The biggest desert in the world is Antarctica. It covers an area of 14,000,000 km2 (5,400,000 sq mi). Most people think of a desert as a hot place. However, any area that gets very low precipitation qualifies, so by that definition, Antarctica will fit.
Facts about Antarctica
Rainfall in Antarctica has been estimated at 20 millimeters (0.8 in) annually. This happens due to the cold temperature. Almost all water rapidly freezes and turns to ice. Most of the liquid in Antarctica is set a mile below its surface. Due to pressure, liquid lakes can be found in spite of the freezing climate.
There are two large rivers in Antarctica, Onyx and Alph. Onyx is the longest on the continent at 30 km (18 mi). The Nile River on the other hand, is 6,650 km (4,135 mi) long. Antarctica is not just the biggest desert in the world; it is also one of the most ancient. It was formed 53 million years ago.
The Sahara Desert
The largest non-polar (or “hot”) desert is the Sahara. Situated in Africa, it covers an area 9,100,000 km2 (3,320,000 sq mi). The Sahara spans ten nations: Tunisia, Sudan, Morocco, Mauritania, Niger, Mali, Libya, Egypt, Chad and Algeria. The Sahara encompasses most of North Africa. It is almost as big as the US.
The Sahara extends from the Red Sea all the way to the oceans of the Atlantic. The Sahara is the site for the hottest temperature recorded on the planet. On September 1922 in Libya, the temperature reached 58 C (136 F).
The Arabian Desert
The Arabian Desert is the third largest after Antarctica and the Sahara. Located in the Middle East, it encompasses an area 2,330,000 km2 (900,000 sq mi). It spans ten nations in the Middle East: Yemen, Oman, the UAE, Qatar, Kuwait, Iran, Iraq, Jordan and Saudi Arabia. Majority of the world’s oil reserves are located here.
Pangaea is the name given to a large continent dating back some 300 – 150 million years ago. Scientific estimates say its desert interior was seven times bigger than Antarctica. However, this land in all likelihood was unsuitable for life. But it should be stated that the dimensions given for Pangaea are only estimates.
While Antarctica is the biggest desert in the world, it is not the largest in the Solar System. That would be the planet Venus. That planet’s atmosphere only has .002% water vapor. Scientists believe the surface there is 460 C (860 F).