Fifty Years of Evaporation and Environment — Successes, Failures and Challenges for the Penman-Monteith Equation

This year, 2014, marks the fiftieth anniversary of the presentation at the annual meeting of the UK Society for Experimental Biology of the classic paper ‘Evaporation and Environment' by John L. Monteith. In it he extended Penman's combination equation to make it applicable for estimating transpiration from leaves and canopies. This paper will review the controversy that the Penman-Monteith Equation aroused, discuss some of the successes and limitations of the method for agricultural applications, and address the potential for using Monteith's work to explore how weather and climate influence crop water use and productivity.