International Research Journal of Innovations in Engineering and Technology - IRJIET International Open Access, Monthly, Peer Reviewed, Reputed Journal ISSN (online): 2581-3048

Impact Factor (2025): 6.9

DOI Prefix: 10.47001/IRJIET

Daily and Seasonal Variations of Tropospheric Radio Refractivity at Akure in South-West Nigeria using Campbell Scientific Automatic Weather Instrument

Abstract

Tropospheric radio refractivity over Akure in South–West, Nigeria has been studied using meteorological data such as relative humidity, temperature and pressure from January 2014 – December 2016. The Campbell Scientific Automatic Weather Instrument was used for data collection and data was logged using the CR100 data logger. Measurement and data collection was done at a five minute interval. The records cover 24 hours each day starting from 00:00 hours to 23:55 hours local time. The overall three years data were averaged and used for the analysis. Results of the analysis show that the percentage contributions of the wet term of radio refractivity (which is a function of relative humidity) and dry term of radio refractivity (which is a function of pressure) were 29% and 71%, respectively. This revealed that variation of tropospheric radio refractivity over Akure is attributed to the contribution of the wet and dry terms of radio refractivity. The results also revealed that a regression statistical model can be used to predict radio refractivity in Akure using the available data.

Country : Nigeria

1 Agbo G. A.2 Onuorah L. O.3 Okoh D.

  1. Industrial Physics Department, Faculty of Science, Ebonyi State University, Abakaliki, Nigeria
  2. Industrial Physics Department, Faculty of Science, Ebonyi State University, Abakaliki, Nigeria and Department of Physical & Geosciences, Faculty of Natural Sciences & Environmental Studies, Godfrey Okoye University, Enugu, Nigeria
  3. Centre for Atmospheric Research, National Space Research and Development Agency, Abuja, Nigeria

IRJIET, Volume 4, Issue 2, February 2020 pp. 1-7

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