Why Is Most of Egypt Desert? Rain Shadows, Subtropical Sun & the Nile Exception

Egypt's aridity has two main drivers:

1. Rain shadow of the Ethiopian Highlands – Prevailing northwesterly winds rise over the highlands, cool, and drop moisture on the Ethiopian side. By the time air reaches Egypt, it's hot and dry.
2. Subtropical latitude – Intense solar radiation heats ground and air, evaporating soil moisture. High temps + low rain = desert.

The exception: The Nile Valley and Delta. The river brings water from tropical Africa, enabling irrigation and a narrow green corridor where 95% of Egyptians live. Without the Nile, Egypt would be virtually all desert.