Melting glaciers in Latin America's southern Andean range expose the region to risk of future water shortages, new data indicated.

A new study in The Cryosphere journal said climate change caused the glaciers to melt and shrink 30-50 percent since the 1970s and could eventually melt many of them away in coming years.

Peru's glaciers were cited in the study among those severely affected.

The Andean glaciers are a vital source of fresh water for tens of millions of people in the region, who are already affected by huge income disparities, poor housing and sanitation in the less developed areas of South America.

Findings in The Cryosphere, published from Germany, indicated the glaciers melting at their fastest rates in more than 300 years. The study was the most comprehensive investigation of climate change impact on Andean ice.

The role of glaciers as temporal water reservoirs is particularly pronounced in the outer tropics because of the very distinct wet and dry seasons, the study said.

"Rapid glacier retreat caused by climatic changes is thus a major concern, and decision makers demand urgently for regional/local glacier evolution trends, ice mass estimates and runoff assessments."

It said data from the affected area remains very scarce. The Cordillera Vilcanota in southern Peruvian Andes is the second largest glacier in Peru after the Cordillera Blanca.

"While we found only marginal glacier changes between 1962 and 1985, there has been a massive ice loss since 1985 (about 30 percent of area and about 45 percent of volume)."

The study, "Glacier changes and climate trends derived from multiple sources in the data scarce Cordillera Vilcanota region, southern Peruvian Andes" brought together scientists from Peru, France, Switzerland and the United States.

Data on about half of all Andean glaciers in South America showed that ice loss appeared to have been caused by an average temperature increase of 1.26 degrees Fahrenheit over the past 70 years.

Evidence that the glaciers are shrinking at an unprecedented pace led scientists to conclude that smaller glaciers would also be vulnerable, exposing communities downstream to risks of water shortages.

One of the worst affected glaciers, Chacaltaya in the Bolivian Andes, used to be a ski resort before it lost its ice completely. The glacier was believed to be about 18,000 years old and a key source of slow release of water.

Scientists say underground water resources depend on glaciers which, in some parts of the Andes, supply up to 60 percent of fresh water.