How climate change threatens food security — and why we’re all at risk

October 23, 2019

Climate change is a threat multiplier for hungry and undernourished people. Combined with conflict, it destroys livelihoods, drives displacement, widens inequalities, and undermines sustainable development — including our goal of zero hunger by 2030. This piece is adapted from Rupa Mukerji’s essay, “Climate Change and Hunger,” published as part of the 2019 Global Hunger Index (coproduced by Concern and Welthungerhilfe).

For hungry and undernourished people, climate change is a threat multiplier. Since the early 1990s, the number of extreme weather-related disasters has doubled. This has reduced the yields of major crops and contributed to an increase in food prices and a decrease in income.

These disasters have also disproportionately harmed low-income people and their access to food, which is why we have chosen to focus on the connection between climate change and food security in the 2019 Global Hunger Index (GHI), prepared by Concern Worldwide and Welthungerhilfe. Sadly, this is not a trend that appears to be going away any time soon. Looking ahead, climate models predict higher average temperatures in most land and ocean regions, hotter extremes in many inhabited regions, and both heavy precipitation and an increasing probability of drought in some areas. These are all additional challenges for reducing hunger.

Since 2000, we’ve reduced global hunger on a proportionate level. But in absolute terms, the number of people going to bed hungry is on the rise.

While the world has made gradual progress in reducing hunger on a global scale since 2000, this progress has been uneven. We’ve reduced global hunger, but in absolute terms, the number of people going to bed hungry is on the rise. The GHI takes into account the rates of undernourishment, child stunting, child wasting, and child mortality to highlight where action is most needed to fight hunger. With 2019’s data now available (along with an updated ranking of the world’s hungriest countries), let’s take a look at some of the ways climate change threatens food security — and how that may impact all of us.  

Climate change and food security: Fast facts

  • Climate change is a threat multiplier for hungry and undernourished people.
  • Countries with high levels of hunger are often also highly vulnerable to climate change, and have a low capacity to adapt.
  • Climate change affects food production and availability, access, quality, utilization, and stability of food systems. In short, it impacts all aspects of the food system.
  • Extreme weather-related disasters are increasing and reduce the yields of major crops. 
  • Higher levels of CO2 reduce the nutritional value of crops
  • The global food system contributes about one-third of greenhouse gas emissions. About ⅔ of food are lost and wasted from farm to table. These losses therefore exacerbate climate change without improving food security or nutrition
  • Climate change and conflict combined destroy livelihoods, drive displacement, widen inequalities, and undermine sustainable development. 
  • Ending hunger and undernutrition in a changing climate demands large-scale action

Climate change threatens agriculture and food production

Higher temperatures, water scarcity, extreme events like droughts and floods, and greater CO2 concentrations in the atmosphere have already begun to impact staple crops around the world. Maize and wheat production has declined in recent years due to extreme weather events, plant diseases, and an overall increase in water scarcity. 

According to the Food and Agriculture Organization of the United Nations, the unpredictable yield for cereal crops in semi-arid regions of the world (like the Sahel region of Africa) is at least 80% the result of climate variability. 

In other areas like Bangladesh and Vietnam, rising sea levels pose a different threat to food security. As the saltwater is more likely to flood coastal farmlands, it is also more likely to kill off rice crops. Half of Vietnam’s national rice production is centered on the Mekong Delta region, which means that a flood in this region (roughly the size of Maryland) could impact both the country’s food security and economy. 

While the causes of these issues are fairly consistent (and often not the doing of the people living in these regions), the solutions are not. This means that, with the effects of climate change already apparent in areas like the Horn of Africa and Southeast Asia, we need to find unique methods to mitigate disasters when they strike, and develop bespoke ways to reduce the impacts of hazards on the lives and livelihoods of these areas in the future. 

A Somali boy with some cows at a water trough

Animals drink water trucked into drought stricken areas of Somaliland by Concern Worldwide. Severe drought across the Horn of Africa has forced thousands of families to leave their homes in the countryside and seek help near urban centers.

Climate change limits food access

If climate change affects food production, it stands to reason that it also affects food access. This simple supply-and-demand has big impacts: Climate change and weather disasters (such as floods or drought) can lead to inflated prices for the food that is available. These price spikes leave the poorest households (urban poor and rural food-buyers) most vulnerable, with the urban poor spending up to 75% of their total budget on food alone. 

Because our food systems are increasingly dependent on one another, this means that more frequent and more extreme events in one region could disrupt clusters of food systems — even the global food system as a whole. The areas least likely to adjust to a sudden event or shock, however, continue to be the ones disproportionately affected. 

Climate change decreases nutrition and nutritional value

In many food-insecure areas, the next concern becomes nutrition. In low-income and agrarian communities, the patterns of food consumption are seasonal. A pre-harvest “lean season” will leave families reducing their food consumption (often skipping one or more meals each day) until the next harvest. With climate change reducing harvests, this means that the lean period may be extended if there are fewer supplies, or if it takes longer to get an adequate harvest. 

By 2050, an estimated additional 175 million people could have zinc deficiencies, and an additional 122 million people could be protein deficient — due to climate change.

Alternatively, climate change can adversely affect the nutritional value of food that is grown. Studies show that higher carbon dioxide concentrations reduce the protein, zinc, and iron content of crops. By 2050, an estimated additional 175 million people could have zinc deficiencies (which can, among other things, make them more susceptible to illnesses) and an additional 122 million people could be protein deficient. Communities relying largely on plant harvests for their nutrition will, again, feel this most acutely. 

Beyond plant-based nutrition, this also has a ripple effect on livestock, who rely on the same resources as humans to eat, grow, and produce meat and/or milk. Livestock are also severely threatened by drought, accounting for 36% of drought-related losses (crops account for 49%). Climate extremes also threaten fish populations, especially in areas like Southeast Asia. 

Climate change increases food waste

Rain doesn’t guarantee healthy crops, either. Higher rainfalls or flooding can produce toxic mold on crops. Crops grown in high-drought areas that are then moved into humid storage facilities are vulnerable to fungal infections or pests. The more climate changes and the more that extreme climate events become commonplace, the more food we lose on an annual basis. 

A Turkana woman with her mother-in-law and children in drought-struck northern Kenya.

Ng’ikario Ekiru with her mother-in-law Nakode and three of her children, Aukot, Ekuwom and Apua. The family live in Turkana, a part of northwestern Kenya plagued by drought. Photo: Gavin Douglas / Concern Worldwide.

According to the UN’s Food and Agriculture Organization, roughly one-third of the food produced by farmers is lost between the field and the market in low- and middle-income countries. In high-income countries, a similar amount is wasted between the market and the table. Currently, the food system contributes 21–37% of greenhouse gases, meaning that these food losses add to the climate crisis but do nothing for food security or malnutrition levels. 


Climate change affects the global food system in such a way that those who already suffer from hunger and undernutrition are those most vulnerable to these added threats. In order to end hunger — one of the UN’s top Sustainable Development Goals for the year 2030 — we therefore need to also tackle the current climate crisis, particularly the topic of climate justice and the inequities that are raised by climate change. 

As we can see with the increasingly global nature of our food system, however, this cannot happen in isolation. We must foster global solidarity with the most climate-vulnerable communities and countries, with high-income countries (especially those with the highest greenhouse emissions) taking responsibility for both mitigating the causes of climate change and supporting low- and middle-income countries in adapting to the effects of these changes. All of this is a tall order, but it’s an order that will affect all of our futures, regardless of where we live.

Download the full 2019 Global Hunger Index.

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