Revision of Oregon crop water use and irrigation requirements
A project to revise the crop water use estimates and irrigation requirements for the state at Oregon is described. The FAO modified Blaney-Criddle method was applied in this project since this method has been shown to have the lowest estimation error of all temperature-based methods when compared with lysimeter measurements. In addition to computerization of the meteorological data base, a set of computer programs were developed to perform the analysis and to apply the FAO crop coefficients to the reference evapotranspiration results. The first product of the project were tables of crop water use and net irrigation requirements. A series of contour plots of monthly reference evapotranspiration over the state for use by water resources planners and hydrologists was also developed. Examples of the project output picked at random from the published results are described.