Quantcast

World Can Meet Growing Food Demands and Limit Warming to 1.5°C, Study Says

Popular
Rice drying in Nepal. foto_morgana / Flickr

By Daisy Dunne

Agriculture and food production is responsible for around 30 percent of global greenhouse gas emissions. Slashing the sector's emissions is considered to be key to limiting global warming to 1.5°C above pre-industrial levels, which is the aspirational target of the Paris agreement.

However, adopting negative emissions strategies, such as soil carbon management, will be essential to help the farming industry reduce its carbon footprint without threatening the global food supply, the lead author told Carbon Brief.


The new study marks an important step in our understanding of how to tackle the "wicked problem" of food insecurity in a changing climate, another scientist told Carbon Brief.

Making a meal of the planet

Food production contributes to global warming in a number of ways. Agricultural machinery and the transportation of crops and animals cause the release of CO2, crop fertilizers release nitrous oxide, and methane is released by rice paddy fields and livestock.

Growing demand for food has also led to the global expansion of farmland at a rate close to 10 million hectares (approximately 24.7 million acres) per year during the past decade. Some of this land once supported rainforests, which stored huge stocks of carbon.

Overall, the production of food is thought to account for around 30 percent of all greenhouse gas emissions.

Cutting emissions from agriculture is, therefore, considered to be vital to limiting warming to 1.5°C above pre-industrial levels. To slash agricultural emissions, it is likely farmland expansion into forests will need to be scaled back, fertilizers used more efficiently and lost trees replanted.

However, these mitigation techniques will take up precious farmland and could have an impact on global food production, explained Dr. Stefan Frank, a researcher at the International Institute for Applied Systems Analysis (IIASA) in Vienna and lead author of the new study published in Environmental Research Letters. He told Carbon Brief:

"Reducing global emissions may affect food availability as agricultural land could be diverted from food production to energy use for fossil fuel substitution, such as biofuels. Mitigation efforts may also limit land available for agricultural expansion due to the need for protection of high carbon landscapes, such as forests."

Crunching the numbers

His research investigates how strategies to cut emissions from the agriculture, forestry and other land use (AFOLU) sector could affect both global warming and food availability by 2050.

The research uses mathematical models to simulate the expected fall in emissions if the agricultural and land use sector employed mitigation strategies with the aim of limiting warming to 1.5°C above pre-industrial levels by 2050.

The study found that, if key mitigation strategies are implemented, the agriculture and land use sector could cut its emissions from 12 billion tonnes of CO2 a year to around 600,000 million tonnes of CO2 a year by 2050.

One way to meet this goal would be to introduce a "carbon tax" on food, the study found, whereby foods that cause high carbon emissions during their production, such as beef and rice, are taxed the most.

This tax could encourage agricultural businesses to find ways to reduce their carbon emissions, Frank said. He added:

"For this study, we use an economic land use and mimic different climate change mitigation policies implementing emission reduction targets and bioenergy demands. The emission reduction targets are achieved by implementing a carbon price in the model, which incentivizes the shift towards more greenhouse gas efficient production systems."

The chart below shows how a tax on carbon emissions could affect the price of food in relation to today's prices. Deep red represents a scenario whereby a tax of $150 dollars per tonne of CO2 emissions is applied, whereas pale pink shows a scenario where a relatively lower tax of $10 dollars per tonne of CO2 emissions is introduced.

Graph showing how a tax on carbon dioxide emissions could affect the price of food in relation to today's prices.Frank et al. (2017)

However, although the introduction of a carbon tax could help to cut farming emissions, it could also threaten the food security of the world's most vulnerable people, the research suggests.

This is because a tax on food could restrict the calorie intake of low-earners who are vulnerable to food price hikes. In many parts of the developing world, poor people spend as much as 60 to 80 percent of their income on food, according to the World Food Programme.

Using models that consider these caveats, the researchers simulated how a range of carbon taxes on food production could affect the average calorie intake across the globe by 2050, if efforts are made to limit warming to 1.5°C above pre-industrial levels.

They found that carbon taxes on food production could result in global food calorie losses ranging from 110 to 285 kcal per person, per day, by 2050, depending on the level of tax that is introduced and the market conditions. This could translate into a rise in undernourishment of 80-300 million people in 2050, the researchers said.

However, the assumption that a fall in calorie intake will lead to a rise in undernourishment and lower food security could be too simplistic, said Tim Benton, a professor in population ecology at food security at the University of Leeds, who was not involved in the study. He told Carbon Brief:

"[The analysis] tackles only a part of the whole issue. Globally, poor diets are driving ill-health through providing too many calories and not enough nutrition, so what we produce and how we produce it needs to change to provide healthier diets: calories are not a good proxy for food security."

