Climate change could transform East Africa’s Lake Victoria into a dangerous thunderstorm hotspot, threatening some 200,000 fishermen who ply its waters at night, according to a study released Tuesday.
Already some 3,000 to 5,000 fishermen lose their lives in violent storms on the lake every year, according to the International Red Cross.
Superstorms that only occur once every 15 years today would, if global warming continues apace, happen annually by century’s end, said the study published in Nature Communications.
The basic weather pattern that causes night-time storms over Victoria exists already, but would be amplified, explained lead author Wim Thiery, a researcher at the University of Leuven in Belgium.
“During the day, a breeze develops that flows from the cool water towards the warm land,” he said in a statement.
“At night, we see the opposite: the land breeze flows away from the cooling land,” converging over the warmer, oval lake.
“Add evaporation to this cocktail, and you get a lot of storms, rain, wind and waves,” he said.
Thiery and colleagues used NASA satellite data to map the number of hazardous thunderstorms in East Africa — at a resolution of 15-minute intervals — from 2005 to 2013.
To predict the impact of climate change of the lake’s weather patterns, the researchers then ran climate simulations based on the assumption that global warming would continue at its current rate.
Under that scenario, “the extreme amounts of rainfall over Lake Victoria will increase by twice as much as the rainfall over the surrounding land,” creating a hotspot for nocturnal storms, they found.
With a surface of 70,000 square kilometres (27,000 square miles), Lake Victoria is the biggest lake in Africa.