More productive farming lowers global emissions

A new study shows that increasing production on farms and reducing emissions can go hand-in-hand, with researchers finding that improved farm productivity has been the driving force in keeping greenhouse gas emissions from agriculture in check.

In the study, published Jan. 16 in Science Advances, researchers from Cornell and the European Commission's Joint Research Centre analyzed worldwide data from 1961-2021 to determine why agricultural production has far outpaced emissions. They found consistently that farmers' ability to produce more output per unit of input, or higher productivity, was the main source of reduced emissions.

"There are environmental goals that you can achieve while increasing productivity," said first author Ariel Ortiz-Bobea, associate professor in the Dyson School of Applied Economics and Management, in the Cornell S.C. Johnson College of Business. "We have to take a harder look at the cheapest, most efficient way of achieving those goals - and what we've seen in the past is that increases in productivity have also been the driving force for keeping emissions in check."

Since 1961, both global agriculture production and emissions have increased, but productivity, growing 270%, has outpaced emissions, which have risen 45%. Still, agriculture and other land uses account for approximately one-fifth of human-generated greenhouse gas emissions, with reductions needed to slow global warming.

Ortiz-Bobea's findings have implications for policymakers and for the direction of research and development (R&D) in agriculture, both in the U.S. and globally.

"If you look at U.S. agricultural productivity, for instance, we're starting to see a taper that finds its origins in the stagnation in R&D funding over the past four decades," said Ortiz-Bobea, who is also a faculty fellow at the Cornell Atkinson Center for Sustainability. "In a world with very limited resources, we need to better think about how we can design an R&D policy where we're setting clear goals for what we want to achieve. Are we trying to produce more? Are we trying to reduce emissions? Can we do it both ways?"

Ortiz-Bobea conceived of the study last summer, when he was conducting research at the Joint Research Centre (JRC). He and co-author Simone Pieralli, agricultural economist at the JRC, saw that studies analyzing the "decoupling" of agricultural production and greenhouse gas emissions - or how to increase ag production without raising emissions - did not explicitly consider the role of inputs and were often not connected to economic concepts and metrics.

"Calories are important, but when you think about national statistics, they're not measuring calories, they're measuring value," he said. "How much value do we produce? How much capital, materials and labor do we use in the process? And how much greenhouse gasses are emitted as a byproduct? We wanted to bridge these ideas and bring them into the same framework."

Ortiz-Bobea and Pieralli used USDA data on agricultural inputs and production from every country and emissions data from the Food and Agriculture Organization of the United Nations. They plugged the data into an equation that factored in farms' inputs and outputs, emissions per unit of input, and output per unit of input to determine what had the greatest impact on emissions.

The study's results don't pinpoint specific practices or policies that led to increased productivity and reduced emissions, but the researchers found evidence that technological advances that improve land efficiencies - such as improved fertilizers and seeds - play a larger role in reducing emissions than efficiencies in labor.

"It appears that the direction in which the technology has been changing, at least globally, might actually help decarbonize," Ortiz-Bobea said. "But we need another model to really get to the bottom of the trade-offs and to identify an ideal direction for technological change. We don't know exactly, but we wanted to put our finger on the different directions policies can push."

Ortiz-Bobea said the study is part of a shift in his work toward research that can inform policy, especially when it comes to innovation and technology in the ag sector.

"We want to reduce emissions, we want to increase output - we have these multiple balls in the air, but how do we weight them?" Ortiz-Bobea said. "And at this juncture, we don't want to take our eyes off any single ball."

Funding for the study came from the USDA.