Perspective  |  February 7, 2024

Room to grow: Identifying the best opportunities for improving crop yield

by James Gerber

The global food system isn’t broken, yet it needs fixing. 

Agriculture is vital: It produces food for all of us, provides employment for over a billion people, and is central to many developing economies. It also is under a LOT of pressure: In the years ahead, it will need to meet growing demand while minimizing its environmental footprint and coping with a changing climate. If we improve yields on current farmlands, we can meet these needs without more land clearing – a huge contributor to climate change – and even allow some land to return to a natural state. 

Technological improvements, from improved farming machinery, to readily available fertilizers, to the hybrid seeds of the Green Revolution, to computer-assisted modern farming technology, have dramatically increased productivity in the past. But how much more can yields be improved? And where?

A study my colleagues and I recently published in the journal Nature Food examines this question through the lens of the “yield gap.” The yield gap is the difference between the per-acre or per-hectare crop yield farmers *could* obtain (the “yield ceiling”) and what they *do* obtain (the “actual yield”). Yield gaps aren’t necessarily a bad thing if it means that improvements are coming faster than farmers can apply them. 

Take maize in the United States, for example. The yield ceiling has seen steady increase, thanks to research into improved cultivars, inputs, and farming technologies. The actual yield is steadily increasing as well, showing that farmers are adopting new technologies and practices at about the same rate they’re being developed, though with a bit of a lag.

Abrupt changes in yield gaps due to changes in the trajectory of the ceiling or the actual yield, however, can signal that something needs to change. 

For example, these graphs show yield of two European grain crops stalling out around 2000:

From these graphs alone, the two seem similar. But when we add the yield ceilings, it’s evident that their situations are very different:

In Italy, maize yields have dropped due to the European corn borer, so the gap increased as the yield ceiling grew due to the development of GMOs that resist the insect (and that aren’t allowed in Italy). In France, by contrast, both the actual yield and the ceiling stalled for barley, suggesting a need for investment in new technologies. 

In our paper we identify three types of yield gap trends: “Stalled Floor” (like maize in Italy) “Ceiling Pressure” (like barley in France) and “Steady Growth” (like maize in the U.S.). Each suggests a different policy intervention needed to improve crop yields. Stalled Floor indicates that technology to improve yield exists, but farmers are not applying it. Here, philanthropists, NGOs, and businesses may wish to focus on supplying seeds or credit or education to farmers, or changing legislation. Ceiling Pressure situations, on the other hand, call for investment in improving agricultural technologies. Steady Growth indicates a healthy balance between investment in agricultural technologies and diffusion of new techniques, along with appropriate support, to farmers.

We found that these archetypes are distributed very differently across different crops and regions (click to expand maps):

Rice and wheat (which feed people) are at risk for yield stagnation, whereas maize (which feeds cars and cows, but in most places is not destined for food) has plenty of room for yield growth. This reflects the unfortunate reality that food security has not always been a priority for crop improvement. A more optimistic interpretation, though, is that the type of agronomic investment that has driven maize yields is possible for rice and wheat.

What does this all mean?  By identifying the various kinds of yield gaps and where they occur, we are providing information that can be used to target investments appropriately,  improving agronomic technology when yield gaps are closing, or pressing for change in regulations or market support or extension services that could best help farmers achieve higher yields where they are falling behind. This will help improve the global agricultural system, in turn providing gains for climate, environment, food security and farmer livelihoods.

Press Contacts

If you are a journalist and would like to republish Project Drawdown content, please contact

