I think this is the answer...
Warm air is increasing to create low pressure zone; cool air is falling, creating a high pressure region. Air pressure and climate are rising warm air. Winds cause weather that moves across high-and low-pressure areas horizontally. The faster the wind moves, the higher the pressure difference between the pressure zones.
Typically associated with a Cold front
I am absolutely sure that <span>the percent of the Sahara Desert is covered by sand sheets and dunes is definitely 25 %. Even though it might seem weird, it is actually correct and here are the pic from artcicle about Sahara which will pose as a proof : )
Do hope it will help!
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