Deserts of North America

The Mojave Desert

The Mojave Desert reaches from the eastern slopes of the Sierra Nevada, a mountain range in eastern and southeastern California, to the Colorado Plateau, covering portions of Arizona, Nevada, and Utah. It has a typical mountain and basin desert topography with very little vegetation compared to other deserts of North America. However, it does have one signature plant, the Joshua tree, which is actually part of the yucca family. The Mojave Desert—and more specifically, Death Valley—is also well-known for having the lowest absolute elevation and the recording of the highest maximum temperature (134°F, or 57°C).

The Sonoran Desert

The Sonoran Desert covers the western half of the state of Sonora, Mexico, as well as most of Baja California; it then stretches into southeastern California and southwestern Arizona for a total of roughly 100,000 square miles. The geography of the Sonoran Desert consists of broad, flat valleys and small, rocky mountain ranges. It is milder than the other North American deserts and receives more rainfall due to summer monsoons, creating a lush landscape suitable for columnar cacti (saguaro)—its most notable plant—as well as yuccas, ocotillos, century plants, palo verde trees, and a diverse variety of cacti. The Sonoran Desert does have an area that is more typical of a desert. The lower Colorado River region, the boundary between California and Arizona, receives very little rainfall and experiences temperatures in the summer close to 120 °F (49°C).

The Chihuahuan Desert

The Chihuahuan Desert is the largest desert in North America, spanning 200,000 square miles in southeastern Arizona, southern New Mexico, and southwestern Texas, then down into northern Mexico (its largest area). It is a high desert, relatively speaking—most of it sits at elevations between 3,500 and 5,000 feet above sea level. Because it covers such a large area, its geography and geology are not easily characterized. However, limestone and calcareous deposits are prevalent in the region. It experiences extremely hot summer temperatures and erratic and intense summer monsoonal rainfall (still fewer than ten inches a year). The Chihuahuan Desert is characterized by its vegetation, an assortment of cacti, such as agave and prickly pear, and mesquite. Large areas of the desert region are occupied by Native American reservations. The area has become a popular location for military installations, which use the remote and barren land in a variety of ways. Tourism has also become extremely prevalent in the area, and the influx of people is causing new issues, such as a need for water, on an already stressed environment.