Droughts increase to every 15 years, not 50
Research shows climate change poses serious threats for Africa
DROUGHTS can be expected every 15 years and not every 50 years as previously predicted, according to a new UCT study.
Researchers have found that the recent drought, which left dams like the Theewaterskloof empty and saw the City of Cape Town’s taps almost run dry, can now be expected every 15 years.
The 2015 to 2017 drought in the Western Cape was seen as the worst in more than 100 years.
The findings are part of the African Climate and Development Initiative, which aims to quantify the long-term effects of humans on global warming.
Professor Mark New, co-leader of the international, multidisciplinary research team, said the research was aimed not only at reducing future risk, but enhancing on-the-ground responses to reduce the impact on populations of the global south.
“Climate change poses serious development challenges for Africa, from both the greenhouse gas emissions reduction and adaptation to climate risk perspectives. For climate adaptation, African countries are among the most vulnerable to climate change and variability,” he noted.
The recent droughts in Southern Africa served as a stark reminder of the region’s susceptibility to the effects of climate change, according to New.
“This cutting-edge, joint-attribution research enables us to move from just looking at weather risk to a more integrated understanding.”
He said this field of science determined how human influence on the global climate system – global warming – was changing the intensity and frequency of weather extremes.
“This is science led by African researchers, for African application.
“Both the frequency and severity of climate-induced disasters are changing, often for the worse. For the Western Cape, the extent, duration and seasonal distribution of rainfall seem to be changing. Along with higher temperature levels and more evaporation, the implications of drought and climate change for river flows and long-term assurance of water supply are potentially serious.”
New added that this was part of the new normal that people had to start getting used to in a warmer and drier world.
“Even in the best-case scenario, the Western Cape – like the rest of South Africa – is expected to become more vulnerable to food and water insecurity in coming decades. This ups the urgency of implementing the best and most cost-effective adaptation plans in order to increase local resilience.
“In theory, the Western Cape’s water resource system should be reliable 49 out of every 50 years, but its designers did not completely consider the changing climate risk profiles – potentially an adaptation blind spot.”