Despite being covered in ice, Antarctica is actually considered a desert and is drier than the Sahara. The key factor in classifying a region as a desert is its low precipitation levels. Antarctica receives very little moisture, averaging about 2 inches (50 mm) of precipitation annually, primarily in the form of snow. In contrast, the Sahara Desert averages around 4 inches (100 mm) of rain each year, but this rain is irregular and can be quite sparse in many parts of the desert.
Furthermore, the extreme cold of Antarctica means that the moisture that does fall doesn’t evaporate, contributing to the arid conditions. The interior of Antarctica is particularly dry and windswept, which limits the moisture retention in the air. On the other hand, while the Sahara is hot and arid, it does receive more rainfall than Antarctica, particularly in the northern and southern edges.
In summary, when considering average annual precipitation, Antarctica is indeed drier than the Sahara Desert, showcasing how the classification of deserts can be surprising.