Hydrological Drought and Time Series Analysis: A Case Study of the Zarrinehrood Basin

Abstract

Drought is a significant aspect of Iran's climate, affecting both dry and wet regions. This study examines the river flow data from four hydrometric stations in the Zarrinehrood Basin (Dareh-Panbedan (DP), Pol-Anian (PA), Sonateh and Nezamabad) to analyze and forecast hydrological drought in the present and future periods, considering the impact of climate change. Additionally, the study aims to account for and mitigate the dam's effect on one of the studied stations. The analysis of river flow changes at the studied stations indicated a decreasing trend over the study period. To predict the hydrological drought index for the study area, the SDI index was utilized for reference periods of 3, 6, 9, and 12 months, along with climate change predictors derived from the CanESM2 climate model as outlined in the fifth IPCC report. The CARMA model and climate predictors were employed to simulate and forecast river flow for future periods. The results of the CARMA model investigation for simulating river flow in the test phase indicate that the error value at DP station is 4.07, at PA station is 6.46, at Sonateh station is 4.07, and at Nezamabad station is 70.14 cubic meters per second. These findings suggest that the hydrological drought in the studied basin is expected to worsen in the coming years.

Keywords

• bukan dam
• forecasting
• hydrological drought
• multivariate modeling
• sdi index