Climate change is accelerating the melting of the world’s mountain glaciers, according to a massive new study that found them shrinking more than twice as fast as in the early 2000s. The study drew on an international effort that included 233 estimates of changes in glacier weight. The world’s glaciers have lost more than 7 trillion tons of ice since 2000, according to the study. “The thing that people should be aware of and perhaps worried about is that yes, the glaciers are indeed retreating and disappearing as we said they would. The rate of that loss seems to be...