The high mountains of central Chile look solid and eternal, but their ice is in trouble. For fifteen years, the country has endured a stubborn megadrought, and glaciers have quietly carried much of the burden. They have melted faster to keep rivers flowing and taps running. A new study warns that by the end of this century, that backup system may break when you most need it. An international team led by researchers in Austria, Switzerland and Chile set out a stark question: what if a drought as long and severe as today’s megadrought hits again near 2100? Their answer is blunt. The glaciers of the Southern Andes will be too worn down to cushion such a shock. Chile’s Long Thirst Chileans are used to periods of dryness. In the past, droughts came every five or six years and lasted one or two years. People could wait for rain to return. This time, relief never came. “Climate scientists only realized in 2015 that the unending drought in Chile was really a big thing,” says Francesca …