A combination of climate change and La Niña weather patterns has fueled catastrophic flooding across southern Africa over the past month, killing at least 200 people and affecting hundreds of thousands, according to a study released Thursday.
The report, by World Weather Attribution (WWA), found that the intensity of extreme rainfall events has increased by 40% since preindustrial times, indicating that warmer ocean temperatures linked to greenhouse gas emissions are a contributing factor. Current La Niña conditions further intensified the downpours.
Since December, severe floods have ravaged Mozambique, South Africa, Zimbabwe, and Eswatini, with some areas receiving more than a year’s worth of rain in just a few days. Overflowing rivers forced the closure of South Africa’s Kruger National Park and are expected to cost millions of dollars in repairs.
“Data confirms a clear trend toward heavier, more violent rainfall,” WWA said. “This effect was compounded by the ongoing La Niña, which naturally brings wetter conditions to this region, now occurring in a more moisture-rich atmosphere.”
La Niña, a cyclical phenomenon, involves temporary cooling of the central and eastern Pacific Ocean. The World Meteorological Organization has forecast a weak La Niña for this cycle but warned that climate change–driven warmer sea temperatures are increasing the risk of both floods and droughts.
“Human-caused climate change is supercharging rainfall events like this, with devastating consequences for those in its path,” said Izidine Pinto, co-author and senior climate researcher at the Royal Netherlands Meteorological Institute.
“Our analysis clearly shows that the continued burning of fossil fuels is intensifying extreme rainfall, turning these events into far more severe disasters.”