAMLEEN A. MAHMOUD College of Engineering, University of Duhok, Region of Kurdistan-Iraq
  • ZAHRAA M. KLARI College of Engineering, University of Duhok, Region of Kurdistan-Iraq
Keywords: Innovative Trend Method; Mann- Kendall (MK); Estimator of Sen’s slope; Trend Analysis; Linear Regression.


This study examines the trends in daily and annual discharge data from the Deralok station in northern Iraq over a 16-year period (2004-2019). To analyze these trends, several statistical methods were employed, including the innovative trend approach, the non-parametric Mann-Kendall test (MK), and Sen's slope estimator. Linear regression was also used to establish relationships between variables. The results of the annual discharge analysis reveal a clear increasing trend. The innovative trend method indicated positive slopes, with a value of B = 12.37, which is greater than 0. This positive trend was further supported by the Mann-Kendall test, where both tau values were positive, measuring 0.574 and 4.6, respectively, for Sen's slope estimator. Additionally, the linear regression analysis demonstrated a positive slope, amounting to 4.306 m³/year, indicating a consistent increase in annual discharge. Furthermore, this positive trend was observed across all months, from January to December. These findings collectively suggest a notable upward trend in discharge over the study period, with statistical evidence supporting the observed increases.




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How to Cite
IBRAHIM, S. A., MAHMOUD, K. A., & KLARI, Z. M. (2023). DAILY AND ANNUAL DAILY TREND ANALYSIS FOR GREATER ZAB RIVER FLOW AT DERALOK STATION. Journal of Duhok University, 26(2), 298-313. https://doi.org/10.26682/csjuod.2023.26.2.28