'Win-win' strategies

However, the potential rise in undernourished people as a result of a carbon tax on food could be stemmed if "win-win" emissions mitigation strategies are also implemented, the research suggests.

One "win-win" strategy outlined by the research is soil carbon sequestration, or the introduction of farming methods that encourage soil to absorb more carbon from the atmosphere. It is considered to be a "win-win" mitigation strategy because it can help to boost crop productivity as well as lower agricultural emissions. Frank said:

"There are of course uncertainties related to the mitigation potential from soil carbon sequestration, but if these potentials were to be achieved, the impacts on food security could be significantly eased."

The research found that introducing soil carbon management on a global scale could enable us to achieve the target of limiting warming to 1.5°C at a "considerably lower calorie cost," said Frank.

The models found that introducing good soil management could reduce the fall in daily calorie intake by 65 percent, when compared with scenarios that do not consider carbon sequestration.

Using "win-win" strategies, such as soil carbon management, could make limiting warming to 1.5°C while maintaining food security a realistic goal. Frank explained:

"There are several other "win-win" options such as reducing food waste and harvest losses, or societal dietary change that were not explicitly assessed in this study but if realized together, they could even enable us to achieve this goal [of limiting warming to 1.5°C above pre-industrial levels] without compromising food security at all."

The study offers us insight into how the causes of food insecurity as a result of climate change are often complex and indirect, said Benton:

"Rising food insecurity is painful to contemplate, but it is a wicked problem. Without mitigating climate change, its impacts on food security are also likely to increase the number of food insecure, either directly or indirectly (through promoting conflict).

"This is an important study which shows that carbon pricing can drive positive effects, but can also drive negative effects. It sets an agenda about how to avoid the negatives, whilst embracing the positives."

EcoWatch Daily Newsletter

Artist's conception of solar islands in the open ocean. PNAS

Millions of solar panels clustered together to form an island could convert carbon dioxide in seawater into methanol, which can fuel airplanes and trucks, according to new research from Norway and Switzerland and published in the Proceedings of the National Academy of Sciences journal, PNAS, as NBC News reported. The floating islands could drastically reduce greenhouse gas emissions and dependence on fossil fuels.

Read More Show Less
Marcos Alves / Moment Open / Getty Images

More than 40 percent of insects could go extinct globally in the next few decades. So why did the U.S. Environmental Protection Agency (EPA) last week OK the 'emergency' use of the bee-killing pesticide sulfoxaflor on 13.9 million acres?

EcoWatch teamed up with Center for Biological Diversity via EcoWatch Live on Facebook to find out why. Environmental Health Director and Senior Attorney Lori Ann Burd explained how there is a loophole in the The Federal Insecticide, Fungicide, and Rodenticide Act under section 18, "that allows for entities and states to request emergency exemptions to spraying pesticides where they otherwise wouldn't be allowed to spray."

Read More Show Less
Sponsored

Zero Waste Kitchen Essentials

Simple swaps that cut down on kitchen trash.

Sponsored

By Kayla Robbins

Along with the bathroom, the kitchen is one of the most daunting areas to try and make zero waste.

Read More Show Less
View of downtown Miami, Florida from Hobie Island on Feb. 2, 2019. Michael Muraz / Flickr

The Democratic candidates for president descended upon Miami for a two-night debate on Wednesday and Thursday. Any candidate hoping to carry the state will have to make the climate crisis central to their campaign, as The New York Times reported.

Read More Show Less
A pumpjack in the Permian Basin. blake.thornberry / Flickr

By Sharon Kelly

On Monday, the Wall Street Journal featured a profile of Scott Sheffield, CEO of Pioneer Natural Resources, whose company is known among investors for its emphasis on drawing oil and gas from the Permian basin in Texas using horizontal drilling and hydraulic fracturing, or fracking.

Read More Show Less
Sponsored
Pexels

By Craig K. Chandler

The federal government has available to it, should it choose to use them, a wide range of potential climate change management tools, going well beyond the traditional pollution control regulatory options. And, in some cases (not all), without new legislative authorization.

Read More Show Less
Denis Poroy / Getty Images

By Dan Gray

Processed foods, in their many delicious forms, are an American favorite.

But new research shows that despite increasing evidence on just how unhealthy processed foods are, Americans have continued to eat the products at the same rate.

Read More Show Less

By Sarah Steffen

With a profound understanding of their environmental surroundings, indigenous communities around the world are often cited as being pivotal to tackling climate change.

Read More Show Less