Submitted to: Irrigation Association Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/8/1999
Publication Date: N/A
Citation: Interpretive Summary: This paper is a summarization of state contacts and methods used by various groups, agencies, and weather station networks to calculate water use from crops and from turf grass. The material will be placed on a Web site so it can be maintained and updated regularly and for wide distribution to the irrigation industry. The paper introduces the concept that the American Society of Civil Engineers is working with the Irrigation Association to develop a more unified and consistent basis for representing the basic water use rates from crops and turf grass called the "reference evapotranspiration." The paper provides a detailed list of contact individuals that can provide assistance in interpreting and providing data to estimate water use information for irrigation design and for irrigation management.
Technical Abstract: Most modern evapotranspiration (ET) methods rely on the relationship between energy available for evaporation of water to predict the corresponding ET rate. Various formulations and approaches have been used across the United States during the past century. ET information is critical for system design (application rate and flow rate) and for water management (irrigation scheduling, salinity control, etc.). However, it has been difficult for end users to obtain local ET information in many cases. This report provides a list of contacts within the U.S.A. where ET information can be obtained. This list will change and evolve to remain current in each state. An update is also provided on activities within IA and ASCE to produce a standardized procedure for calculating reference evapotranspiration. This standardization is intended to facilitate interchange of ET information.