More Insights

Video  |  February 27, 2024
The climate solutions worth funding – now
There’s no question about it: We have all of the solutions to climate change we need. But which solutions should we deploy, and when and where should we deploy them, to have the biggest impact in the least amount of time?  In his latest TED Talk, Project Drawdown executive director Jonathan Foley presents the Drawdown Roadmap, a science-based framework for identifying the best solutions to use at the right time and in the right place to address climate change while improving human well-being and providing other benefits as well.  From emphasizing emergency brake solutions to elevating the importance of time over tech, the talk is sure to inform and inspire you as much as it did the live audience of executives, scientists, policymakers, artists, activists, innovators, and others at TED Countdown Summit 2023 in Detroit. Speaking to an invitation-only audience, Foley unpacked the Roadmap’s signature approach to allocating climate solutions funding to maximize returns on investment: 1) start with solutions that reduce greenhouse gas emissions immediately; 2) deploy currently available solutions rather than count on new technologies to do the job later; 3) home in on geographic hot spots; and 4) prioritize solutions that also boost human well-being. Watch the video now by clicking on the image above – then share with colleagues and others who might benefit from this important message.
Read more
Perspective  |  February 2, 2024
Matt Scott presenting at the 2024 Great Northern Festival
We can’t end the climate crisis without “passing the mic”
by Matt Scott
If there’s one thing I’ve learned through my career as a storyteller, it’s this: Everyone has a story, and those stories have power. But in a society that often prioritizes science, data, news of the problem, and traditional voices over personal narratives, this essential truth is easy to overlook. I’d always been drawn to the stories my dad, Moses Scott, would share about growing up as a Black child in Civil Rights Era Virginia. He faced countless obstacles and, in his resilience, was my role model. He showed me that even when people want you to shrink yourself, you have to keep going, and I’ve always been motivated by his courage and fire to prove everyone wrong. When my dad passed away on March 8, 2017, he became the heart of my story, and the reason why I’ve dedicated my career on “passing the mic” to the changemakers who often go unheard. I’d long known that his story and the ways it influenced me were significant. However, it was his death that made me acutely aware that many of us – particularly those from Black and Brown communities – never have our stories told. That’s a key reason I share my dad’s story far and wide to this day; his story, like those of so many others that often go unheard, is full of insights that not only inspire and inform me but that have the power to motivate others. A couple years before his passing, I interviewed my dad about his story. “The way I see my life is taking lemons and making lemonade.” He continued, “That’s what, for me, Prince Edward County was.” The Story of Prince Edward County In 1959, the state of Virginia adopted the anti-integration policy of massive resistance. This blocked the desegregation of public schools ordered by the United States Supreme Court following Brown vs. the Board of Education. Until then, Black students and White students almost entirely attended separate schools, with Black students, including my dad, relegated to substandard conditions. When Virginia’s government closed the schools, nobody – including my dad, who was 16 at the time – would have imagined that some 1,700 students would be left without a formal education for five years. Consider the negative impacts of distance learning due to the COVID pandemic; now imagine learning being put entirely on hold for five years. “When we found out the schools were closed, I wasn’t too concerned,” my dad shared with me in an interview. “I was very happy to get another two months not to study and do whatever I wanted. But then, when it went beyond that… I missed school. School was where I competed, where I’d show that I was just as good as anybody and better than most. That outlet was gone.” In 1960, when given the option to become one of only 70 students to finish school living with complete strangers hundreds of miles away, my dad jumped at the opportunity. By the time the schools reopened, my dad, at 21 years old, was on his way to graduating from Howard University. In the following years, he would serve as a military captain, graduate from Harvard Business School, start a family, and launch his own business. Black history, my history, is filled with these stories of resilience, triumph, and joy. Still, I witnessed our predominantly White community discount my dad, overlooking his real-life superpowers and story. This was nothing new for him. Growing up, my dad cleaned the homes of wealthy, White community members who didn’t see his full potential. He told me, “Everything in that environment motivated me… Ms. Marshall, silver hair, about 80 years old. I used to go up the hill and I’d clean her house. One day, I must’ve been about 9 and she said to me, ‘Moses, if you learn how to make bed good, you might be able to get a good job at a hotel’…That made me mad, too. ‘No way!’ That’s what I said to myself, and this all helped me to be motivated.”  Even 60 years later, I could feel the emotion in his voice. His story taught me that challenging circumstances present us with a choice, a chance to take lemons and make lemonade.  The Stories We Need for a World in Crisis I can see strong parallels between my dad’s story and the treatment of people at the frontlines of the climate crisis. I’ve realized that even when you know that you have something valuable to contribute, people don’t always see your power.  As a young, Black, LGBTQ person, I have often been the only one from any of those demographics in the room in climate change conversations. Scientists, engineers, policymakers, and even storytellers, who are predominantly White men, have shaped the dominant narrative, discourse, and decision-making about climate. That is problematic. To end the climate crisis, conversations must include underrepresented problem-solvers who have thus far been overlooked in popular climate dialogue. We need narratives that center Black and Indigenous communities, communities of color, and others, who already bear the brunt of climate change and understand what just solutions look like. New narratives are critical to shine a light on untapped power.
Read more