A certain groundhog is fond of predicting the end of the east coast’s winter – but it is unclear if these augurings have any bearing on the Sonoran desert, thousands of miles away. Perhaps the generalities of large-scale climate oscillations (El Niño, for example) couple these two parts of the world. This year the groundhog…

Who, or what, crosses over to the United States? The Border Patrol operates this blimp out of Sierra Vista, less than twenty miles from Mexico. Its purpose is officially radar surveillance – the detection of low-flying aircraft smuggling drugs and other cargo. But imagine if the blimp also provided infrared (heat-sensitive) images. It would surely…

Spring is here, though the calendar and a certain groundhog may disagree. In the desert, this time of year is associated with floral blooms. Many species grow and reproduce in these cool months, but only when enough moisture is present. In dry years, many seeds remain ungerminated in the soil; in wet years, growth proceeds…

Ghosts of the past appear when walking through the Luquillo forest. Take the cable bridge across the Quebrada Sonadora and hike uphill half a kilometer, and you will soon find the remains of a stout metal fence. It is decaying now, but once served a purpose: keeping people out of a highly radioactive area. In…