Kilimanjaro ice-field 'will be gone in 20 years'

Many of the world's mountain glaciers will have disappeared within a generation if global warming continues, scientists have warned.</p>A study showed mountain glaciers in tropical regions are most vulnerable and are already showing signs of succumbing to a warmer world, said Lonnie Thompson, professor of geological sciences at Ohio State University.</p>At least one-third of the massive ice-field on Mount Kilimanjaro, Africa's highest mountain, has disappeared in the past two decades and about 80 per cent of it has been lost since it was first mapped in 1912, said Professor Thompson.</p>In Peru, the Quelccaya ice-cap of the southern Andes mountains has shrunk by 20 per cent since 1963. The scientists found that the rate of retreat of one of the main glaciers running out of the ice-cap, the Qori Kalis, was more than 30 times greater in the past three years than it was between the years 1963 and 1978.</p>The melting ice from the glacier has formed a large lake which did not exist in 1983 but now covers an area of about 10 acres, four acres bigger than in 1998. Bare earth has been exposed for the first time in thousands of years.</p>Professor Thompson presented the latest findings from two decades of studies by his research team, who surveyed tropical ice-caps and ice-cores from South America, Africa, China and Tibet, at the annual meeting of the American Association for the Advancement of Science in San Francisco.</p>By analysing the isotopes of oxygen in the ice, the scientists can estimate the temperature of the climate at the time the snow fell. From this they discovered that for the ice-cores of the Tibetan plateau the past 50 years have been the warmest in the history of the ice-cap.</p>Professor Thompson said: "We have long predicted that the first signs of changes caused by global warming would appear at the few fragile, high-altitude ice-caps and glaciers in the tropics. These findings confirm those predictions."</p>The melting glaciers are not only an ecological catastrophe, they also threaten local economies. About four-fifths of the ice-cap on Kilimanjaro has disappeared over the past 80 years, jeopardising the tourist trade. "At this rate, all of the ice will be gone between the years 2010 and 2020, said Professor Thompson. "And that's probably a conservative estimate."</p>The melting of the Quelccaya ice-cap of Peru will be even more devastating. "The loss of these frozen reservoirs threaten water resources for hydroelectric power production in the region, and for crop irrigation and municipal water supplies," the professor said. "What we're doing is cashing in on a bank account that was built over thousands of years but isn't being replenished. Once it's gone, it will be difficult to reform."</p>