Devastating floods in Nigeria were 80 times more likely because of climate crisis
The heavy rain behind recent devastating flooding in Nigeria, Niger and Chad was made about 80 times more likely by the climate crisis, a study has found.
The finding is the latest stark example of the severe impacts that global heating is already wreaking on communities, even with just a 1C rise in global temperature to date. It adds pressure on the world’s nations at the UN Cop27 climate summit in Egypt to deliver meaningful action on protecting and compensating affected countries.
The floods that struck between June and November were among the deadliest on record in the region. Hundreds of people were killed, 1.5 million were displaced and more than 500,000 hectares of farmland was damaged.
The study, by an international team of climate scientists as part of the World Weather Attribution (WWA) group, used weather data and computer models to compare the likelihood of the heavy rain in today’s heated world versus a world without global heating. Such rain would have been extremely rare without human-caused heating, they found, but is now expected once a decade.
A critical issue for success at Cop27 is establishing funding for “loss and damage” – compensation to rebuild after the unavoidable climate catastrophes that are increasingly hitting vulnerable developing nations, which did little to cause the climate crisis. These countries are demanding action from rich nations.
The WWA study said the reason the floods were so disastrous was that people in the region were already very vulnerable to extreme weather, as a result of poverty, violent conflicts and political instability.
“The analysis found a very clear fingerprint of anthropogenic climate change,” said Prof Maarten van Aalst, the director of the Red Cross Red Crescent Climate Centre, who is at Cop27. “The floods resulted in massive suffering and damages, especially in the context of high human vulnerability.
“As scientists, we’re not in a position to tell Cop27 negotiators whether it needs to be a loss and damage fund, or a facility, or a mosaic of solutions, as are all being discussed,” he said. “But what is very clear from the science is that this is a real and present problem and that it’s particularly the poorest countries that are getting hit very hard, so it’s clear that solutions are needed.”
Prof Johan Rockström, the director of the Potsdam Institute for Climate Impact Research and also at Cop27, said analyses like those from the WWA clearly showed the link between global heating and climate disasters: “So the legitimacy of loss and damage has never been as high as today.”
The WWA team also assessed the 2021 drought in the central Sahel region in Africa that damaged crops and contributed to a food crisis in 2022. However, the scientists were unable to estimate the influence of the climate crisis because of a lack of weather station data, pointing to the need for investment in weather stations.
“We are seeing everywhere in the world just how important it is to know what the weather is today, so we can properly understand how it’s changing and where we need to focus our adaptation efforts,” said Dr Friederike Otto at Imperial College London.
A recent Guardian analysis of hundreds of studies laid bare the devastating intensification of extreme weather that is causing people across the world to lose their lives and livelihoods. At least a dozen major events, from killer heatwaves to broiling seas, would have been all but impossible without human-caused global heating.
Severe events in 2022 include the calamitous flooding in Pakistan, where global heating increased the intensity of rain by about 50%, and the record summer drought across the northern hemisphere, which would have been expected only once every four centuries without the climate crisis. A deadly south Asian heatwave earlier in the year was made 30 times more likely.
The WWA analysis focused on two regions: the Lake Chad basin, where the wet season saw above-average rainfall, and the lower Niger basin, where there were shorter, more intense downpours. The study team included researchers from Nigeria, Cameroon, South Africa, Europe and the US.