BOGOTA (AlertNet) - Colombia's glaciers are melting so fast that within 25 years they are all expected to disappear, a leading government environmental official has said.

Glacier retreat in the Andean nation, caused by rising temperatures, is a growing concern as modelling and data collected from satellite imagery and weather stations show that Colombia's glaciers are consistently shrinking at an accelerating rate.

"There's been a sharp downward trend in snow coverage of several of Colombia's big glaciers particularly since 1985. If current rates continue, Colombia won't have any glaciers left by 2035," said Ricardo Lozano, head of the Colombian Institute of Hydrology, Meteorology and Environmental Studies (IDEAM).

Lozano, speaking at a conference on climate change in Bogota on Monday, added that "there's a 90 percent probability that the predictions are correct".

El Cocuy national park in northeast Colombia has the highest concentration of glacial peaks in the country. Today, three of the park's 25 glaciers have no snow covering them.

"In 1960, there was 37 km of snow covering El Cocuy's glaciers. Today that figure is around 22 km," said Lozano.

Snow and ice melting from glaciers feed rivers with water, providing people with a key source of water for drinking and farming.

Across Andean capitals, such as in Ecuador's Quito and Bolivia's La Paz, glacier recession has become a critical issue as millions of people rely on the shrinking glaciers surrounding these cities to provide them with water.

Colombia is home to a unique alpine grassland ecosystem known as "paramos", which acts like a giant sponge regulating water flows from glaciers. This highland ecosystem, say Colombian scientists, is particularly vulnerable to the effects of climate changes, including rising temperatures, changes in rainfall patterns and declining water run-offs from glaciers.

"If the current situation continues, 56 percent of Colombia's paramos will disappear by 2050, while 25 percent of the Colombian population depends on water resources from these paramos," said Lozano.

"It's a water supply issue and conserving this ecosystem is a priority," he added.

Colombia, like most countries in South America, is experiencing the effects of climate change, such as increases in flooding, droughts, desertification and rising sea levels.

Local scientists say nearly 20 percent of Colombia's small island of San Andres, off the country's Caribbean coast, is at risk of being washed away by rising sea levels by 2050.

Lozano said a key priority in Colombia is to tackle the spread of tropical diseases made worse by global warming.

"We'll see an increase in dengue and malaria outbreaks brought on by climate change in Colombia," he said.

Warmer temperatures and heavier rainfall in certain areas are providing optimal breeding conditions for mosquitoes, which transmit diseases such as dengue and malaria. Immense lagoons created by more frequent torrential rains and storms allow mosquitoes to reproduce more and spread into new regions.

The Colombian government is spending up to 0.24 percent of its gross domestic product (GDP) on adapting to climate change and its effects.

Colombia will be sending a small delegation to the Copenhagen summit on climate change in December, where it will be expected to urge industrialised nations to provide more funds and technology to help developing countries tackle climate change.

"We must learn how to calculate the cost of climate change better," said Lozano, "and ask ourselves what it would really cost us if we did nothing about it."

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