## 3 Results and Discussion
### Comparison of Measured, Estimated, and ITU-Recommended Rain Heights  
A comparison of the rain heights obtained from the recommended ITU model, the estimated seasonal rain heights, and the measured seasonal rain heights across the study stations is provided in Table 4. The estimated rain heights at all of the stations, as per the analysis, depict slightly higher values than the actual heights across all of the stations during the seasons. Percentage differences range from 0.02 to 5.30% depending on the chosen scenario, and the calculations shows a correlation coefficient of 0.997. The values within this range are higher, particularly during the winter and spring months. These seasons are usually characterized by low temperatures which expand the layers of ice and slow down the rate at which ice turns to water, thus adding to the width of the bright band known as the Melting Layer and decreasing the height of the rain in the troposphere. The estimated and the ITU-recommended rain heights are summarized in Table 4.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Station**} & \multirow{2}{*}{**Season**} & **Measured** & **Estimated** & **Estimated** & **ITU Hr** & **ITU \%** \\  & & **Hr (m)** & **Hr (m)** & **\% diff** & **(m)** & **diff** \\ \hline \multirow{4}{*}{Polokwane} & Autumn & 4816.65 & 4869.46 & 1.10 & 4621 & 4.06 \\  & Winter & 4459.62 & 4530.86 & 1.60 & 4621 & \(-\)3.62 \\  & Spring & 4934.11 & 4991.13 & 1.16 & 4621 & 6.35 \\  & Summer & 5270.98 & 5271.97 & 0.02 & 4621 & 12.33 \\ \hline \multirow{4}{*}{Nelspruit} & Autumn & 5031.37 & 5098 & 1.32 & 4498 & 10.60 \\  & Winter & 4387.76 & 4426.43 & 0.88 & 4498 & \(-\)2.51 \\  & Spring & 4610.02 & 4704.61 & 2.05 & 4498 & 2.43 \\  & Summer & 5096.92 & 5133.91 & 0.73 & 4498 & 11.75 \\ \hline \multirow{4}{*}{Pretoria} & Autumn & 4732.67 & 4776.72 & 0.93 & 4539 & 4.09 \\  & Winter & 4308.06 & 4357.36 & 1.14 & 4539 & \(-\)5.36 \\  & Spring & 4852.72 & 4899.9 & 0.97 & 4539 & 6.46 \\  & Summer & 5216.52 & 5220.39 & 0.07 & 4539 & 12.99 \\ \hline \multirow{4}{*}{Mahikeng} & Autumn & 5030.59 & 5095.07 & 1.28 & 4537 & 9.81 \\  & Winter & 4368.15 & 4401.02 & 0.75 & 4537 & \(-\)3.87 \\ \cline{1-1}  & Spring & 4651.5 & 4718.87 & 1.45 & 4537 & 2.46 \\ \cline{1-1}  & Summer & 5138.13 & 5153.62 & 0.30 & 4537 & 11.70 \\ \hline \multirow{4}{*}{Upington} & Autumn & 4918.51 & 4978.61 & 1.22 & 4458 & 9.36 \\ \cline{1-1}  & Winter & 4155.41 & 4183.98 & 0.69 & 4458 & \(-\)7.28 \\ \cline{1-1}  & Spring & 4387.61 & 4466.05 & 1.79 & 4458 & \(-\)1.60 \\ \cline{1-1}  & Summer & 5001.5 & 5047.81 & 0.93 & 4458 & 10.87 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Comparison of measured, estimated, and ITU-recommended rain heights.  
It was observed that the ITU value underestimates rain heights in all of the stations during the autumn, spring and, summer seasons. The recommended rain heights during the winter season are overestimated for all of the stations, except the coastal stations where Port Elizabeth and Cape Town rain heights are underestimated by 7.81 and 6.13%, respectively. The measured and ITU-recommended rain heights in Durban are approximately equal, with a negligible percentage difference of \(-0.35\%\). Comparative analysis of the measured seasonal and ITU-rec rain heights implies that the ITU performed poorly during autumn and summer, with percentage differences as high as 15.13%, 15.75%, 25.48%, 24.37%, 25.93%, and 33.17% during autumn and summer for the coastal stations. The measured seasonal and ITU-recommended rain heights presented in Table 4 possess a correlation coefficient of 0.598, which makes the estimate preferable.