How Much of the World Is Covered by Deserts?

Approximately one-third of the Earth's land surface is covered by deserts. These arid regions are defined by receiving very little precipitation—typically less than 250 millimeters (10 inches) of rainfall per year. Deserts are characterized by sparse vegetation, extreme temperature fluctuations, and a lack of permanent water sources.

The world's largest deserts include the Sahara in Africa, the Arabian Desert in the Middle East, and the Gobi Desert in Asia. While deserts can be found on every continent, Antarctica is technically classified as a polar desert due to its extremely low precipitation levels, though it's often excluded from general desert classifications.

Despite their harsh conditions, deserts support unique ecosystems with specially adapted flora and fauna. They also play important roles in global climate patterns and mineral resource distribution.