ScienceNews: When did you first learn high-elevation glaciers were dying? When we started our monitoring program in 1978, people typically described the movement of ice fields as slow – you know, glacial. But in the early ’90s during repeated visits to Peru’s Quelccaya glacier, the largest tropical ice cap on Earth, we realized it was in rapid retreat. Although 168 meters thick at the top, it’s now retreating up the mountainside by about 18 inches a day, which means you can almost sit there and …