Climate change is already affecting global food production—unequally

Climate change is already affecting global food production -- unequally
Global map of changes in wheat yield on average annually. Units are measured by tons per hectare per year. Credit: Deepak Ray.

The world's top 10 crops— barley, cassava, maize, oil palm, rapeseed, rice, sorghum, soybean, sugarcane and wheat—supply a combined 83 percent of all calories produced on cropland. Yields have long been projected to decrease in future climate conditions. Now, new research shows climate change has already affected production of these key energy sources—and some regions and countries are faring far worse than others.

Published in PLOS ONE, the University of Minnesota-led study, conducted with researchers from the University of Oxford and the University of Copenhagen, used weather and reported crop data to evaluate the potential impact of observed change. The researchers found that:

  • observed climate change causes a significant yield variation in the world's top 10 crops, ranging from a decrease of 13.4 percent for oil palm to an increase of 3.5 percent for soybean, and resulting in an average reduction of approximately one percent (-3.5 X 10e13 kcal/year) of consumable food calories from these top 10 crops;
  • impacts of climate change on are mostly negative in Europe, Southern Africa, and Australia, generally positive in Latin America, and mixed in Asia and Northern and Central America;
  • half of all food-insecure countries are experiencing decreases in crop production—and so are some affluent industrialized countries in Western Europe;
  • contrastingly, recent climate change has increased the yields of certain crops in some areas of the upper Midwest United States.

"There are winners and losers, and some countries that are already food insecure fare worse," says lead author Deepak Ray of the University of Minnesota's Institute on the Environment, whose high-resolution global crop statistics databases have also been used to help to identify how global changes over time. These findings indicate which geographical areas and are most at risk, making them relevant to those working to achieve the U.N. Sustainable Development Goals of ending hunger and limiting the effects of . Insights like these lead to new questions and crucial next steps.

"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," says co-author Snigdhansu Chatterjee of the University of Minnesota's School of Statistics.

The Institute's Global Landscapes Initiative, whose contributors to this study included Ray, Paul West and James Gerber, has previously produced global scale findings that have been put to use by international organizations such as the U.N., World Bank and Brookings in evaluation of global food security and environmental challenges. The scholars say this report has implications for major food companies, commodity traders and the countries in which they operate, as well as for citizens worldwide.

"The research documents how change is already happening, not just in some future time," says Ray.

Explore further

Climate extremes explain 18%-43% of global crop yield variations

More information: Deepak K. Ray et al. Climate change has likely already affected global food production, PLOS ONE (2019). DOI: 10.1371/journal.pone.0217148
Journal information: PLoS ONE

Citation: Climate change is already affecting global food production—unequally (2019, May 31) retrieved 18 August 2019 from
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Jun 01, 2019
observed climate change causes a significant yield variation in the world's top 10 crops

If by "observed" you mean they observed the results of computer model calculations estimating impacts; otherwise no. No one has measured a reduction in production of these food crops due to "global warming", er, "climate change". In fact the long term global trend continues to show an increase in total yield and production efficiency, feeding more people on less land, thanks to improving agricultural technology and methods. What the authors of the study "discovered" is that there are regional variations in yields due to random events like floods, droughts, freezes, and severe storms; in other words, weather. But hey, let's call it climate change because it's the catch-all term nowadays that replaces the antiquated "will of the gods". Maybe we should resort to rain dances and animal sacrifices to appease the climate change gods.

Jun 01, 2019
Northern North America. Yeah, year-round growing seasons will be so "dire." If the climate kooks are right (and they haven't been in 50 years) then lets just say this is the Northern Hemisphere's turn.

Jun 01, 2019
@assdad doesn't need to eat.

Jun 02, 2019
@assdad doesn't need to eat.

Oh, is the troll doubting the facts!? How quaint.

So, I am currently blocking trolls as a tactic. But let me take the opportunity to update my strategy on trolls, as this is the 2nd thread I found this morning that is or is almost entirely filled with trolls.

Hmm. There is enough statistics about social media to know that the troll fabrication is sparsely sourced (read: mostly anti-democratic nation troll plants, or reality challenged adults) but promoted by viral spread mechanisms. The latter is ironic since it is inflammatory and harmful - but no cure is AFAIK currently known.

Too bad, since in other cases - or at least within science - diversity is strength. But trolls are garbage. Conclusion: Reign the infection in. Block the bastards, and when there are sanely formulated arguments made by those who reads the trolls but does not get that it is garbage, respond to *that* as targeted "antitrollitic",

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