As forests are cleared for cropland, the loss of natural cooling mechanisms could cause heatwaves in parts of Africa to last 12 times longer by 2100, creating "near-perennial" heat states.
The Problem We Set Out to Solve
Africa is in a heat crisis. But here is what makes it unfair: Africa contributes almost nothing to global warming, yet it is suffering the worst effects. The continent has less than 4% of global carbon emissions, but it faces some of the most intense heatwaves on Earth. Scientists have known the facts for years. But what we did not fully understand was how much of Africa's heat problem comes from global warming and how much comes from things happening within Africa itself? This is the question we aimed to address. Our latest study, Coupled climate–land-use interactions modulate projected heatwave intensification across Africa, which was published in Communications Earth & Environment, looks at how heatwaves are becoming more dangerous in Africa.
These future projections reveal a major departure from historical variability, particularly in the late 21st century. We project substantial increases in the frequency, duration, and number of heatwaves (HWF, HWD, and HWN) across Africa.
The Discovery: Land Use Matters More Than We Thought
When we started this research, we knew that cutting down forests and converting grasslands to farms could affect local temperatures. However, we were unaware of the extent of the impact. We did not have numbers. We did not know whether it was a small effect or a big one. So we built computer models. We tested them against real-world data from Africa. And then we used artificial intelligence to break down exactly which factors drive heat waves. The results surprised us. Temperature and humidity together account for more than one-third of the increase in deadly heatwaves in some African regions. And this effect gets worse, much worse, when natural land is converted to farms and pastures. This was the key insight: the way we use land is not separate from climate change. It is part of it. It amplifies it.
What This Means: The Impossible Choice
This finding reveals a painful truth. In many parts of Africa, people are clearing forests and converting grasslands to farms because they need to feed their families. They need to reduce poverty. These are good reasons. But in doing so, they are making the heat worse. It is not that people are doing anything wrong. They are facing an impossible choice: develop the land to survive or protect it to stay cool. And right now, they are not getting the information they need to make smart choices about this trade-off.
How We Did It: Better Tools for Africa
One reason Africa's heat crisis has been challenging to understand is that global computer models are not very effective at predicting what will happen in Africa. They operate at too coarse a scale. They miss important details. So, we improved the tools. We took 10 different computer models and corrected their errors using real-world data from Africa. This made them much more accurate. We reduced the error in predicting heatwave duration from 1-9 days down to just 0-3 days. That is a tremendous improvement. Then we used artificial intelligence (AI) to look inside these models and understand what is driving the results. Which factors matter most? How do they interact? How much does land use matter compared to global warming? The AI showed us the answer: land use matters a lot.
Why This Research Is Different
A lot of climate research focuses on global emissions. That is important. But this research zooms in on Africa and asks, what can Africans do about this? The answer is more than we thought. Land management decisions matter. How we farm, how we develop cities, and how we protect forests—these choices affect the future heat of African communities. This does not mean Africa can solve the heat crisis on its own. Global emissions still matter. But it does mean Africa has some agency. It has some control.
The dominant land use in Africa has undergone changes from historical times to the future, depending on various emission scenarios.
The Hope in the Numbers
Our research indicates that a moderate reduction in global emissions could significantly lessen heatwaves in West Africa. That is hope. That is a reason to act. And if African countries make smart choices about land use, protecting forests, managing farms in ways that keep the land cooler, and planning cities carefully, they can reduce heat waves even more. The future is not fixed. It depends on choices we make today.
What We Hope Happens Next
We hope this research helps African leaders make better decisions about land use and climate. We hope it helps farmers understand how their choices affect their own future heat. We hope it helps the world understand that Africa's heat crisis is not just something that is happening to Africa; it is something that Africa can help solve. Most of all, we hope this research helps shift the conversation. Instead of asking, "How do we help Africa adapt to climate change?" we should be asking, "How do we help Africa build a cooler, more resilient future through smart choices about land, farming, and development?" The answer to that question starts with understanding the connection between land use and heat. And that is what this research provides.
Lead Authors
Dr. Oluwafemi E. Adeyeri, ARC Centre of Excellence for the Weather of the 21st Century, Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, 2600, Australia.
Dr. Christopher E. Ndehedehe, Australian Rivers Institute, Griffith University, Nathan, QLD 4111, Australia. School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia.