The desert breathes. The most common views of Arizona show one of three things; the Grand Canyon, Monument Valley or the Arizona-Sonora Desert with saguaro cactus. Actually, a substantial portion of the state is forested and well above 5000 feet. For example, both rims of the Grand Canyon are forested in their most popular parts. A most dramatic feature of the state is the Mogollon Rim, actually the southern-western edge of the Colorado Plateau. This 1000 to 2000 foot escarpment is highly visible in central Arizona and around the Sedona area.
The huge elevation changes create a significant atmospheric phenomena called katabatic winds. These winds arise in any area of the world where there are differences in altitude but are particularly regular and significant along the Rim. During the daytime, especially in the warmer months, the temperature gradient between the top of the Mogollon Rim and the deserts below can be 40 or 50 degrees Fahrenheit or more. This vast temperature difference means that during the daytime, the hot desert air rises up through the canyons and finally blows out at the top of the Rim. In the night, the cooler air on the Rim sinks down through the canyons and blows out onto the desert.
You would think that the cooler air from the mountains would be a welcome relief, but as the air descends it is heated adiabatically, so that in the lower deserts, the wind feels warm and sometimes hot.
Camping on the Rim during the summer, the wind picks up in the early evening and blows up the canyons, in the morning the air is calm. Camping in the desert, you get the reverse, in the evening the air will be calm, but by morning there is a breeze which last until the sun comes fully up and starts to heat the ground again.
In our rush, rush modern world, perhaps it would be nice just to experience the daily breathing of the deserts.
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