Climate change is adversely affecting the production of key crops such as wheat and rice, with some countries faring far worse than others, according to researchers including those of Indian origin.
The world's top 10 crops—barley, cassava, maize, oil palm, rapeseed, rice, sorghum, soybean, sugarcane and wheat—supply a combined 83 per cent of all calories produced on cropland.
Yields have long been projected to decrease in future climate conditions.
The research, published in the journal PLOS ONE, shows that climate change has already affected production of these key energy sources.
Scientists from the University of Oxford in the UK and the University of Copenhagen in Denmark used weather and reported crop data to evaluate the potential impact of observed climate change.
They found that observed climate change causes a significant yield variation in the world's top 10 crops, ranging from a decrease of 13.4 per cent for oil palm to an increase of 3.5 per cent for soybean, and resulting in an average reduction of about one per cent of consumable food calories from these top 10 crops.
"There are winners and losers, and some countries that are already food insecure fare worse," said Deepak Ray of the University of Minnesota in the US.
"These findings indicate which geographical areas and crops are most at risk, making them relevant to those working to achieve the UN Sustainable Development Goals of ending hunger and limiting the effects of climate change. Insights like these lead to new questions and crucial next steps," said Ray.
The impacts of climate change on global food production are mostly negative in Europe, Southern Africa, and Australia, generally positive in Latin America, and mixed in Asia and Northern and Central America.
About half of all food-insecure countries are experiencing decreases in crop production—and so are some affluent industrialised countries in Western Europe, the study found.
In contrast, recent climate change has increased the yields of certain crops in some areas of the upper Midwest US.
"This is a very complex system, so a careful statistical and data science modeling component is crucial to understand the dependencies and cascading effects of small or large changes," said Snigdhansu Chatterjee of University of Minnesota.
The report has implications for major food companies, commodity traders and the countries in which they operate, as well as for citizens worldwide, researchers said.
