A desert is a
place that receives little or no precipitation. Although we think of deserts as
hot places, they can be cold regions too.
To be considered a
desert an area must have less than 250 millimeters of annual rainfall. Using
that criteria, the continent of Antarctica is the largest desert on Earth. It
has less than 51mm of precipitation per year and little or no vegetation. The
Antarctic Desert is the largest on Earth at 13.8 million sq km. In comparison,
the Sahara is only 9.1 million sq km.
