CHILE: Scientist Warns of Threats to Rock Glaciers

  • by Daniela Estrada (santiago)
  • Inter Press Service

An assistant professor of geography at the University of Waterloo in Canada, Brenning spoke with IPS after giving a lecture this week on the little-known rock glaciers to geology students at the University of Chile, who had specially invited him.

The expert drew attention in Chile last year after the results of studies he carried out were reported locally. His research in this country found that three large mining companies were affecting several square kilometres of rock glaciers by building roads and other infrastructure and piling sterile material on them.

Brenning specifically pointed his finger at the Andean Division of the state-run National Copper Corporation (CODELCO), the Los Bronces mine operated by the London-based Anglo American mining giant, and Los Pelambres, a Chilean mining company.

In his lecture Wednesday, Brenning explained that rock glaciers are important natural sources of frozen water that contribute to the availability of water supplies during the southern hemisphere summer. And they are threatened not only by mining operations, but by climate change as well, he said.

Under the top layer of rock, these glaciers are 40 to 60 percent ice, he said.

Because it takes thousands of years for rock glaciers to regenerate, and since they are unstable, moving several centimetres a year, building infrastructure on top of them is not recommendable, said Brenning.

Rock glaciers 'are very difficult to study because they are not as easily identifiable as typical glaciers, which are white,' he told IPS. 'They are hard to detect and it is difficult to monitor their movement. This is a technological challenge for geomatics,' the discipline of gathering, storing, analysing, interpreting, distributing and using geographic information.

Brenning, who combines analysis of satellite images with aerial photos and field work, believes rock glaciers are found mainly in central Chile, and that their total surface area is approximately 500 square kilometres.

According to his research, the three mining companies have affected 3.2 square kilometres of rock glacier, encompassing between 23 and 35 million cubic metres of water, over the last decade, he said, pointing out that part of that area was literally removed.

His research found that CODELCO removed 1.3 square kilometres by 2005, while Anglo American removed some 20 hectares.

Last year, the two companies responded to such reports by repeating once more that they had the necessary environmental permits to operate their mines – an argument that is questioned by Brenning.

Los Pelambres, in the meantime, denied that rock glaciers even existed.

As a result of global warming, South America’s glaciers, which are an important source of meltwater, are in fast retreat.

A new awareness of the need to protect glaciers in Chile has emerged since 2006, when the government of Ricardo Lagos (2000-2006) approved the environmental impact study of the Pascua Lama mine, owned by Canada’s Barrick Gold Corporation, which has been fought tooth and nail by environmentalists and local residents.

Construction of the mine, which straddles the border between Chile and Argentina in the Andes mountains, remains on hold.

The company initially planned to remove three glaciers on the Chilean side, in order to get to the minerals underneath them. But that plan was vetoed by Chilean authorities.

However, the glaciers have already been affected by the prospecting, according to different sources.

This and similar conflicts over mining projects, added to the retreat of glaciers around the world due to climate change, prompted the government to draft a policy for the protection and conservation of glaciers, which was finally approved on Apr. 14.

But some environmental organisations are demanding passage of a stricter law for the protection of glaciers, which remains stalled in parliament.

Although the administration of socialist President Michelle Bachelet argues that the government policy is easier and faster to implement than a law, environmentalists say it was the lobbying carried out by the mining corporations that tipped the balance of political support towards the first option.

While Brenning sees the new policy as 'a step forward,' he takes issue with several aspects. For example, it fails to specifically define what a rock glacier is, he said.

He also complains that it leaves the approval of projects that affect the glaciers in the hands of the environmental impact assessment system, which in his view has shown itself to be inefficient and ineffective in such cases.

He also questions the invocation of the so-called 'higher interests of the nation.'

The policy approved by the government this month says that 'Although the policy states the need to preserve the glaciers, their appropriate management must be considered when the specific needs of the watershed so require, just as eventual interventions will be considered when required by the higher interests of the nation.'

'Perhaps what should be considered is the creation of a policy on land use, to help concentrate these projects in certain areas and keep other areas free of mining,' Brenning suggested.

'It worries me to see projects that in the future could affect areas high up in the mountains where glaciers and rock glaciers are found,' he said.

He also said Chile should focus on awareness-raising and education among geologists, geographers, government officials and the general public, especially regarding rock glaciers, about which there is very little understanding.

'Rock glaciers are a hidden, little-known phenomenon. Even in the scientific world, there is very little literature on them. The Alps have been more closely studied,' said Brenning.

The government policy on glaciers states that so far more than 3,100 glaciers have been identified in Chile, with a total estimated surface area of 20,188 square kilometres. Of that total, more than 15,000 square kilometres are made up of the North and South Patagonian Ice Fields.

The surface area that has not yet been mapped is estimated at 4,700 square kilometres of ice.

The policy also states that the majority of Chilean glaciers are retreating and have experienced losses in surface area and thickness in response to climate change.

'The retreat and thinning detected in Chile in the last 30 years have accelerated, to up to twice as fast in the last 10 years,' it says.

Brenning is currently working on monitoring two rock glaciers located in the mountains around the Chilean capital, using instruments like GPS (global positioning system).

© Inter Press Service (2009) — All Rights ReservedOriginal source: Inter Press Service