William deBuys is the author of seven books, including the just published A Great Aridness: Climate Change and the Future of the American Southwest (a Pulitzer Prize finalist), and The Walk (an excerpt of which won a Pushcart Prize). He has long been involved in environmental affairs in the Southwest, including service as founding chairman of the Valles Caldera Trust, which administers the 87,000-acre Valles Caldera National Preserve in New Mexico.