Abstract :

In this study, the monthly averaged daily mean temperature, relative humidity and surface pressure data obtained from the European Centre for Medium-Range Weather Forecasts (ECMWF) during the period of thirty eight (1979 – 2016) years were used to estimate the monthly variation of geopotential and scale heights for Iseyin located in the South Western region of Nigeria. The variations of geopotential and scale heights with the meteorological parameters were investigated. The results revealed that the highest and lowest values of geopotential height were found in the months of March and July with 194.2424 m and 157.3922 m respectively while the highest and lowest values of scale height were found in the months of March and August with 8.8946×〖10〗^3 m and 8.7825×〖10〗^3 m respectively. Furthermore, it is obvious that high values of geopotential height were recorded during the dry season and low values during the rainy season; the scale height shows almost close observation. The variation of geopotential and scale heights with mean temperature depicts a direct relationship while the variation of geopotential and scale heights with atmospheric pressure depicts an inverse relationship. In addition, the variation of geopotential and scale heights with relative humidity shows that an almost opposite pattern of variation was observed in the months from May to October.

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Keywords :

ECMWF, Geopotential Height, Iseyin, Meteorological Parameters, Scale Height

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