Stochastic comparison of the effect of radiation and temperature on comsumptive use in a semi – Arid Region of Nigeria

Abstract

This paper focuses on the understanding of using empirical relations of radiation and temperature to model the effect of consumptive use in the semi – arid region of Nigeria, bearing in mind that the water demand of any agricultural field is determined by meteorological factors. Climate is the main stay in determining weather parameters like energy balance, humidity and vapour pressure deficit which affect the magnitude of vapour flux at the surface of the atmosphere. Some weather variables such as wind speed, relative humidity, solar radiation, temperature to a greater extent helps shape agricultural yield, hence the use of simple weather variables as radiation and temperature as an alternative in estimating evapotranspiration (ET). In this work, we modeled field consumptive use using empirical models of radiation and temperature base models and compared to the standard of the Food and Agricultural Organization (FAO) Penman – Monteith (PM) in the semi – arid region of Nigeria. The results showed that the empirical models of radiation and temperature have significant effect on the consumptive use. In Alkaleri Penman – Monteith (PM) correlated well with Baier-Robertson (B-R)(a) and Baier-Robertson (B-R)(b) at 75.0% and 88.2% respectively, whereas in Bauchi PM correlated with B-R(a), B-R(b) and J-H at 81.1%, 81.0% and 70.6% respectively. Therefore, the use of empirical models is an essential tool for modeling reference evapotranspiration in a semi – arid region in the absence of full meteorological data. Empirical models are veritable alternatives for the estimation, modeling and comparison because of its quality effect on the agricultural field.

Keywords: Radiation, Temperature models, semi – arid region, stochastic comparison