CLIMATEWIRE | A blistering heat wave in West Africa that sent temperatures soaring over 110 degrees Fahrenheit earlier this month would not have been possible without climate change.
That’s according to new research by the science consortium World Weather Attribution, which investigates the links between global warming and extreme weather events worldwide. Using a combination of historical weather data and computer models, the organization can compare real-life events to hypothetical scenarios in which climate change doesn't exist to determine how much worse they were made by human emissions of greenhouse gases.
The study released Thursday examined a deadly heat wave that swept through parts of West Africa and the continent’s western Sahel region in late March and early April. Temperatures in parts of Burkina Faso reached 113 F, while the city of Kayes in Mali recorded an eye-watering high of 119 F. According to weather historian Maximiliano Herrera, who tracks record-breaking temperatures around the world, it was the hottest April temperature ever recorded on the continent of Africa.
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Extreme heat also scorched parts of Niger, Nigeria, Benin, Togo, Ghana, Ivory Coast, Mauritania, Senegal, Gambia, Guinea-Bissau and Guinea.
The exact number of heat-related illnesses and deaths is still unknown, although millions of people were affected by the extreme temperatures. In Mali, the Gabriel Touré hospital in the city of Bamako reported more than 100 deaths in a matter of days.
West Africa is home to vulnerable populations who lack reliable access to electricity, cooling devices or clean drinking water. Much of the region has also experienced intense urbanization in recent years, reducing green spaces or shade and raising local temperatures in a phenomenon known as the urban heat island effect.
The risk to many people was likely intensified by the extreme temperatures. The heat wave coincided with the holy month of Ramadan, when many Muslims abstain from eating or drinking between dawn and sunset, a practice that may make some people more vulnerable to the health risks posed by extreme heat.
Some of the worst-hit nations, including Burkina Faso and Mali, have also been grappling with frequent power outages because of aging electricity infrastructure, growing demand and additional strain on the electrical grid. Power outages also coincided with the recent heat wave in both countries, reducing access to air conditioning.
“This is a sort of chicken-and-egg relationship,” said Kiswendsida Guigma, a Burkina Faso-based climate scientist with the Red Cross Red Crescent Climate Centre and co-author of the new study, at a press conference announcing the findings. “Because it may also be the case that the heat wave has driven the power cuts, and the power cuts exacerbated the impact of the extreme heat in the area.”
The new analysis found that such extreme heat should only be expected to occur about once every 30 years. In Burkina Faso and Mali, the two hardest-hit countries, the event was even more extraordinary — such temperatures would be expected only about once every 200 years.
The event would have been significantly less severe without the influence of global warming, the study also found. In a world without human-caused climate change, the same kind of heat wave would have been about 1.5 degrees cooler.
In fact, the study found, the extreme temperatures associated with the recent event would not have been possible at all without the influence of human-caused global warming.
This level of heat is exceptional today, but it will become more common as the planet continues to warm. Global temperatures have already risen by about 1.2 degrees Celsius, and heat waves are likely to intensify dramatically with just a few more fractions of a degree.
“At 2 degrees of warming, events like this heat wave are expected to occur about 10 times more frequently,” said Clair Barnes, a research associate at Imperial College London and a co-author of the new study.
That means events featuring these kinds of temperatures are “something to be prepared to adapt to,” she added.
Large swaths of West Africa have already contended with early extremes this season. Dangerously humid heat swept through the region’s southern coastal zone in February, including parts of Nigeria, Benin, Togo, Ghana and Ivory Coast. The heat wave coincided with the Africa Cup of Nations soccer tournament in Ivory Coast, prompting officials to add extra cooling breaks for players to rest and hydrate.
The average heat index, a measure of what the ambient temperature feels like to the human body, rose to around 122 F throughout the area. And it reached a staggering 140 F in some locations, posing extreme dangers to human health.
These temperatures would have been record-breakers even in March or April, when the region’s humid heat highs typically hit their annual peaks. They were even more remarkable for February.
An earlier WWA analysis found that climate change probably made these extreme levels of humid heat about 10 times more likely to occur. And the temperatures themselves were likely about 7 degrees Fahrenheit hotter than they would have been in a world without global warming.
The heat was made even more dangerous because it occurred so early in the season, said Wasiu Adeniyi Ibrahim, head of the Nigerian Meteorological Agency and a co-author of the WWA analysis.
“Many, many people wouldn’t have been acclimatized to the heat,” he said. “It is clear climate change is bringing more and more dangerous hot days to West Africa. With every fraction of a degree of warming, heat waves like the one we experienced in February this year would become even hotter.”
Meanwhile, parts of East Africa have also sizzled this spring. Authorities in South Sudan shuttered schools for two weeks in March as a punishing heat wave set in, sending temperatures soaring as high as 113 F.
Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2024. E&E News provides essential news for energy and environment professionals.