Comparative Observations of Different Types of Evaporimeter

Abstract

The present authors have made the experiments of the evaporation by the open pan evaporimeter which is used generally in meteorological observatory and other three types of evaporimeters: namely the evaporimeter made by Fujiwhara and Takahasi (see Fig. 1 & 2) which was previously reported in this magazine, the porousporeclain atmometer by Livingston (Fig. 4) and the cylindrieal filter paper atmometer by Daigo with principle of Livingston's atmometer (Fig. 5). The results of experiments showed that the amounts of evaporations of these evaporimeters were linearly eorrelated each other.
It was also found from the experiments that differences of amounts of evaporations of various evaporimeter were caused mostly by differences of absorption of radiation.
Therefore the color of evaporating surfaces or of mounting of evaporimeter itself should be kept as constant as possible.