Columnar Radio Refractivity Of The Troposphere At Ashodi And Kano

Abstract

Spatial-temporal, distributions of columnar radio refractive index in the troposphere of two tropical stations – Kano and Oshodi are considered. Monthly means of radio refractivity have been shown for the atmospheric columns, 0 – 3km (the lower atmosphere), 0- 10km (the first 10km column), and 3-10km (the upper atmospheric column). Correlation coefficient between monthly means of surface radio refractivity N_s and refractivity at each of the atmospheric columns N_L, N_T and N_u (refractivity values for 0-3km, 0-10km, 3-10km respectively) is higher than 0.9 at Kano and 0.7 at Oshodi in most of the cases. Equations of regression have also been obtained by means of which measurements of N_s can be used to estimate the refractivity gradient δN of the first one kilometer over each of the two stations and other places in the same climate zone.

KEY WORDS: Columnar radio refractivity, correlation coefficient, refractivity gradient, troposphere, torpical

Global Journal of Pure and Applied Sciences Vol.11(2) 2005: 305-307