Gill Moodie
A giant iceberg that has been lurking in the southern ocean for 12 years is making its way north from Antarctica, firing scientists’ dreams of mining icebergs for freshwater.
Bigger than the Cape Peninsula, the iceberg known as Atlantic 22B, was formed in September 1986 when a massive piece of ice broke off from the Filchner ice shelf and formed three icebergs that became trapped in shallow waters.
Now Atlantic 22B has broken free and is fuelling the imaginations of scientists such as Henry Valentine, an oceanographer with the Department of Environment Affairs, who says mining icebergs is not science fiction. In the 1980s French scientists did a feasibility study of towing icebergs to the Persian Gulf for Saudi Arabia.
It was established that an iceberg of 1km2 would survive the journey to the region and would be cheaper than desalinating seawater. But the scheme was dropped because there were no tugs powerful enough to pull such a dangerous object, particularly as ocean currents would complicate the procedure.
Valentine says South Africa’s West Coast would be perfect for mooring icebergs as the continental shelf’s slope is relatively gentle. The chief obstacle in this country is cost.
The source of the excitement is rare because of its sheer size: 56km long and 19km wide. Surrounded by pack ice, Atlantic 22B is moving north at an estimated 5km a day. It is highly likely that it will break up but, should some pieces reach South Africa’s West Coast in a projected five years time, they will affect the Western Cape’s rainfall and wind patterns.
It would not be the first time for a “berg” to skim our coast: in 1896 an iceberg was spotted 80km off Cape Agulhas.
Atlantic 22B is the second of its family to venture from Antarctic waters. In 1991 Atlantic 24A broke free and headed north, carrying a polar climate, penguins, albatrosses and Argentina’s abandoned Antarctic base. It ran into storms near the Falkland Islands, breaking up into small icebergs which reached the coast of Buenos Aires.
Atlantic 22B may well end up off the coast of Brazil depending on the currents, but it is a floating reminder to scientists that South Africa may have to be more imaginative about water sources in the future.
Atlantic 22B also serves as a sign that global warming may be causing Antarctica to shrink, which could lead to a rise of sea level. Ice shelves such as that of Filchner form the edges of the ice sheets that make up the continental land mass.
Though scientists do not agree on whether the purpose of ice shelves is to protect land-ice from the ocean, there have been five known cases of shelf disintegration in the past 50 years which, say some researchers, coincides with a rise 2,5C in the regional climate since the 1940s.
With environmentalists becoming concerned about Earth’s freshwater resources, it is tantalising that Antarctica sheds over two trillion metric tonnes of ice a year.
The continent contains 70% of the world’s freshwater and 90% of its ice. Most Antarctic scientific stations rely on melted ice for their water requirements – the continent’s isolation has kept its ice the most pollution-free in the world.
Dr Vladimir Smakhtin, a hydrologist at Rhodes University’s Institute for Water Research, says South Africa is very well situated for exploiting icebergs as they would be towed through generally cold waters.
Tami Sokutu, deputy director general for policy at the Department of Water Affairs, chuckled at the prospect of iceberg mining. Such ambitious schemes are simply beyond the country’s means. With predictions that South Africa could run out of water between 2025 and 2030, the department prefers to focus on its own backyard: managing surface and ground water as efficiently as possible.
The national water Bill, passed this month by Parliament, is part of the department’s strategy to become more actively involved with water supply.
The Bill ends private ownership of water and introduces water licences which will be temporary and subject to review. Authorities will be able to enter private and commercial properties and monitor how much water is being used.
The thinking behind the Bill is that by making users such as farmers, foresters and industry pay for excessive use, it will become cost- effective for them to use water more efficiently.
The Bill has already run into opposition, with the National Party and Inkatha Freedom Party threatening to challenge the legislation in the Constitutional Court. Some critics charge that it is a form of nationalisation.
Other projects by the Department of Water Affairs and Forestry include the removal of water-guzzling alien plants from catchment areas down to the smaller-scale Waterwise Project. The Waterwise Project, which was started in the Western Cape, aims to raise awareness that the watering of gardens is the biggest water waster in the suburbs. Planting indigenous species cuts consumption considerably as they survive with less water than European plants.
Sokutu says this is a small project but it goes a long way. Ideally, the department would like to supply indigenous plants for free to gardeners but there is not enough money available.
The most important message to get across, says Sokutu, is that water is a “finite resource. People should use water as if there is not enough.”
But, as the country’s water becomes scarcer, proposals for iceberg mining – and even selling “berg” water on to economically rich, water-poor states – may seem more viable.