Evapotranspiration equation standardization, what and why - a panel discussion

摘要

A panel has been assembled to discuss the merits and implications of having a recognized standardized evapotranspiration (ET) equation. A standardized evapotranspiration equation would be one that can be accepted by the United State's scientific community, water engineers, courts of law, policy makers and the end users. The selected equation would be one that could be used by both agriculture and landscape irrigation. In 1999, through activities of the Irrigation Association's (IA) Water ManagementCommittee, a request was initiated to the American Society of Civil Engineers (ASCE) Evapotranspiration in Irrigation and Hydrology Committee requesting the evaluation and recognition of such an equation. The request was to define and differentiate between short and tall reference crop ET procedures and to facilitate the use and transferability of crop and landscape coefficients.