Why do deserts often get very windy?

Deserts usually have few trees or tall plants to slow the air, so winds can travel with little friction across broad open surfaces. Temperature contrasts between day and night, and between land and surrounding regions, can also create pressure differences that drive winds. Those winds can pick up dust and sand, forming dunes, abrasion features, and dust storms. In some deserts, wind is one of the main forces shaping the landscape.