Evaporation from Shallow Water and Related Micrometeorological Parameters

Abstract

During the spring of 1961, experiments were conducted at the U.S. Water Conservation Laboratory, Tempe, Ariz., to measure the magnitude of evaporation and related micrometeorological factors from isolated shallow water and an extended shallow water. The data obtained were analyzed using the energy balance equation ????????????????Rn+S+W+LE+A?=?0, where Rn is the measured net radiation, S is the measured soil heat flux below the water layer, W is the calculated change in heat storage of the water layer, LE is evaporative flux determined from sensitive weighing lysimeters, and A is the sensible heat flux to the air obtained from the solution of the energy balance equation. The results of triplicate measurements made every 15 minutes for seven consecutive days indicate that the evaporative flux is larger from the isolated shallow water. The daily totals of the sensible heat flux to the air indicate that energy was derived from the air in all cases for the isolated shallow water, and energy was used to heat the air in the case of the extended shallow water.