The text boxes below have been placed in a random order. Reorder the paragraphs.
(A) The dry, warm and dust-laden winds are sometimes felt north and south of the desert, where they are variously known as sirocco.
(B) Located in the trade winds belt, the region is subject to winds that are frequently strong and that blow constantly from the north east between a subtropical high-pressure cell and an equatorial low-pressure cell.
(C) Sahara is one of the harshest climates in the world.
(D) As air moves downward from the high pressure cell to the low pressure cell,So it becomes warmer and drier.