Land use is critical for food security on a warming planet

Written by
Keely Swan, Center for Policy Research on Energy and the Environment
Sept. 30, 2019

The world is on a course to consume in 2050 more than 50% more crop calories, and 70% more meat and dairy products than in 2010. In the course of doing so, it is likely to clear hundreds of millions of acres of forests and produce far more greenhouse gas emissions.

To meet food needs for a projected population of 9.8 billion people in 2050 while solving climate change, the world must find ways to produce this additional food on the agricultural land we are currently using, hold down the growth in consumption, and limit expansion into unfarmed areas. So finds a monumental report by the World Resources Institute, World Bank and United Nations. It provides a "menu" with five '"courses" of 22 strategies for producing enough food to feed a growing planet, while also cutting greenhouse gas emissions, protecting biodiversity, and addressing global inequalities.


Cover of WRI Food Report

Penned by lead author Timothy Searchinger, a Princeton University research scholar based at the Center for Policy Research on Energy and the Environment, the report reveals how agriculture and associated land-use change already account for approximately one-quarter of global greenhouse gas emissions.

“If the world tried to produce all the food likely needed in 2050 with today’s farming systems, most of the world’s forests would have to disappear for expanded agricultural use,” Searchinger said. “Agricultural greenhouse gas emissions alone would vastly exceed the limit for emissions from human sources required to keep us within a 2⁰C warming scenario.”

Land is a finite resource, and almost half of the world's vegetated land — land other than ice, desert and semi-desert — is already used for food production to grow crops and provide pasture for cattle, sheep and other domestic animals. As agricultural land expands, the clearing of forests and savannas releases vast quantities of carbon. By contrast, climate strategies require that we restore forests and peatlands, and native habitats are also home to the vast majority of the world’s diverse species.

The report sets forth a variety of specific strategies to meet food needs without expanding our current agricultural footprint. This involves changes to policies for land use, innovations and shifts in both industrial and small-scale farming practices, as well as alterations in consumers' diets and limiting consumption of bioenergy. It also describes a range of innovative practices to reduce emissions from the agricultural production process itself, such as methane from manure and cattle and nitrous oxide from fertilizer use, and sets forth a range of policies to advance these solutions.

The challenge of producing more food on the same agricultural land footprint will become even more difficult as climate change alters ecosystems through temperature increases, water shortages, and sea-level rise. A number of regions — particularly across the Southern Hemisphere — are expected to lose arable lands and see a decrease in overall crop yields.



diagram showing how climate change may affect crop yields

Figure 1-4 from Creating a Sustainable Food Future. Source: World Bank (2010)

As some countries’ ability to produce food decline, other areas may increase food production in their more temperate regions. In either situation, people may move into new areas to farm — either because they feel the resources have been exhausted on their current lands, or because they see potential for greater profit or production in expanding – and this can have negative outcomes.

Other Princeton researchers have been studying this phenomenon of farmland expansion in the Western Amazon, as more roads and development into forests are seriously threatening wildlife. The WRI/U.N. report highlights how even if agriculture decreases in one area and expands in another, netting no total expansion, this still poses a great risk for climate change, since most often the newly converted land is rich in carbon and contains biologically diverse habitats that need to be preserved.

Policymakers have an important role to play in regulating environmental resources while also considering issues of equity on a local, national, and global scale. Farmers and scientists are also critical to studying the situation and employing solutions. Among the report's many recommendations, the authors suggest:

  • reforesting abandoned or unproductive agricultural lands and enforcing conservation policies,
  • making land-use policies more specific and relevant to local areas,
  • identifying technical opportunities to increase yields sustainably on existing land, and
  • identifying areas that should be preserved or restored as well as areas of “lower-opportunity-cost lands” if expansion cannot be avoided.

These types of changes could have multiple benefits, including guiding funders toward promising strategies, reassuring agricultural producers they can find ways to adapt to climate changes on their current lands, and helping to further quantify the impact agricultural and preserved lands have on greenhouse gas emissions.

Just as farmers will need to adapt from season to season as climate change alters food systems, policymakers, too, will need to be open to monitoring, updating, and innovating over time. This requires allocating resources to determine whether predictions were accurate and whether policies are having the intended effects.

“A holistic approach that looks at food security from many perspectives is needed to ensure that we can feed a growing population on a hotter planet,” Searchinger concluded.

Creating a Sustainable Food Future: A Menu of Solutions to Feed Nearly 10 Billion People by 2050 was published in July 2019 by WRI in partnership with the World Bank Group, the U.N. Environment Programme, the United Nations Development Programme, the Centre de cooperation internationale en recherche agronomique pour le développement, and the Institut national de la recherche agronomique. This report was funded by the Netherlands Ministry of Foreign Affairs, Royal Danish Ministry of Foreign Affairs, and Swedish International Development Cooperation Agency