A warming world threatens our food supplies

Global warming is exacerbating political instability as tensions brought on by food insecurity rise, and new research suggests the issue can only get worse

By John Vidal  /  The Guardian, LONDON

Thu, Apr 18, 2013 - Page 9

When Tunisian street vendor Mohamed Bouazizi set himself on fire on Dec. 17, 2010, it was in protest at heavy-handed treatment and harassment in the province where he lived. However, a host of new studies suggest that a major factor in the subsequent uprisings, which became known as the Arab spring, was food insecurity.

Drought, rocketing bread prices, food and water shortages have all blighted parts of the Middle East. Analysts at the Center for American Progress in Washington say a combination of food shortages and other environmental factors exacerbated the already tense politics of the region. As the Observer reported on Sunday, an as-yet unpublished US government study indicates that the world needs to prepare for much more of the same, as food prices spiral and longstanding agricultural practices are disrupted by climate change.

“We should expect much more political destabilization of countries as it bites,” said Richard Choularton, a policy officer in the UN’s World Food Programme climate change office. “What is different now from 20 years ago is that far more people are living in places with a higher climatic risk; 650 million people now live in arid or semi-arid areas where floods and droughts and price shocks are expected to have the most impact.

“The recent crises in the Horn of Africa and Sahel may be becoming the new normal. Droughts are expected to become more frequent. Studies suggest anything up to 200 million more food-insecure people by 2050 or an additional 24 million malnourished children. In parts of Africa we already have a protracted and growing humanitarian disaster. Climate change is a creeping disaster,” he said.

The Mary Robinson Climate Justice Foundation hosted a major conference in Dublin on Monday and Tuesday. Research presented there said rising incomes and growth in the global population, expected to create 2 billion more mouths to feed by 2050, will drive food prices higher by between 40 percent and 50 percent.

“We must prepare today for higher temperatures in all sectors,” said Gerald Nelson, a senior economist with the International Food Policy Research Institute in Washington.

All of the studies suggest the worst impacts will be felt by the poorest people.

“Climate change is already having a domino effect on food and nutritional security for the world’s poorest and most vulnerable people. Child malnutrition is predicted to increase by 20 percent by 2050. Climate change impacts will disproportionately fall on people living in tropical regions, and particularly on the most vulnerable and marginalized population groups. This is the injustice of climate change — the worst of the impacts are felt by those who contributed least to causing the problem,” said Robinson, the former Irish president.

However, from Europe to the US to Asia, no population will remain insulated from the huge changes in food production that the rest of the century will bring.


Many African countries are already experiencing longer and deeper droughts, floods and cyclones. The continent is expected to suffer disproportionately from food insecurity, due to fast-growing vulnerable populations.

Egypt expects to lose 15 percent of its wheat crops if temperatures rise 2°C, and 36 percent if the increase is 4°C. Morocco expects crops to remain stable up to about 2030, but then to drop quickly later. Most North African countries traditionally import wheat and are therefore highly vulnerable to price shocks and droughts elsewhere.

A new study of 11 West African countries expects most to be able to grow more food as temperatures rise and rainfall increases. However, demand from growing populations may double food prices. Climate change may mean Nigeria, Ghana and Togo can grow and export more sorghum, raised for grain.

Temperatures are expected to rise several degrees in regions close to the Sahel. In Burkina Faso, the sorghum crop is expected to decline by 25 percent or more, but maize yields may improve.

Other studies by the International Food Policy Research Institute suggest crop yields across sub-Saharan Africa may decline 5 percent to 22 percent by 2050, pushing large numbers of people deeper into destitution.

A new UN study suggests climatic conditions in southern Africa will worsen. Climate models mostly predict an increase in annual maximum temperatures in the region of 1°C to 2°C by 2050. This will favor some crops but shift others to higher ground or further north.

Both of Africa’s staple crops, maize and sorghum, are expected to be badly hit by increasing severity of weather.

Oxfam warns that small-scale farmers in the Horn of Africa will bear the brunt of the negative impacts of climate change. Unpredictable weather here has already left millions semi-destitute and dependent on food aid.


The US is expected to grow by 120 million people by 2050. Government scientists expect more incidents of extreme heat, severe drought, and heavy rains to affect food production. The warming is expected to continue without undue problems for 30 years, but beyond 2050 the effects could be dramatic with staple crops hit.

According to the latest government report: “The rising incidence of weather extremes will have increasingly negative impacts on crop and livestock productivity, because critical thresholds are already being exceeded. Many agricultural regions of the US will experience declines in crop and livestock production. Climate disruptions have increased in the recent past and are projected to increase further over the next 25 years.”

