Earth Day 2013 is being marked across the world today under the theme, “The Face of Climate Change”. It has been predicted that climate change will, by 2050, have changed the Western Cape’s rainfall pattern, and forecasts show that fynbos is under threat.
Earth Day is the largest secular event in the world – and more people join in every year. On and around Earth Day, people of all ages and backgrounds come together to haul garbage, clean up coral reefs and mountain trails, show movies, sign petitions, march to solve the climate crises, hold town hall meetings to plan a better future, and rally to save endangered species. More than 100-million schoolchildren around the world learn about the importance of clean air and water.
While the province has always been a dry region in South Africa, climate change will make it drier.
Human activity plays a role in climate change, as carbon emissions add to the greenhouse gases that result in high temperatures. The Cableway is mindful of this and works hard to decrease its carbon emissions.
The Cableway has an environmental policy that is strictly adhered to. Resource management includes minimising the use of water and energy and being responsible with waste management.
The Cableway’s responsible tourism programme is built on the three pillars of sustainable development: people, planet and profit. All of these contribute to the reduction of carbon emissions and waste in some way. Huge effort goes into decreasing the company’s ecological footprint and caring for the wide range of flora and fauna that lives and thrives on Table Mountain.
Professor Guy Midgley, head of the Climate Change and BioAdaptation Division at the South African National Botanical Institute, was quoted in the Kirstenbosch National Botanical Garden newsletter recently as saying that one of the critical elements in the evolution of fynbos is the unusually predictable winter rainfall pattern that has been in place for millions of years.
“While we are currently in the stable but very recent Holocene interglacial period, climates up to 5° Celsius cooler have prevailed for 90% of this time. How the fynbos and succulent Karoo biomes will respond in this unusually warm interglacial period superimposed with a warming trend is worrying.”
The Holocene epoch has lasted from about 10 000 years ago to the present day. It covers the period since the ice retreated after the last glaciation, and it is sometimes regarded as just another interglacial period.
The fossil pollen record shows that fynbos has occurred as far north as Namibia during colder climates, but retreats into the refugium of the Cape Fold Belt (the Table Mountain range), and is likely to retreat further, as the climate warms.
Midgley gave some assurance that the Cape Fold Belt is also responsible for limiting extinctions, as migrations up a slope are easy, as the air is cooler as you ascend, which means that the fynbos on Table Mountain will become of increased significance.
“One kilometre in altitude represents a 6° to 8° Celsius shift in temperature. Our species richness is much higher mainly due to these topographical escape routes,” Midgley said.
Dominic Chadbon, the Fynbos Guy, said the Western Cape climate will become hotter, windier and drier during summer, while in winter there will be fewer rain-bearing cold fronts.
“The impact on the fynbos could be huge. Longer, hotter and drier summers will mean more fires and even more pressure on plants and soil in regularly burnt areas like Devil’s Peak. Some super-gloomy estimates put the potential loss at up to 50% of the fynbos biome, but I am never sure how seriously we should take these estimates – the truth is we don’t really know.
“Drier conditions would certainly be a disaster for animal life on these mountains – it’s tough enough already for birds and frogs to survive; throw in hotter summers and dry winters and there is a biodiversity disaster,” Chadbon said.
According to him, it remains to be seen which plants will be most affected by climate change: “I have seen some mention of plant species that already seem to be in retreat – but remember that all fynbos plants are adapted to drought. I once wrote off a huge stand of confetti bushes at the end of summer last year as they appeared to be dying. They are now the most luxuriant bushes on the western side of the mountain.
“The very hardy plants – succulents, for example – may do well; other water/rainfall-dependent species like our early spring bulbs could be wiped out, let alone those pockets of forest on the mountain.”
In short, the fynbos biome is already one that operates in tough environmental conditions; climate change is going to exert more pressure on a finely tuned ecosystem.
An extremely dire prediction comes from University of Cape Town (UCT) researcher Mike Meadows. Interviewed in the Cape Times, Meadows said new research indicates that the drier winters caused by climate change could spell the end for the Cape’s unique fynbos.
Meadows is from the UCT’s Department of Environment and Geographical Science, and part of an international team that did research. He said future drier conditions and the increased risk of fire could put fynbos at risk of extinction.
“These plants are tough and they are already used to dry conditions, but further aridity could make fires more frequent, which could damage the soils and make it even harder for the native plants to survive here.
“Unfortunately, this is their only native habitat, so such a change here might eventually threaten their very existence,” Meadows said.
The team’s findings support what sophisticated climate models have been suggesting would happen in the Cape in the future.