Estimating Crop Water Use via Remote Sensing Techniques vs. Conventional Methods in the South Platte River Basin, Colorado

Abstract

We compared two methods of estimating crop water consumption to assess whether remote sensing techniques provide consumptive use (CU) estimates commensurate with conventional methods. Using available historical satellite and meteorological data, we applied Mapping EvapoTranspiration at high Resolution using Internalized Calibration (METRIC) to 317,455 ha in the South Platte basin, in northeastern Colorado, for the 2001 irrigation season. We then compared these derived CU estimates with values calculated by using the Colorado Water Conservation Board's South Platte Decision Support System StateCU model. Evaluating the data by irrigation ditch service area, we disaggregated the output to allow for comparison by service area size, crop type, irrigation method, water supply source, and water availability. We concluded that METRIC is a suitable alternative to StateCU in the South Platte basin and could help to identify areas with inhibited crop growth or deficit irrigation practices. In addition, METRIC could be used as a complement to StateCU to refine StateCU model parameters, allowing for more accurate estimates of crop water shortages and groundwater recharge associated with irrigation delivery and application.(KEY TERMS: consumptive use; evapotranspiration; crop water use; remote sensing; water supply planning; water supply evaluation.)

Using Remote Sensing to Estimate Evapotranspiration of Irrigated Crops Under Flood and Sprinkler Irrigation Systems

“…In addition, the ReSET estimates of the different crops for 2001 were compared with the estimates of the METRIC and StateCU models for a study done by Burkhalter et al . () for the same year in the same study area. The p ‐values were found to be 0.128 and 0.576 for METRIC and StateCU models, respectively.…”

Sensitivity of evapotranspiration retrievals from the METRIC processing algorithm to improved radiometric resolution of Landsat 8 thermal data and to calibration bias in Landsat 7 and 8 surface temperature

“…ET images via METRIC provide the means to quantify ET on a field-by-field basis in terms of both the rate and spatial distribution. In the decade since the introduction of METRIC, the application has been adopted for use in Montana, California, New Mexico, Utah, Wyoming, Texas, Nebraska (Allen et al, 2007b;Kilic, A., I. Ratcliffe, P. Ranade, et al 2011b) and Colorado (Burkhalter et al, 2013), Nevada (Morton et al 2013), and Oregon (Trezza et al, 2011). The mapping method has enabled those states to negotiate water rights with Native Americans, assess impacts of water transfers from agriculture to urban uses, manage aquifer depletions, monitor water rights compliance, and manage endangered species.…”

Featured Collection Introduction: Assessing Consumptive Water Use via Satellite Data

“…The Burkhalter et al . () study provides a detailed comparison between ET measurements using the METRIC program and estimates developed by the conventional, Modified Blaney‐Criddle process widely used in Colorado, for 320,000 hectares of cropland in the South Platte River Basin. The results were encouragingly similar, but highlight the utility of METRIC in discriminating local areas of ET variation.…”