UC BERKELEY/STANFORD/NYU (US)—Climate change could increase the likelihood of civil war in sub-Saharan Africa by more than 50 percent within the next two decades.
A new study says the findings make it even more urgent that African governments and foreign aid donors accelerate support of new and/or expanded policies to assist with African adaptation to climate change.
Findings by a team at University of California, Berkeley, Stanford University, New York University, and Harvard University was published in the journal Proceedings of the National Academy of Sciences (PNAS).
The study provides the first quantitative evidence linking climate change and the risk of civil conflict.
“Despite recent high-level statements suggesting that climate change could worsen the risk of civil conflict, until now we had little quantitative evidence linking the two,” says Marshall Burke, the study’s lead author and a graduate student at UC Berkeley’s Department of Agricultural and Resource Economics.
“Unfortunately, our study finds that climate change could increase the risk of African civil war by over 50 percent in 2030 relative to 1990, with huge potential costs to human livelihoods.”
Understanding the causes and consequences of civil strife in much of the African continent has been a major focus of the social sciences for decades, as monumental suffering has resulted from it, says Edward Miguel, professor of economics at UC Berkeley and faculty director of UC Berkeley’s Center for Evaluation for Global Action.
In the case of the Democratic Republic of Congo’s, the International Rescue Committee estimates that at least 5.4 million people have died from fighting, hunger, and disease during that country’s ongoing civil unrest over the past 10 years.
“We were definitely surprised that the linkages between temperature and recent conflict were so strong,” says Miguel.
“But the result makes sense. The large majority of the poor in most African countries depend on agriculture for their livelihoods, and their crops are quite sensitive to small changes in temperature. So when temperatures rise, the livelihoods of many in Africa suffer greatly, and the disadvantaged become more likely to take up arms.”
In the study, the researchers first combined historical data on civil wars in sub-Saharan Africa with rainfall and temperature records across the continent.
They found that between 1980 and 2002, civil wars were significantly more likely in warmer-than-average years, with a 1 degree Celsius increase in temperature in a given year raising the incidence of conflict across the continent by nearly 50 percent.
Building on this historical relationship between temperature and conflict, the researchers then used projections of future temperature and precipitation change to quantify future changes in the likelihood of African civil war.
Based on climate projections from 20 global climate models, the researchers found that the incidence of African civil war could increase 55 percent by 2030, resulting in an additional 390,000 battle deaths if future wars are as deadly as recent ones.
All climate models project rising temperatures in coming decades, says David Lobell, study coauthor and an assistant professor of environmental earth systems science at Stanford.
“On average, the models suggest that temperatures over the African continent will increase by a little over 1 degree Celsius by 2030,” he adds. “Given the strong historical relationship between temperature rise and conflict, this expected future rise in temperature is enough to cause big increases in the likelihood of conflict.”
To confirm that this projection was not the result of large effects in just a few countries or due to overreliance on a particular climate model, the researchers recalculated future conflict projections using alternate data.
“No matter what we tried—different historical climate data, different climate model projections, different subsets of the conflict data—we still found the same basic result,” explains Lobell.
It’s easy to think of climate change as a long way off, the researchers say, but their study shows how sensitive many human systems are to small increases in temperature, and how fast the negative impacts of climate change could be felt.
“Our findings provide strong impetus to ramp up investments in African adaptation to climate change by such steps as developing crop varieties less sensitive to extreme heat and promoting insurance plans to help protect farmers from adverse effects of the hotter climate,” says Burke.
Applying findings from this study could prove useful to policy makers at the upcoming Copenhagen negotiations in December in determining both the speed and magnitude of response to climate change, the authors maintain.
“If the sub-Saharan climate continues to warm and little is done to help its countries better adapt to high temperatures, the human costs are likely to be staggering,” predicts Burke.
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