Explain why the amount of rainfall a region receives is a better determination of whether it is a desert than temperature.

As there are many kinds of deserts, some hot, some cold even arid deserts are the classic hot deserts, but there are also cold and coastal deserts where temperatures do not get so high. The element common to all of these types of deserts, however, is their lack of rainfall. In that sense the rainfall is a characteristic that determines if it's a desert.