The Delimitation of Homogeneous Rainfall Regions In the Southeastern Transvaal

Meaningful research relating to factors influencing crops and yields, is facilitated when undertaken in small homogeneous regions. Recent methods employed in delimiting homogeneous rainfall regions include those using simple grouping procedures and mapping of loadings resulting from S-mode PCA. These methods were applied to the same data set, consisting of 60 years (1917–1977) annual rainfall values for 60 rainfall recording stations in the South Eastern Transvaal, and the results compared. It was found that the techniques employing simple grouping procedures and PCA loadings yielded satisfactory and comparable results and therefore either method can be used for delimiting small homogeneous rainfall regions.