A team from AidData is shown on the roof of the United Nations' Food and Agriculture Organization headquarters in Rome. From left: Sara Sayedi, Ariel BenYishay, Jessica Wells, Kunwar Singh, Rachel Sayers, Yuntian Bi and Katherine Nolan. (Photo by Sam Gruber)

The following story originally appeared as an online exclusive for the W&M Alumni Magazine. - Ed.

What can satellite imagery tell us about the best way to conserve water in Niger or how much fertilizer farmers should apply in India? Using geospatial analysis methods developed at William & Mary's AidData lab, researchers are helping to shape solutions to climate-related agriculture challenges around the world.

Over the past four years, AidData's GeoField initiative has assessed the effectiveness of projects such as irrigated rice farming in Bangladesh, sugarcane planting and soil erosion control in Nepal and sweet potato crops in Ethiopia. These evaluations are used to guide decisions about how to invest most effectively in economic development and conservation.

A team from AidData recently convened 120 international policymakers, researchers and nonprofit leaders in Rome to discuss progress made and strategies for the future.

Hosted by the United Nations' Food and Agriculture Organization, the meeting in Rome from June 1-3 follows smaller gatherings held at William & Mary in January 2025 and another in Paris later last year. The recent convening also marks the end of a four-year grant from the Gates Foundation for AidData and its partners, Mercy Corps and DevGlobal, that provided the majority of funds for GeoField.

"The convening celebrated how far the field has come in just a few short years, in terms of using new technologies and tools to tackle really difficult global problems," says Ariel BenYishay, a W&M economics professor and AidData's chief economist.

Many of the projects are located in sub-Saharan Africa and Southeast Asia, with a few in Latin America - areas where people's lives and livelihoods are increasingly at risk because of environmental changes such as drought, flooding and encroaching desert.

"Understanding which types of investments can help farmers become more resilient to climate change is the source of our motivation and urgency," BenYishay says.

In Niger, for example, the desert is continually extending southward, making farmers' livelihoods increasingly fragile. Conserving water there is paramount for growing crops. Using satellite imagery, AidData researchers are able to measure the effectiveness of a technique known as demi-lunes or half-moons - shallow, semicircular earthworks that retain moisture long enough for crops to take root.

Another GeoField project involves Precision Development, a not-for-profit research organization that's working with cotton farmers in India to apply fertilizermore strategically. The goal is to conserve fertilizer as a cost-saving measure while also reducing the environmental impact from nitrogen runoff, BenYishaysays.

Precision Development is promoting the use of leaf color charts that cotton farmers can use to identify which stage of development their plants are in and how much fertilizer to apply at that stage. While the organization had been relying on chlorophyll meters and reports from farmers, it was difficult to assess how well the efforts were working. AidData's team was able to provide a more comprehensive look by overlaying satellite data for the whole season.

"The impact we're trying to have by adding satellite data is how we can learn in ways that complement what the partner organization is getting from its ground-based data collection," BenYishay says.

In Rome, members of the AidData team and others presented papers that were submitted to a special issue of the Journal of Development Economics co-edited by BenYishay and Kunwar Singh, senior geospatial scientist and an affiliate faculty member at W&M.

With the grant period ending, BenYishay says that GeoField will seek new sources of funding. Meanwhile, the work will continue with core partners. Among those is the International Fund for Agricultural Development (IFAD), which was established in the 1970s to address global food crises and spans 92 countries. Last year, IFAD issued an 18-month, $450,000 contract for AidData to help conduct geospatial impact evaluations of irrigation projects the organization has been studying.

Papers written by W&M research faculty who made presentations at the Rome convening are also being incorporated into an open-access, online textbook set to debut by the end of the year. Titled "Geospatial Impact Evaluation in Practice," the textbook is co-edited by BenYishay and Singh and will be published by Taylor & Francis.

The textbook is another way of sharing knowledge and expanding the use of geospatial analysis. Students and development professionals will be able to not only learn geospatial methods, but also see how they're applied in specific contexts and practice using them through exercises that are included. Another partner organization, Agence Française de Développement, provided funding for the French translation of the textbook.

"We've brought together a community of practice that includes remote sensing and impact evaluation specialists, environmental scientists and people who work on designing agricultural improvement interventions," BenYishay says. "A big part of the GeoField initiative is taking all the methods, lessons and data that we've developed and using them on projects that are being funded by other donors."

For William & Mary students, working with AidData offers a chance to assist with research that produces tangible results.

Doctoral student Jacob Hall '22, who majored in geology as an undergraduate and enjoys computer programming, became a research assistant in 2020 after noticing an announcement from AidData research scientist Seth Goodman seeking students who could program in Python.

"I had no idea how to program in Python, but I emailed them anyway and said I could learn, probably," Hall says. Although unfamiliar with geospatial analysis at the time, they soon became hooked: "It was a whole new world to me."

Now pursuing a Ph.D. in computational geography, Hall is also working full time as a data analyst for AidData. In this role, they have traveled to Honduras and Ethiopia to train teams on the most cost-effective ways to conduct surveys to prove that crops such as coffee aren't being grown on deforested land - a requirement of trade with the European Union.

"The GeoField projects that we're working on are really interesting, because half of it is remote sensing, geospatial stuff that's more my specialty," Hall says. "But then there's this whole other aspect of what this actually means for the economics of a place. I think that's one of the more unique aspects of GeoField. It's able to combine those fields of data analysis and economics in very rigorous ways."

Tina Eshleman, University Marketing

• share by email
• share on Facebook
• share on X
• share on LinkedIn

• share by email
• share on Facebook
• share on X
• share on LinkedIn

Related Stories