Dewfall and Evapotranspiration Determination during Day- and Nighttime on an Irrigated Lawn

Abstract

Dewfall and evapotranspiration have been measured with a weighable lysimeter and computed through the energy balance equation, during day and nighttime; the Kazanskiy-Monin nomograph has been used for parameterizing the air sensible heat flux. The experimental data have been taken on a flat lawn, starting after an irrigation. The results show that the values of the computed mean net water flux are always significant, that is, their signs are always unambiguous. There is a general good agreement between derived and measured water fluxes, and a good coincidence between derived and computed dew onset, dew ending and dew duration.