Prediction of Groundwater Storage under Climate Change Scenarios Using Meteorological and Hydrological Drought

This abstract presents the influence of meteorological and hydrological droughts on groundwater drought conditions through the calculation and analysis of four widely used drought indices: Standardized Precipitation Index (SPI), Reconnaissance Drought index (RDI), Streamflow Drought Index (SDI), and Groundwater Resource Index (GRI). These indices were computed using long-term observed data including precipitation, temperature, discharge, and groundwater levels to capture the temporal and spatial variability of drought events in the Chaliyar River Basin. By analyzing the spatial and temporal variability of groundwater levels and discharge rates and measuring the impact of future drought events under climate change conditions. The research utilizes historical data to understand the relationship between drought and groundwater availability, informing sustainable water management strategies. A Support Vector Machine (SVM) model was developed to simulate groundwater storage by using the Particle Swarm Optimization (PSO) to optimize SVM parameters. It begins with the collection of groundwater storage data, discharge data, and climate data, alongside outputs from global climate models (GCMs). The data is processed with a Gamma Test to determine the best combination of meteorological and hydrological drought indices as input variables. A Support Vector Machine (SVM) for groundwater simulation, which is optimized through Particle Swarm Optimization (PSO) to select the best SVM parameters. The developed SVM model undergoes validation using 5-fold cross- validation to ensure accuracy. Climate data downscaled for future scenarios, specifically RCP4.5 and RCP8.5, is then utilized to project drought events for the period 2022-2050. This enables an assessment of anticipated changes in groundwater storage and its behavior during future drought events under different climate conditions. This study investigates the interconnected effects of meteorological and hydrological droughts on groundwater storage in a changing climate. Using a combination of observational data, hydrological modelling, and climate projections, it assesses the impacts of drought on groundwater recharge and storage.