Research claims climate variability is responsible for at least 30% of the annual fluctuations in worldwide agricultural yield


A new study highlights the threats of a changing climate to food production (Credit: Pixabay/SwidaAlba)

Climate change could lead to an increased risk of unusually low agricultural harvests, with wheat highlighted as one of the most critical crops under threat, a study has found.

Compiled by Austria-based research organisation, the International Institute for Applied Systems Analysis (IIASA), the report states that extreme temperatures could have negative impacts on countries responsible for growing most of the world’s food.

The analysis, published in the journal Nature Climate Change, says these areas are at risk of failing to produce enough wheat, maize and soybean needed to meet global demands.

IIASA researcher Franziska Gaupp said: “Climatic connections between global phenomena such as the El Niño Southern Oscillation (ENSO) and regional climate extremes such as Indian heatwaves, or flood risks around the globe pose a risk to the global food system.

“Climatic shocks to agricultural production contribute to food price spikes and famine, with the potential to trigger other systemic risks, including political unrest and migration.

“This analysis can provide the basis for a more efficient allocation of resources to contingency plans and strategic crop reserves that would enhance the resilience of the global food system.”


IIASA findings into why climate change is threatening wheat and other crops

The IIASA, which conducts research into the critical issues of global environmental, economic, technological and social change, claims the study is the first of this type and scale.

It says that, while the possibility of a climatic extreme hitting more than one area responsible for growing much of the world’s food has been a growing cause for concern, only a few studies have investigated the probability of simultaneous production shocks.

The study’s co-author and IIASA researcher Stefan Hochrainer-Stigler said: “Our approach is able to estimate simultaneous large-scale extreme climatic events in a risk-based manner, and therefore enables the development of new risk response strategies.”

Climate change could lead to a shortage in supply of wheat (Credit:

The IIASA says climate change is not just resulting in a steady increase in temperatures, but also in an increased frequency and severity of extreme climatic events, including drought, heatwaves, and floods.

It believes the extreme conditions are particularly damaging for agriculture and states that climate variability is responsible for “at least” 30% of the annual fluctuations in worldwide agricultural yield.

The study highlights that, under “normal” climatic conditions, the global food system can compensate for local crop losses through grain storage and trade.

But it is doubtful whether the current arrangement is resilient to more extreme climatic conditions, according to the IIASA.

The research looks at climatic and crop yield data for the main agricultural regions within the highest crop-producing countries by mass from 1967 to 2012.

It shows there has been a significant increase in the probability of multiple global breadbasket failures for particularly wheat, maize, and soybeans.

For soybeans, the implications of crop failure in all major breadbaskets associated with climate risk would be “at least” 12.55 million tons of crop losses.

This exceeds 7.2 million tons of losses in 1988–1989, one of the largest historical soybean production shocks.


Positive and negative correlations between the world’s breadbasket and climate dependence

On a global scale, there are both negative and positive correlations between the world’s breadbaskets and climatic dependence, according to the study.

Precipitation-based risks for soybean breadbaskets in India and Argentina are negatively correlated. Heavy rainfall in India would negatively affect the country’s soybean harvest, but this could be mitigated by imports from Argentina – meaning crop losses would be balanced.

Conversely, there is a positive correlation between maximum temperatures in the EU and Australia, for example. The risk of increasing temperatures in Australia brought about by climate change could affect the amount of wheat the country can export to the EU. This would then place additional pressure on the EU in case of drought during its wheat season.