Major hot deserts in the northern hemisphere are located between 20-30 degrees north and on the western side of the continents. Why?

Location of hot deserts:

this zone is marked by the sub-tropical high pressure zone, reinforcing mechanical high pressure, due to subtropical westerly jet stream.

this causes atmospheric desiccation, leading to doudless skies, high winds (gaining effect) and negligible precipitation

(ii) Western side of continents → this can be attributed to 5 reasons:

(a) Offshore winds → the peripheral trade winds are offshore, thus no land-use blow from land to sea. No moisture → no rainfall.

(b) Cold upwelling surge → due to density upswelled → upwelling of cold bottom waters → strengthens high pressure, produce drying effect on coastal deserts.

Thus, most tropical deserts are found in a certain specified belt due to various complementary ocean-atmospheric interactions.

— Ritika Chitlangia