Global warming has increased the rate of melting of Greenland's glaciers fivefold over the past 20 years, researchers from the University of Copenhagen reported on November 10. Greenland's melting ice is of particular concern because the ancient ice sheet holds enough water to raise sea levels by at least six meters if it were to melt completely. A study of a thousand glaciers in the area showed that the rate of melting has entered a new phase over the past two decades, Anders Anker Bjork, an assistant professor at Copenhagen University's department of geosciences and natural resource management, told Reuters. "There is a very clear correlation between the temperature we're experiencing on the planet and the changes we're seeing in how fast the glaciers are melting," Bjork said. Glaciers are shrinking by an average of 25 meters a year, compared to five to six meters about two decades ago, scientists concluded after studying the evolution of glaciers over 130 years using satellite images and 200,000 old photographs. (Reuters)