The catchment area of the Oranje river underlays with climate zones according to Koeppen - Geiger
<a href="//commons.wikimedia.org/wiki/User:Peter_in_s" title="User:Peter in s">Peter in s</a>, Beck, H.E., Zimmermann, N. E., McVicar, T. R., Vergopolan, N., Berg, A., &amp; Wood, E. F.
CC BY-SA 4.0
<a href="//commons.wikimedia.org/wiki/File:Koppen-Geiger_Map_Africa_present.svg" title="File:Koppen-Geiger Map Africa present.svg">File:Koppen-Geiger_Map_Africa_present.svg</a>