What factor distinguishes a midlatitude desert (bwk) climate from a subtropical desert (bwh) climate?

The factor that distinguishes a midlatitude desert (bwk) climate from a subtropical desert (bwh) climate is, "BWk climates are located more poleward than BWh climates".

The midlatitude desert is viewed as a parched atmosphere in which the aggregate yearly precipitation is not as much as a large portion of the yearly potential evapotranspiration. Precipitation is inadequate as the inside area is inaccessible from a wellspring of dampness. Or then again, the absence of precipitation is because of its leeward, rain shadow area. 
A subtropical desert is a sort of biological system, or biome that is described by high temperatures, low precipitation and warm soils. Cases of these sorts of deserts are the Mojave, Sonoran, Chihuahuan, Sahara and the Great Victoria Deserts.

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