Some studies of sensible and latent heat fluxes at waltair, southeastern coast of India

Abstract

Sensible and latent heat fluxes are estimated over a 22-month period at Waltair (latitude 17°42′N, longitude 83°18′E) using three methods: Halstead's (1954) model of non-equivalence of turbulent transfer coefficients, the classical concept of equivalence of turbulent transfer coefficients, and by use of the Bowen ratio. The computations show that Halstead's method is best in the evaluation of sensible and latent heat fluxes. Agreement of fluxes obtained by the Bowen ratio method and Halstead's method is best during daytime and poor during night time. The diurnal, seasonal and annual variations of the sensible and latent heat fluxes are discussed. During the monsoon and postmonsoon periods, the latent heat flux is higher than the sensible heat flux, while the reverse conditions prevail during the winter and summer. The annual values of sensible and latent heat fluxes are in good agreement with net radiation. A relation between the Bowen ratio and the mean moisture content of the top 30 cm soil-layer is established. The Bowen ratio reaches a limiting value as the moisture content in the soil increases to field capacity.