Investigating feedbacks between regional irrigation and water energy budgets in the Little Washita Basin, Oklahoma
Geology and Geologic Engineering
Irrigation is the largest user of freshwater resources in the United States. Many locations rely on both surface water and groundwater resources to meet agricultural demand. Given the prevalence of conjunctive management, we seek to better understand feedbacks between groundwater, surface water and land energy fluxes and how they are impacted by irrigation. For this project we use the ParFlow integrated physical hydrology model. ParFlow is a powerful tool that is designed to run in parallel. It is ideally suited for this analysis because it has fully integrated groundwater and surface water systems, so we can directly analyze feedbacks that occur. We simulate the Little Washita Basin in Oklahoma, USA. Previous studies have shown positive correlations between groundwater depth and evapotranspiration. We build on this work by incorporating moisture dependent irrigation in order to better understand how groundwater pumping influences irrigation demand. We will run a number of 20 year simulations to investigate how the systems response to irrigation stress changes as a function of climate, irrigation intensity, and groundwater depletion.