Incorporating irrigation parameterizations into a regional climate model.

In this study, two parameterizations for different irrigation techniques have been implemented in a regional climate model. These implementations allow for a comparative study of water use and land–atmosphere interactions associated with traditional flood irrigation—a widespread but highly water-inefficient practice—and water-conserving drip irrigation. Both parameterizations yield realistic results for coupled climate simulations, and do so without the need to reproduce an entire crop model within the climate model. Simulations with drip irrigation exhibit 30% less irrigation season evapotranspiration and 60% less water demand overall relative to simulations with flood irrigation.