International Agreements - Global Yield Gap Atlas

UNL Researchers Lead International Yield Gap Project

As the world’s population explodes to an estimated 9 billion people by 2050, farmers face the daunting challenge of making the most of every acre of suitable land while preserving the environment.

Increasing yields on existing farmland obviates turning to rainforests, wetlands and other unsuitable land.

“The critical question is: Where in the world do we have existing farmland with the capacity to produce much higher, stable yields?” said Ken Cassman, Robert B. Daugherty Professor of Agronomy at the University of Nebraska–Lincoln.

To answer that question, Cassman and an international research team are developing a tool to identify areas around the globe where significant gaps exist between actual and potential yields for different crops. Yield potentials vary widely and often are difficult to measure.

Unlike other efforts to estimate yield potential, the team’s Global Yield Gap Atlas uses a bottom-up approach. Working with colleagues at Wageningen University in the Netherlands, the team is recruiting agronomists worldwide to identify key agricultural areas and collect data about local conditions and farming methods. These data are then scaled to the national, regional and global levels.

They also are developing the necessary methodology, such as accurately converting short-term weather data into long-term patterns and scaling up local yield estimates. All information and methodologies are shared on the new public website,

“The beauty of this project is that it is a global project but with local relevance,” said UNL agronomist and co-investigator Patricio Grassini. The atlas will estimate global yield trends and food security and also help individual countries identify production potential to better strategize resource allocations and trade opportunities.

Agricultural economist Justin van Wart brings a large-scale perspective to the project. His doctoral work for Cassman included developing methods to scale local data to regional and global levels. Now, as a postdoctoral fellow, the Nebraska native finds himself in a new country almost every month, presenting his methods and helping to build collaborations.

“It’s amazing to work with internationally renowned agronomists,” van Wart said. “It’s kind of surreal to be shaking hands and talking directly with the person whose paper I was highlighting for a report just a few months ago.”

With a $2 million grant from the Bill & Melinda Gates Foundation, the team is working in India, Bangladesh and 10 Sub-Saharan African countries. Grassini also has developed collaborations in Argentina and Brazil with funds from the University of Nebraska’s Robert B. Daugherty Water for Food Institute.

Securing food for the future requires accurate information and decades of planning, said Cassman, who also chairs the Independent Science and Partnership Council, which advises the Consultative Group on International Agricultural Research, or CGIAR, on the scientific merit of global research projects. “We need to do a better job than we have in the past, and that’s what the Global Yield Gap Atlas will do.”

From left, postdoc Justin van Wart with UNL agronomists Patricio Grassini and Ken Cassman.
From left, postdoc Justin van Wart with UNL agronomists Patricio Grassini and Ken Cassman.