Will stores run out of bread? Food security faces new threats

Global warming, unforeseeable weather conditions and extreme climate events* also influence the availability of food. For example, the climate resilience of European wheat crops has declined. This puts global food security at risk.

As a result of global warming, the growing seasons of cereals are undergoing changes.

"We do not know how the climate will change in specific parts of Europe or even within a given country. It is increasingly difficult to prepare for the future when farms are unable to anticipate even average weather conditions, let alone weather variability and extremes or crop yield responses", outlines Helena Kahiluoto, Professor of Sustainability Science.

Our turbulent time is also characterised by conflicts and turmoil related to trade, food price volatility and climate migration, which are aggravated by extreme weather and yield losses. Events such as these undermine food security.

Food security exists when all people at all times have access to sufficient, safe and nutritious food that meets their needs for a healthy and active life. This is one of the topics Kahiluoto and her Sustainability Science Group at LUT University cover in their studies on enabling the sustainability transformation of the food-energy-water nexus.

"Our starting point is uncertainty. How can we make sure that the food system keeps functioning even though we are unable to anticipate the changing conditions?"

Insurance against changing weather conditions and prices?

Provisions can be made to secure the availability of food by enhancing the climate resilience of production and food chains. In this context, resilience refers to preparing for and adapting to uncertainty and variability – the ability to produce food in changing circumstances.

In agriculture, which is the most important source of food for humanity, climate resilience can be strengthened through diversification tailored to protect crops from possible disturbances. In other words, farmers start cultivating a few crop varieties or crops which react in different ways to heavy rains, drought or market situations. The prices of the planned product range will not fluctuate at the same time and in the same direction.

"A diversity of responses is an insurance: you won't lose everything due to changes in the weather or markets. It means safety not only for the producer but also for the retailer and consumer", Kahiluoto explains.

Diversity has often been interpreted as inefficiency. According to the sustainability researcher, this idea must be abandoned because we are living in a time where anticipation is difficult. 

"A maximum yield from one crop variety on a highly specialised farm was a good objective when conditions could be foreseen. However, this is not the way to achieve efficiency in a changing climate or volatile markets. Now, efficiency also requires security," Kahiluoto emphasises.

In 2016, Kahiluoto and her colleague Janne Kaseva published a study based on farm bookkeeping data revealing that land-use diversity does not reduce the resource-use efficiency of the farm. Well-planned diversity may even increase the efficiency of the farm, as the peak seasons will not coincide with each other.

Food security through responses to weather

Climate resilience can be enhanced with response diversity or tailored diversification (1). For example, wheat could withstand changing weather conditions better if seeds of several different wheat varieties were planted on the same farm or in the same region – varieties with different weather responses.

"If we put together a group of varieties with different responses to the most critical weather disturbances, the crop will not be lost entirely", Kahiluoto reasons.

Not just any diversity will help, but diversity in responses, ‘response diversity', will. It introduces efficiency to diversity.

An example of extensive crop losses and their consequences was the summer of 2018, when Europe widely suffered from drought. Kahiluoto relates that countless farms in Europe had to slaughter livestock due to a lack of fodder.

Empirically assessed response diversity could have helped to anticipate and prevent such losses.

"Response diversity is based on analyses of how different varieties have responded to different weather conditions and where. Data helps to understand what varieties should be combined to secure diversity and produce a balanced crop regardless of the weather", Kahiluoto elaborates.

Decreased climate resilience of European wheat

In a recent study, Kahiluoto and co-workers mined data to analyse the climate resilience of European wheat (2). The data included 101 000 cultivar observations regarding spring wheat, winter wheat and durum wheat during the years 1991–2014. Data was collected from Finland, Denmark, Belgium, France, Germany, Slovakia, the Czech Republic, Spain and Italy.

The study indicated that the climate resilience of European wheat had declined across the board.

Diversity is also important in terms of food market channels.

- Helena Kahiluoto

"The number of wheat varieties has increased over the years, but they are increasingly similar in their responses to weather events", Kahiluoto says.

The LUT University professor states that any breeding should take into account climate resilience alongside yield potential and resistance to diseases and pests.

"In fact, wheat is crucial to food security in Europe. Globally, it is the most important source of vegetable protein."

Climate resilience belongs at the core of agricultural policy

Breeding that promotes the climate resilience of staple crops such as wheat and the cultivation of a diversity of crops responding differently to weather extremes are what Professor Kahiluoto wishes as the outcomes of the EU's Common Agricultural Policy (CAP) for the sake of food security.

Economic incentives and collaboration between breeders, seed traders and national security authorities could be employed: "Could agricultural subsidies be contingent on preparing for varying weather, or could response diversity constitute grounds for a discount on voluntary crop insurance?"

The most important thing is to take climate resilience into account in food production and in related evidence-based decision-making. Kahiluoto and her team have proposed a concrete solution for enhancing food security: diversity as a response to disturbances.

"Diversity is also important in terms of food market channels. The situation becomes difficult if retail stores focus their procurement on one climatic region which then suffers from crop losses. Similarly, by ordering bread also from small bakeries a store makes provisions for strikes of larger chains", Kahiluoto states.

In other words, response diversity is as important in other strategic areas. For example, the energy system is vulnerable if one supplier susceptible to certain disturbances, such as conflicts or embargos, has an abundant share.

"The supply of energy must be secured in a way that one disturbance could never paralyse the majority of the system. Sources and channels not affected by the disturbance must be available, and it should be possible to increase their share rapidly if needed", Kahiluoto continues.

Sustainability reform instead of adaptation

Kahiluoto reminds us that even though response diversity is a simple and effective way to improve stability in a turbulent world, it is not enough. Even the best ways to adapt to a situation are merely quick fixes. Global food security requires curbing climate change and the redistribution of resources (3). Also the population growth must be abated by making high-quality education and health care available to everyone.

"Food security and stability require the reduction and redistribution of resource consumption. To achieve this, we need to understand that our own destiny is tied to that of other people on the globe. Sustainability science is searching for solutions in accordance with this", Kahiluoto concludes.

Food security and stability require the reduction and redistribution of resource consumption.

- Helena Kahiluoto

Vocabulary: extreme climate event

An extreme climate event means climatic elements such temperatures, precipitation and wind that swing from one extreme to the other every few years. The current climate change is believed to contribute to this phenomenon in the coming decades.

Original arcticles:

1) Kahiluoto et al 2014. Cultivating resilience by empirically revealing response diversity. Global Environmental Change – Human and Policy Dimensions 25: 186–193.

 2) Kahiluoto et al 2018. Decline in climate resilience of European wheat. PNAS

Kahiluoto et al 2015. Local and social facets of planetary boundaries: right to nutrients. Environmental Research Letters 10, 104013.

Research Highlight at Nature Climate Change: "Declining yield resilience".  (Paywall)

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Reply to Snowdon et al. and Piepho: Genetic response diversity to provide yield stability of cultivar groups deserves attention