Why do deserts exist and why are they all north of the equator?


Specifically in reference to places like Arabia. It’s a peninsula surrounded by water but also all of north Africa. Southern Europe isn’t desert as far as I’m aware so what’s going on there?

In: 1

well, first, not all deserts are north of the equator. in fact, the single largest desert on earth is antarctica.

as for why is the arabian desert so dry, it’s mostly down to wind currents. the land around the arabian peninsula is mostly dry, so there isnt much moisture to evaporate to form clouds capable of causing rain in the arabian desert. the bodies of water surrounding the peninsula lack sufficient surface area to make any meaningful rainfall.

Your concept of the world must be a little distorted if you think that the world consists of north Africa and Europe. Considering that the definition of a desert is low precipitation, Antarctica is the largest desert. But even with hot deserts, you have deserts in the south like the Kalahari Desert in Africa, the Patagonian Desert in South America, and most of the continent of Australia.

As for while certain areas have low rainfall, just to keep it to an ELI5 level, it has to do with air currents. There are “cells” of currents in the atmosphere, which creates wind patterns that generally go in a similar direction in specific latitudes. As wind goes across bodies of water, it becomes more moist and cool. As they go over land, the moisture is lost as precipitation (e.g. rain). Consequently, areas further inland tend to be more dry and have more deserts (Asia, Africa, Arabia).

There are also “rain shadow” deserts. These are located on the other side of mountain ranges. Wind carries moist air inland, but the presence of mountains forces the air to rise. As it rises, it loses its moisture, with the rain falling on the near of the mountains. The air on the far side of the mountains is drier, causing desert conditions.