That word would be dry.
Xero is that word.
Yes, the word 'desert' 'desert' is a singular, common, concrete noun; a word for a dry, barren area of land, a word for a place.The word 'desert' is also a verb and an adjective.
that the desert probably had a wet climate at one time
The Sonoran Desert has a hot subtropical desert climate.
No one can answer that question unless you specify a particular desert. Each has its own climate.
It is not always a tropical desert. The climate in the southern part if the desert is a dry, tropical climate, while the climate in the northern part of the desert is a dry, subtropical climate.
Desert climate
Describe the essential features of the climate of the Mojave Desert?
No, it is not. A desert is a biome. A climate would be the meteorological conditions, such as "hot and dry".
Hot and arid desert
Tundra, believe me Tundra, believe me Tundra, believe me
The climate of an oasis depends on the climate of the surrounding desert. If the desert is hot, the oasis will be hot. If the desert is cool or cold, so is the oasis. If it is raining or windy in the surrounding desert, it will be the same in the oasis.