Question

why most of the world's deserts are located in the western margins of continents in the subtropics?

Answer 1

Deserts are most common in the western margins of the continents in the tropics.Because of the cold ocean currents along the western margins of the continents.The air that blows over the cold ocean currents becomes cold and thereby the moisture is sucked, this makes the region devoid of moisture and rainfall.The prevailing winds in the tropics are tropical easterly winds, the tropical easterly winds become dry by the time they reach the western margins of the continents and so they bring no rainfall.  

Answer 2

Answer:

Most of the worlds deserts are located in the western margins of continents in the subtropics because the prevailing winds in the tropics are tropical easterly winds. The tropical easterly winds become dry by the time they reach the western margins of the continents and so they bring no rainfall.