Tucson’s drinking water supply — carries nearly 20 percent less water than in 2000. Bark beetles are chomping away at our forests and killing off ponderosa pines. Wildfires are rapidly growing in intensity. These problems have been linked to a drought that has stretched 19 years with no respite. Now, a team of researchers concludes that the ongoing drought across the western U.S. rivals most past “megadroughts” dating as far back as 800 A.D. — and that this region is currently in a megadrought.