Development of Model for the Estimation of Weighted Atmospheric Mean Temperature in Benue State, Nigeria

Weighted Atmospheric Mean Temperature (Tm) is the average mean temperature of precipitable water vapour in a given column of the atmosphere. Precipitable water vapour is the amount water present in a given column of the atmosphere. It is vital in weather forecasting and radio communication links. It forms the basis for understanding atmospheric dynamics; which is vital for wind tunneling in aircraft designs. Accurate measurement of Tm is central to the estimation of precipitable water vapour. In Benue State, a sub-Sahara region of West Africa, which lies between latitude 6.5 – 8.5 0N and longitude 7.47 and 10 0E respectively, is driven by convective activities and the movement of the Inter-Tropical Discontinuity (ITD). In this region, Atmospheric stations equipped with radiosonde for direct measurement of Tm are very scarce and do not have wider coverage of data collection over time. Hence, it has become imperative to infer Tm from satellite data to develop models that would cover for the data gap. Using eleven-year monthly averaged data from Climate Monitoring Satellite Application Facility (CM-SAF), for eight stations in Benue State, an empirical model of the form Tm = aTs + c (where Tm is the weighted atmospheric mean temperature, Ts is the surface temperature and a, c are constants) were found to be the best model estimation of Tm for Benue State. The model was found to agree with other similar models found for other regions of the world and upon validation with in-situ (Radiosonde) measurements the model was found to have a MBE of 0.034K and RMSE 0.072K.