American Southwest

The Rio Grande is one of the longest rivers in North America, running some 1,900 miles (3,060 kilometers) from the Colorado Rockies southeast to the Gulf of Mexico. It provides fresh water for seven U.S. and Mexican states, and forms the border between Texas and Mexico, where it is known as the Río Bravo del Norte. The river’s English and Spanish names mean, respectively, “large” and “rough.” But viewed from the Zaragoza International Bridge, which connects the cities of El Paso, Texas, and Ciudad Juárez, Mexico, what was once mighty is now a dry riverbed, lined ominously with barbed wire. The Rio Grande is one of the largest rivers in the southwest U.S. and northern Mexico. Because of drought and overuse, sections of the river frequently run dry. Kmusser/Wikipedia, CC BY-SA In the U.S., people often think of the Rio Grande mainly as a political border that f...

Humans have contended with dust storms for thousands of years, ever since early civilizations appeared in the Middle East and North Africa. But modern desert dust storms are different from their preindustrial counterparts. Around the world, deserts now increasingly border built structures, including urban dwellings, manufacturing, transportation hubs, sewage treatment and landfills. As a result, desert dust lifts a growing load of airborne pollutants and transports these substances over long distances. This is happening throughout the Global Dust Belt, an arid to semiarid region that stretches from western China through Central Asia, the Middle East and North Africa. Similar storms occur in the U.S. Southwest and central Australia. Global pattern of dust frequency estimated from weather records, 1974-2012. Shao et al., 2013, CC BY-ND To our thinking, modern desert dust storms have been overlooked...