The world’s food system is coming under mounting pressure from climate change, extreme weather, wars and trade disruptions, with new research warning that shifts in agricultural productivity could increase risks of conflict and displacement — particularly in vulnerable regions such as South Asia and the Sahel.
The Climate-Driven Agricultural Decline Index (CADI), developed by researchers Laura Mayoral and Hannes Mueller, maps how climate change is reshaping agricultural productivity worldwide.
“The heaviest losses are in the tropical regions,” said Mueller, a researcher at the Institute for Economic Analysis and Barcelona School of Economics.
Hundreds of millions of people already live in areas producing less food than 30 years ago. Within 25 years, nearly half the world’s population could live in areas where agricultural productivity has declined.
Droughts and extreme weather are damaging harvests, while wars and geopolitical tensions are disrupting food, fuel and fertiliser supplies.
The Ukraine war has repeatedly unsettled grain markets, while disruption surrounding the Strait of Hormuz has increased fuel and fertiliser costs.
But researchers found that declining production is not the only potential source of conflict.
Rising agricultural productivity can also create tensions by making previously marginal land more valuable.
“If we know that your land is going to become more productive, maybe I want to grab it from you today,” Mueller said.
Large agricultural companies are already buying land expected to become more productive in coming decades, potentially driving up prices and displacing local communities.
The research suggests such agricultural shifts are more likely to fuel violence in non-democratic countries, while democratic institutions can provide mechanisms for competing groups to negotiate over changing access to land and resources.
South Asia is particularly vulnerable, according to Abdullah Fahimi of the German Council on Foreign Relations.
“The regions we should watch most closely are South Asia and the Sahel,” he said, citing the combination of climate vulnerability and rapid population growth.
Home to around two billion people, South Asia depends heavily on vulnerable water systems as well as imported food. At the same time, domestic agriculture faces intensifying heatwaves, floods, declining land productivity and saltwater intrusion.
The Himalayas and Hindu Kush, which provide crucial water for agriculture and drinking across the region, are also undergoing rapid changes as glaciers and snow melt.
In the short term, melting could increase water availability. Later this century, however, Fahimi warned of “a huge humanitarian crisis that could affect around 2 billion people.”
Food insecurity can also drive migration, undermine confidence in governments and create opportunities for armed groups to recruit people whose livelihoods have collapsed.
Researchers stress that climate change and food shortages do not automatically cause violence. The decisive factor may be whether institutions can manage disputes over increasingly scarce -- or newly valuable -- land, water and livelihoods.
Climate adaptation, they argue, therefore cannot be limited to new crops and technologies.
Where institutions cannot peacefully manage the redistribution of resources and opportunities, pressure on the food system could ultimately become pressure on peace itself.
