What causes patagonia to be dry , barren and windy

Patagonia is dry because it lies in the rain shadow resulting from high mountain range of the Andes rising on the western side of this desert. The Andes block the westerly flow of moisture from the southern  pacific from reaching the inland areas thus creating the desert.

The cold Falkland current found that is found off the Atlantic coast of south America also contributes to the aridity of the area.

The Patagonia desert occupies 673, 000 square km and is the largest desert in Argentina  and 7th largest in the world by area.

since there isn't any suggested answers i will give you the reason and hopefully you can figure it

south africa, or rather all of africa, has not been in the location in which it is nowadays throughout the geological past. after the super-continent pangaea started to break apart, gondwanaland, in which was africa, moved further south, and parts of it came to be very close to the south pole. because the climate in this part of the world is very cold due to the very dispersed sun rays in there, what is now south africa, started to freeze, and the conditions were right for the formation of glaciers. the glaciers existed up until the period when gondwanaland started to break apart and what is now africa started to move towards north, sp it warmed up and the glaciers melted.