According to some newly published research in the peer-reviewed Journal of Climate, the Sahara Desert has expanded by 10 percent since 1920. Many deserts form in the belt of sinking air located around 30 degrees N and S latitude. This sinking air is associated with the Hadley cell, a vertical circulation of air linked to rising heated air in the tropics near the equator and sinking are at 30 N and S. The research indicates that the spreading of the desert band may be linked to an expansion of the Hadley cell, possibly by a warming climate. You can read more here.
