Floods, drought and pestilence are the stuff of Biblical stories, but if carbon emissions continue, they could be the legacy we leave the next generation.
There is growing agreement among scientists and activists that it may already be too late to prevent a global average temperature rise of 4°C over the next 100-odd years.
Says climate advisor to Oxfam in Southern Africa, Hugh Cole: ”A 4°C increase is the substance of nightmares but unfortunately it is entirely possible.”
What does this mean for Southern Africa? The Met Office Hadley Centre, the UK’s foremost climate-change research centre, says a 4°C rise would mean more forest fires, droughts that occur twice as frequently as they do now, smaller yields of maize and wheat crops, and greater water scarcity in the region.
Guy Midgley, chief specialist scientist at the South African Biodiversity Institute, said that thanks to the global average temperatures rising higher over land surfaces than over oceans, Southern African countries are more likely to experience a 5° or 6° rise, with the peaks centred over Botswana and radiating out to neighbouring countries. The effects of such an increase would worsen by degrees.
Peter Johnston, a researcher specialising in agriculture and water at the Climate Systems Analysis Group at the University of Cape Town, is blunt about Southern Africa’s prospects.
”There should be no wheat left.”
He goes on: maize yields will take a loss in areas that are currently marginal, the climate will be less conducive to deciduous fruit farming, woodlands will advance on the savannah and grazing lands will be overrun by trees. There will be more frequent outbreaks of pests, flooding will increase in the east, temperatures will rise and the soil will dry out.
It may seem like the end of the world but Johnston rejects the idea of a ”day after tomorrow” scenario.
”There’s no end of the world but there will be a serious impact on human life,” he said. ”We have to get used to the fact that things are going to be changing.”
Rainfall patterns destabilised
According to the South African Weather service, rainfall patterns are now officially destabilised.
Summer rainfall has increased in the eastern parts of the country while winter rainfall has decreased in the western regions. This has led to:
- Water shortages in the Western Cape. ”We are getting through summer by the skin of our teeth,†says Stephen Law, director of the Environmental Monitoring Group.
- Small crop yields for farmers with knowledge of farming in more predictable climate conditions.
There has also been an increase in the average minimum and maximum temperatures, which has led to:
- The temperature of the Orange River in Gauteng rising by 2°C, causing 2% more water loss through evaporation. ‘This means there is less water to convert into irrigation, food and economic capacity,†says Professor Anthony Turton of the University of the Free State’s Centre for Environmental Management.
- A lack of winter chilling, causing less favourable conditions for the export of fruit.
- An increase in wildfires in the Western Cape due to drier conditions.