The navel of Africa

You could translate “Inkaba yeAfrica” as the Navel of Africa. Geoscientists Professor Dr. Maarten de Wit from the University of Cape Town in South Africa and Professor Dr. Brian Horsfield from the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences are coordinating this mammoth international project that combines basic research on the Earth System with applied research of relevance to human habitat and activity in the south of the continent. “Africa’sNavel” also alludes to the cradle of humanity which lies in Africa.

“The scientists recognise this area of the world as a prime example of modern Earth System research,” explains GFZ researcher Dr. Robert Trumbull, who is also contributing to the project. For example, the Intergovernmental Panel on Climate Change (IPCC) declares southern Africa to be one of the main areas where climate change will have a very strong impact. A major research organisation such as the Helmholtz Association is ideally equipped for collaborating with African partners to understand this complex system, from the fundamental processes in the ocean and atmosphere through to the effects on human habitat and activity.

The Alfred Wegener Institute in Bremerhaven, for example, is studying how the ocean currents interact around southern Africa. For instance, the Benguela Current transports cold water from the Antarctic northwards along Africa’s Atlantic coast. The cool water prevents practically all the rain from reaching inland areas. On the other side of the continent, the Agulhas Current not only brings tropical warmth from the Equatorial region southwards along the Pacific Coast, but it also sends rainfall to southern Africa. Climate changes influence these ocean currents as well as the rainfall. When GFZ researchers in South Africa analysed the deposits and sediments in the circular Tswaing crater lake, with its 1,130 metres in diameter, they were able to read the climate record of the last 200,000 years and hence the two last major glacial cycles on Earth in this region.

The Tswaing archive indicates that temperatures in South Africa were seven or eight degrees colder when enormous masses of ice buried Earth’s northern hemisphere under it, including the areas where the cities of Berlin and Hamburg are located today. When the climate at Tswaing warmed up again, it also became dryer. This is why water could then be in even shorter in supply in southern Africa, if climate change causes the temperatures to rise. Water is already a rare commodity in South Africa, because the ocean currents in the Atlantic and Indian Oceans prevent much rain from falling in the southern regions of the continent.

Many users are already competing for the water. People not only need drinking water, but also water for washing, for flushing toilets, for irrigating fields and for the livestock. Industry, too, consumes large volumes for manufacturing trucks and cars, machines, steel and fertilisers. And a great deal of water is needed for mining, South Africa’s most important industry. South African miners not only mine coal, but also extract the world’s greatest volumes of gold and platinum, chromium and diamonds from out of the ground. The downsides to mining include the high water and energy consumption and the enormous tailings dumps full of toxic substances.

In one of more than 20 projects, Inkaba yeAfrica studies mineral resources from genesis to disposal. How did the platinum deposits and coal seams develop, how are they used, what consequences does this have for the environment, and what changes might be conceivable? “In answering these questions, Inkaba yeAfrica not only considers mineral resources, but also extends from pure basic research through to engineering and technology in its projects,” explains Trumbull. Inkabe yeAfrica delivers the results and the data basis needed for making political decisions on how business and industry, farmers and private households should prepare for climate change. Which cereal crops will still flourish in more arid or hotter areas? And how much water can probably be expected to be available in 20 years’ time for households, farming, mining or industry?