Fig. 5 (top graph) shows the semiva

Fig. 5 (top graph) shows the semivariogram of annual rainfall computed from the 36 data of Fig. 4.
Because of the lack of data only the omnidirectional semivariogram was computed, and hence the spatial
variability is assumed to be identical in all directions. Semivariogram values increase with the separation
distance, reflecting our intuitive feeling that two rainfall data close to each other on the ground are more
alike, and thus their squared difference is smaller, than those that are further apart.