Abstract:
Radar provides a unique tool to measure the precipitation with a large aerial coverage. Satellite communication links operating at frequencies above 10 GHz are affected immensely by hydrometeors such as rainfall. These effects are expected to be quite severe in the tropical region like Akure. The remote sensing of precipitation is very important for radio communication applications. Interpretation of radar reflectivity to derive rain information is however, complex due to the presence of various rain structures. Information on vertical rain structure is important for accurate quantitative precipitation estimation. Thus, the focus of this work is to determine the vertical rain structures using vertically-pointing Ka-band Micro Rain Radar-(MRR) at Akure, Nigeria. This has been achieved by using 2-year (2013 and 2014) archived data of tropical rain parameters namely: rain rate (RR), reflectivity (Z), liquid water content (LWC) and fall velocity (W) obtained from MRR to determine the bright band heights under different rain types and its implications on satellite and radio waves propagation in this region. The MRR is sited at the Department of Physics, Federal University of Technology Akure (Lat 5°15'E, long 7°15'N). Rain rate in this region has been categorized into four groups namely: 0.02- 0.2 mm/h, 0.2- 2 mm/h, 2-40 mm/h, 40- 200 mm/h. The very low rain rate group is related to the stratiform rain types whereas highest rain rate groups are for the convective rain type. The result shows that parameters that are much associated with rain (LWC, W, and RR) attained peak value at different height depending on the period of the year. The vertical profile of Z shows peak around 3 to 4.2 km height. The peak region is associated with the bright band and contribution to the melting layer. The overall results will be useful for determining rain height for this region.
