Water resource managers rely on hydrologic planning and decision-making models to understand and evaluate current and future water operations in the face of endangered species needs, drought, and climate change. Current climate change projections, such as those used in the West-Wide Climate Risk Assessment programs, are trending toward more extreme instances of drought within the Southern Rockies LCC region. Accurately estimating agricultural water consumption both under present conditions and under modeled future scenarios will help water resource managers project how much water might be available for allocation toward current ecological projects. It will also improve their understanding of the challenges a more water-limited future will present.
In most western states, approximately 80 percent of water withdrawals are for agricultural use, and this holds true for the Rio Grande Valley as well. However, the current models that are used to calculate the amount of water depleted by agriculture either rely on locally calibrated methods that are decades old or on generic reference evapotranspiration (ET) methods that must be calibrated on a gross level to determine actual water depletions. Advancements in technology and the understanding of water use require improvement and updates to many aspects of these models to ensure these future scenarios are accurate. The hydrologic models used in the Rio Grande Basin (including the Upper Rio Grande Water Operations Model and the Upper Rio Grande Simulation Model) rely on standard potential crop coefficients to estimate potential crop water use. These models require separate empirical calibration to match historical stream flows, largely because they tend to overestimate crop ET.
FY2012Water resource managers rely on hydrologic planning and decision-making models to understand and evaluate current and future water operations in the face of endangered species needs, drought, and climate change. Current climate change projections, such as those used in the West-Wide Climate Risk Assessment programs, are trending toward more extreme instances of drought within the Southern Rockies LCC region. Accurately estimating agricultural water consumption both under present conditions and under modeled future scenarios will help water resource managers project how much water might be available for allocation toward current ecological projects. It will also improve their understanding of the challenges a more water-limited future will present.
In most western states, approximately 80 percent of water withdrawals are for agricultural use, and this holds true for the Rio Grande Valley as well. However, the current models that are used to calculate the amount of water depleted by agriculture either rely on locally calibrated methods that are decades old or on generic reference evapotranspiration (ET) methods that must be calibrated on a gross level to determine actual water depletions. Advancements in technology and the understanding of water use require improvement and updates to many aspects of these models to ensure these future scenarios are accurate. The hydrologic models used in the Rio Grande Basin (including the Upper Rio Grande Water Operations Model and the Upper Rio Grande Simulation Model) rely on standard potential crop coefficients to estimate potential crop water use. These models require separate empirical calibration to match historical stream flows, largely because they tend to overestimate crop ET.