Climate change harms food
We all know that climate change is changing our world in ways that will leave a devastating impact on our environment. But did you know that our global food sources are also showing the effects of rising CO2 emissions—affecting the very nutrients we count on for human health?
We know that climate change is one of the most pressing issues facing humankind today. Besides consequences such as ongoing ice melt and rising sea levels, however, global warming will also affect us all by impacting one of the basic necessities of life: the food we eat.
The United Nations (UN) estimates that the global mean temperature will rise by about 1.5 to 2.5 degrees Celsius above pre-industrial levels by the end of this century. What this means in terms of nourishment is a negative effect on all aspects of food security—supply, access, and stability—as well as nutrition.
Weather extremes are a driver behind the recent increase in global hunger.
In 2017, world hunger rose for the third year in a row, reaching 821 million, or about one in nine people, according to the Food and Agriculture Organization of the UN’s report State of Food Security and Nutrition in the World 2018.
“In all likelihood, climate change will make food harder and more expensive to produce,” says Evan Fraser, director of the University of Guelph’s Arrell Food Institute. “The worst hit regions will include areas around the equator that are expected to become hotter and drier, with some projections suggesting they may even exceed levels of crop tolerance.”
“In addition, more extreme weather and less predictable pest patterns will make farming much harder,” he adds. “The challenge of feeding the world’s growing population in a way that is equitable, sustainable, and nutritious is one of the defining challenges of the century.”
The 2018 UN report shows that hunger and malnutrition are markedly worse in agrarian countries that are dependent on rainfall or experience drought.
“We know climate change is going to affect the ability of people to grow and access the food they need; we know this because it’s already happening,” says Darcy Knoll, communications specialist for CARE Canada, a charitable organization that works to end poverty and achieve social justice. “I was in southern Zimbabwe earlier this year, and the message I heard repeatedly was that shifting weather patterns are putting increasing strain on the ability of farmers to plan ahead.”
The impact of climate change on food security will be especially detrimental to the world’s poorest women. According to the Intergovernmental Panel on Climate Change, the effects of climate variability and extreme weather events, such as floods, storms, and cyclones, will likely increase existing inequalities and vulnerabilities between men and women.
“The majority of the world’s smallholder farmers are women,” Knoll says. “When food is scarce, women and girls suffer most, often being the last to eat, and carrying an increasing burden as climate change impacts rural livelihoods. Climate change will make their lives much harder.”
“When migration becomes a way of coping with climate change, men and youth typically migrate to cities looking for new opportunities, leaving women, young children, and the elderly behind to sustain increasingly precarious local economies,” Knoll says.
What’s equally troubling is how rising carbon emissions can compromise certain crops’ nutritional quality.
According to a 2018 study published in the research journal Nature, the current level of carbon dioxide in the atmosphere is around 410 parts per million (ppm), while climate projections show that this concentration could escalate to 550 ppm over the next few decades.
This increase will mean severe changes in the atmospheric conditions that crops are accustomed to growing in, altering the foods’ nutrient levels.
The study found that higher carbon dioxide levels reduced the levels of certain essential nutrients as well as protein by between three and 17 percent in wheat, rice, maize, and soybeans.
By 2050, more than 175 million people will become zinc deficient, 122 million people will be protein deficient, and more than 1 billion women and children could lose some of their dietary iron intake, the Nature study found. Such nutritional deficiencies are associated with greater risk of anemia, impaired cognitive function, autoimmune diseases, and psychological disorders.
“Rising CO2 levels have all these implications that flow through to our food systems,” says Matthew Smith, research fellow in the environmental health department at the Harvard T.H. Chan School of Public Health and co-author of the Nature study.
“There’s an insidious part of this effect, because it goes on without you really noticing. By eating the same number of calories while the amount of nutrients accompanying those calories is going down, you’re opening yourself to a higher risk of deficiencies without even knowing it.
“There are large swaths of the world that would take the brunt of these effects, where the bulk of their diets are grains or vegetables,” he adds. “Rice is the most important food for many nutrients, and if you’re reducing its nutrient content, there are huge health effects, consequences that are not being borne by high-emitting nations but by poorer, less industrialized nations. The effects are broad and far-reaching.”
While slowing climate change may seem like a daunting task, there are ways to help reverse the trend and bolster food security around the world.
One way to help farmers adapt is through a combination of technologies that promote more resilient crops and livestock, crop insurance programs that protect farmers against loss during bad years, and poverty reduction strategies so that the world’s poorest farmers are not left completely destitute if their crops fail, Fraser says.
Individuals can lobby government to develop policies that reward farmers for using farming practices that build up soil organic matter and promote crop diversity. “Building up soil organic matter through crop rotation and adding manure to the soil can really help protect crops against both droughts and floods,” Fraser adds.
Programs like CARE’s help people in developing nations conserve rainwater and grow more drought-resistant crops.
Consumers can also work to minimize their own carbon footprint by reducing food waste and eating healthier diets that are abundant in fruits and vegetables.
The 2018 UN report calls for people to reduce their intake of animal products by 30 percent. While estimated figures vary, livestock production results in significant greenhouse gas emissions. Plant-based diets also use less water, oil, and land compared to a meat-heavy diet.
“This is not to say we all need to become vegetarian; animals not only play a vital part of a sustainable agricultural ecosystem but are also culturally important for people around the world,” Fraser says. “With that said, we will all probably have to consume less meat in the future.”
“I am not pessimistic,” Fraser adds of the challenge ahead. “I believe that a combination of emerging new digital technologies, consumer choices for more sustainably produced products, and good policies that reward farmers for using production methods that reduce greenhouse gas emissions will help ensure that we devise the systems to feed the future.”