Correlation and Regression Analyses of Refractivity with Metrological Parameters in JOS
The paper studies the variation pattern of refractivity on land with the three major metrological parameters. The measured refractivity was compared with measured temperature, pressure and relative humidity at 100m height. The data were collected at interval of 30minutes for the whole day. Exponential, linear, power series, logarithmic and polynomial regressions were used to analysed the data and predict the refractivity in a day over the eight months in Jos of Nigeria. Correlation analyses were also used base on the predicted regression equations for two months each represents early dry season, late dry season, early rainy season and late rainy season.The study shows that refractivity increases with pressure and relative humidity while decreasing with temperature. The best regression equation of refractivity with pressure, temperature and relative humidity is polynomial equation. The correlation of pressure, temperature and relative humidityranges from 0.2067-0.7291, 0.2242-0.9061 and 0.6741-0.9686. The correlations in early rainy and dry seasons for humidity and temperature and late rainy for pressure have highest value. Other regression equations for humidity and temperature have better performance and worst in pressure.
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