Question

Why tropical deserts have tropical temperature

Answer 1

The tropical desert has the highest mean annual temperature of any climate on Earth. The high temperatures are a result of the high sun angles throughout the year and having the highest percentage of sunshine of any climate. No month has an average temperature below 18oC (64.4oF) and many places have consecutive average monthly temperatures in the mid 30os Celsius (90oF). Daytime temperatures can reach 50oC (120oF) at low elevation inland deserts.

The sky in the tropical desert remains cloud-free due to the subsiding air of dominant high pressure resulting in large amounts of insolation. The cloudless skies during the day lets insolation in, but also lets much heat out at night. Without the absorptive blanket of clouds, longwave radiation emitted from the Earth readily escapes to space, chilling the nighttime desert air. The high energy input during the day and large loss at night results in an extremely large daily temperature range.

And hence it has tropical temperature

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Answer 2

The tropical desert is an environment of extremes: it is the driest and hottest place on earth. Rainfall is sporadic and in some years no measurable precipitation falls at all. The terribly dry conditions of the deserts is due to the year-round influence of subtropical high pressure and continentality. 

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