Extreme weather could trigger frequent global food shocks

Drought and wildfires in Russia pushed up crop prices worldwide (Image: Denis Rusinov/ITAR-TASS/Alamy)

The risk of extreme weather events causing global “food shocks” is set to rise sharply unless we make our systems more resilient.

Thanks to climate change, by 2050 a once in a century crop failure linked to extreme weather could happen every 10 years, according to a report from the UK’s Global Food Security Programme.

The report is based on past observations, interviews with experts and climate and crop computer models. It cannot put precise numbers on the risks because they will depend on the nature of extreme events and how we respond to them, but there is no doubt they are rising, says Tim Benton of the University of Leeds, UK, one of the authors of the report.

“The risk of severe events that would scare us is increasing, and it might increase quite rapidly,” says Benton.

Crop yields are going to become ever more variable, the report concludes. In the best case scenario, bad years might be balanced out by bumper ones – but only if there is a boost from the carbon dioxide fertilisation effect.

In the worst case, average yields will fall. This could happen if higher levels of ozone at ground level and increased problems with pests and diseases cancel out any boost from CO₂.

Global instability

There is little danger of wealthy people in the West going hungry because of food shocks, but they could be affected by political instability triggered by volatility in food prices in places like the Middle East and North Africa. In 2010, for instance, a heatwave reduced wheat production in Russia, leading to an export ban that sent food prices soaring and led to protests that helped spark the Arab Spring.

There are also “pinch points” in our transport systems that could make any crisis worse if they were disrupted by extreme weather or instability.

“A lot of food goes through the Suez canal, where activists were shooting rocket-propelled grenades at ships the other year,” says Rob Bailey of Chatham House think-tank in the UK.

Gulf countries are most vulnerable because they import so much food through these pinch points, but other countries face risks too. “If the UK lost the east coast ports because of a storm surge, we’d be in deep doodah whichever way you cut it,” says Benton.

The report recommends a series of measures to increase resilience to food shocks, from persuading governments not to impose export bans when a shock hits to reducing biofuel production.

It says agriculture faces a triple challenge: boosting yields even as the world warms to feed a growing global population, reducing its impact on the environment and becoming more resilient to increasingly extreme weather.

Meanwhile, other researchers are saying that to have any chance of limiting global warming to 2°C, we need suck CO₂ out of the atmosphere by burning biomass and capturing and storing the CO₂. But vast amounts of land would be needed to grow biomass on the scale required. It is hard to see how agriculture can meet all of these challenges.