Why has wind erosion shaped so many landforms in the American Southwest?

Question

For my daughter's homework. Harcourt Science Book IL level 5

Answer 1

The region is too dry to support a thick cover of vegetation that would dampen the effects of wind. A windstorm in a forest is a rather different matter than a windstorm blowing across the desert. In the desert, the wind can easily pick up loose sand. Blowing sand on unprotected rocks is nature's version of sand-blasting.

Answer 2

Because its so dry and thats where the jet stream usually goes through.