Andean glaciers are melting so fast that some are expected to disappear within 15-25 years, denying major cities water supplies and putting populations and food supplies at risk in Colombia, Peru, Chile, Venezuela, Ecuador, Argentina and Bolivia.
The Chacaltaya glacier in Bolivia, the source of fresh water for the cities of La Paz and El Alto, is expected to completely melt within 15 years if present trends continue. Mount Huascaran, Peru's most famous mountain, has lost 1,280 hectares of ice, around 40 percent of the area it covered only 30 years ago. The O'Higgins glacier in Chile has shrunk by 14.5km in 100 years and Argentina's Upsala glacier is losing 14m a year.
Although a few glaciers in southern Patagonia are increasing in size, almost all near the tropics are in rapid retreat. Some glaciers in Colombia are now less than 20 percent of the mass recorded in 1850, and Ecuador could lose half its most important glaciers within 20 years.
The rate of glacier retreat has shocked scientists, says a report on the effects of global warming in Latin America by 20 UK-based environment and development groups who have drawn on national scientific assessments. Their study says climate change is accelerating the deglaciation phenomenon.
"The speeding up of the ... process is a catastrophic danger," says Carmen Felipe, president of Peru's water management institute.
In the short term, Felipe says, it could cause overflows of reservoirs and trigger mudslides, and in the longer term cut water supplies.
According to the Colombian institute of hydrology, back in 1983 the five major glaciers in El Cocuy national park were expected to last at least 300 years, but measurements taken last year suggest that they may all disappear within 25 years. Meanwhile, the ice sheet on the Ecuadorian volcano Cotopaxi and its glacier has shrunk by 30 percent since 1976.
"The [drastic melt] forces people to farm at higher altitudes to grow their crops, adding to deforestation, which in turn undermines water sources and leads to soil erosion and putting the survival of Andean cultures at risk," says the report by the Working Group on Climate Change and Development, which includes the International Institute for Environment and Development, Christian Aid, Cafod, WWF, Greenpeace and Progressio.
Their report, Up in Smoke, says snow and rainfall patterns in South America and the Caribbean are becoming less predictable and more extreme.
Rises in sea level are expected to be especially severe in the region over the next 50 years, with 60 of Latin America's 77 largest cities located on the coast. The first hurricanes have recently hit south of the equator line in Brazil.
"The net effect ... is to reduce the capacity of natural ecosystems to act as buffers against extreme weather,"it says.
"What we are seeing are many more negative and cumulative impacts. The larger the rate of [climate] change, the more the adverse effects predominate. Climate change is set to turn an already rough ride into an impossible one," says the report, which adds that the impact of climate change is "hugely" magnified by existing environmental abuse.
Yesterday, the groups called on rich countries to urgently reduce greenhouse gas emissions and proposed that Latin America and the Caribbean governments be helped to reduce their vulnerability to extreme weather.