Uses
Orography has a major impact on global climate, for instance the orography of East Africa substantially determines the strength of the Indian monsoon. In geoscientific models, such as general circulation models, orography defines the lower boundary of the model over land.
When a river's tributaries or settlements by the river are listed in 'orographic sequence', they are in order from the highest (nearest the source of the river) to the lowest or mainstem (nearest the mouth). This method of listing tributaries is similar to the Strahler Stream Order, where the headwater tributaries are listed as category = 1.
Read more about this topic: Orography