evidence: The world's glaciers are melting at an accelerating rate, according to a comprehensive new study. [...] The researchers found them to have lost almost 270 billion tonnes of ice a year over the opening two decades of the 21st Century. [...] Leeds professor Andy Shepherd told BBC News: "Glacier melting accounts for a quarter of Earth's ice loss over the satellite era, and the changes taking place are disrupting water supplies for billions of people downstream - especially in years of drought when meltwater becomes a critical source.