California’s Central Valley will be hard-hit with sunflower crops, wheat, tomato, rice, cotton and maize all expected to lose 10 percent to 30 percent of their yields, especially beyond 2050. Fruit and nut crops, like cherries, grapes and groundnuts, which depend on having a certain number of “winter chilling” days may have to relocate. Animals exposed to many hot nights are increasingly stressed. Many vegetables crops will be hit when temperatures rise only a few degrees above normal.

Because nearly 20 percent of all US food is now imported, climate extremes in countries that supply the US will affect the price of US food. In 2011, 14.9 percent of US households did not have secure food supplies and 5.7 percent experienced very low food security.

Because few crops can withstand average temperature rises of more than 2°C, Latin America expects to be seriously affected by a warming climate and more extreme weather events. Even moderate 1°C to 2°C rises in temperatures would cause significant damage to Brazil, which has emerged as one of the world’s biggest suppliers of food crops. Brazilian production of rice, coffee, beans, manioc, maize and soya are all expected to decline, with coffee, a mainstay of many other Latin American economies, especially vulnerable because it is so sensitive to heat and diseases.

Other studies suggest Brazil’s massive soya crop, which provides animal feed for much of the world, could slump by more than 25 percent over the next 20 years. The knock-on effects would mean higher meat prices in Europe.

Two major crops should do well. Quinoa and potatoes, which have hundreds of varieties and can be cultivated from sea level up to 4,000m have been developed over hundreds of years to adapt to extreme conditions.


China is relatively resilient to climate change. Its population is expected to decline by up to 400 million people this century, easing demand on resources, and it has the capacity to buy in vast quantities of food. However, because more and more Chinese are changing to a richer, more meat-based diet, the challenges will be to access more land and cattle feed. Climate change will affect regions differently, but many crops are expected to migrate north.

Crop losses are increasingly being caused by extreme weather events, insect attacks and diseases. The 2011 drought lifted food prices worldwide. Wheat is becoming increasingly difficult to grow in some northern areas of China as the land gets drier and warmer. In southern China, droughts in recent years have replaced rainy seasons. China’s National Academy of Agricultural Sciences expects basic food supplies to become insufficient around 2030.

A new study for USAID expects most of Vietnam, Cambodia, Laos and Thailand to see 4°C to 6°C temperature rises by 2050. The Lower Mekong region of 100 million people, which is prone to weather extremes, could also see rainfall increase 20 percent or more in some areas, reducing the growth of rice and other staple crops. Many provinces will see food production decline significantly. The number of malnourished children in the region may increase by 9 million to 11 million by 2050.

Extreme events will increasingly affect agriculture in Australia. Key food-growing regions in the south are likely to experience more droughts in the future, with part of western Australia having already experienced a 15 percent drop in rainfall since the mid-1970s. The number of record-breaking hot days in Australia has doubled since the 1960s, also affecting food output.


Climate change affects agricultural production through its effects on the timing, intensity and variability of rainfall and shifts in temperatures and carbon dioxide concentrations.

Crops normally seen growing in the south of Europe will be able to be grown further north. This would allow more sweetcorn, grapes sunflowers, soya and maize to be grown in Britain. In Scotland, livestock farming could become more suitable. At the higher latitudes warmer temperatures are predicted to lengthen and increase the intensity of the growing season. However, the combined effect of extra carbon dioxide in the atmosphere, which can stimulate plant growth, and a major temperature rise, could mean a decrease in yields of around 10 percent later in the century.

Latest EU projections suggest the most severe consequences of climate change will not be felt until 2050. However, significant adverse impacts are expected earlier from extreme weather events, such as more frequent and prolonged heat waves, droughts and floods. Many crops now grown in southern Europe, such as olives, may not survive high temperature increases. Southern Europe will have to change the way it irrigates crops.


In Europe’s high and middle latitudes, global warming is expected to greatly expand the growing season. Crops in Russia are expected to be able to expand northwards but yields will be much lower because the soils are less fertile. In the south, the climate is likely to become much drier which will reduce yields. In addition, climate change is expected to increase the scarcity of water resources and encourage weed and pest proliferation.

Many Russian regions were hit by an extreme heatwave in 2011, which forced the government to ban exports of wheat and grains. Warming will increase the number of forest fires by 30 percent to 40 percent. This will affect soil erosion and increase the probability of floods.

In the Middle East and North Africa, declining yields of up to 30 percent are expected for rice, about 47 percent for maize and 20 percent for wheat.