Evaluation of a Combined Index Based on Hydrological Model for Drought Monitoring in Central Iran

• Published in: Water resources 2024-12, Vol.51 (6), p.1026-1041
• Main Authors: Niazi, Y., Talebi, A., Hassan, M. A.
• Format: Article
• Language: English
• Subjects: Aquatic Pollution; Components; Correlation coefficient; Correlation coefficients; Drought; Drought index; Drought monitoring; Earth and Environmental Science; Earth Sciences; Energy balance; Environmental monitoring; GRACE (experiment); GRACE satellite; Groundwater; Groundwater levels; Hydrogeology; Hydrologic drought; Hydrologic models; Hydrology/Water Resources; Infiltration capacity; Land surface models; Moisture content; Remote monitoring; Remote sensing; Satellite data; Satellite imagery; Satellites; Software; Soil moisture; Soil water storage; Temporal variability; Temporal variations; Waste Water Technology; Water balance; Water Management; Water Pollution Control; Water Resources and the Regime of Water Bodies
• ISSN: 0097-8078; 1608-344X
• DOI: 10.1134/S0097807824600086

In recent years, drought has become a global problem. Undoubtedly, drought monitoring is an important step for combating and reducing the resultant damage. Soil moisture, namely its spatial and temporal variability, is one of the most important environmental variables. Due to the difficulty cost, and timeliness of field measurements, this parameter has not been used widely in drought indexes. The recent development of global databases based on satellite imagery as well as rapid progress in hardware and software for modeling complex processes governing the water balance at the land surface employ these new tools to reduce the limitations in this field. The purpose of this research is to provide a comprehensive drought monitoring approach by integrating remote sensing data and the variable infiltration capacity (VIC) model with the Palmer Index (PDSI) in central Iran. In this study, the components of water and energy balance in the Central Iran region were simulated using the VIC land surface model. The output components of this model, especially soil moisture after evaluation, were used as inputs in the drought index based on Palmer’s water balance. The integrated index of the VIC-PDSI in comparison with conventional Palmer indices and the SPI index at the 3, 6, 12, 24, and 48-month intervals was fitted with increments in moisture data and variations in the storage of water extracted from GRACE satellite data. Results showed that the combination of VIC-PDSI had the highest correlation coefficient of 0.87 with groundwater level change compared with other drought indices.