Growing Resilience From the Ground, Up

Ugandan-born Geographer Catherine Nakalembe Links Satellites and On-the-Ground Monitoring to Help African Farmers Weather Extreme Events

CATHERINE NAKALEMBE STOOD shin-deep in the middle of an Eastern Ugandan river on a sweltering, blue-sky day in 2014, peering out from beneath her wide-brimmed hat as she surveyed the farmland before her. A geographical sciences assistant professor and expert in satellite remote sensing, she’d seen this field before—from space. Approximately 350 miles up, satellites could capture the patchwork tapestry of browns and greens that make up Africa’s agricultural landscape. But the images they beamed back couldn’t tell Nakalembe if the crop in front of her was maize or wheat.

As the Africa program lead for NASA Harvest, an international consortium commissioned by the space agency and led by the University of Maryland, those details were critical to her work. Without knowing the crop type, computer models couldn’t monitor how it will fare against a spike in temperature or a projected wet season, or inventory what’s growing in the region. So Nakalembe tromped across Eastern Africa’s small farms—often no more than three acres each—every July and August from 2010 to 2016 to document its fields.

“I walked so many miles, I was in such great shape,” she says. “It was time-consuming and so hard, but it’s what was needed.”

Much of Nakalembe’s own orbit, she says, has been shaped by fateful encounters, people and timing: from her journey to UMD to her path home to fight Africa’s food crisis. And as earth-circling satellites piled up growing mountains of data, she knew she couldn’t singlehandedly teach them to “see” African agriculture with her cross-country treks. It would take another chance event—and on a truly global scale—to literally drive her team to a solution.

“A lot of the things that have happened in my life are by chance,” she said. “But maybe the chances just add up.”

TWO YEARS BEFORE THAT WOULD HAPPEN, in 2018, two cyclones drenched the desert sands of the “Empty Quarter,” a barren expanse straddling Saudi Arabia, Yemen and Oman, awakening generations of locusts to breed and wage a ravenous campaign. Deafening swarms stretching to the horizon laid waste to crops and pastureland over six countries in East Africa, plunging the already food-insecure region into crisis.

Locust plagues and other extreme events, from floods to drought, have battered Africa’s agriculture industry for centuries, exacerbated its high rate of hunger and fueled economic and political instability. But this crop of airborne pestilence, which lasted until 2022, stemmed from irregular circulation and temperature patterns in the Indian Ocean likely caused by climate change.

Extreme events, which are expected to increase as global warming continues, deliver profound socioeconomic blows. According to the consulting group McKinsey and Co., agriculture is Africa’s largest economic sector, accounting for more than $100 billion annually and employing over half the continent’s workers. Meanwhile, nearly 800 million Africans— roughly 60% of the population—are food-insecure. In 2022, a person died every 36 seconds in drought-stricken East Africa.

Nakalembe’s work is central to UMD’s effort to advance the use of remote sensing and artificial intelligence (AI) to monitor and protect global food security. In Africa, she has established herself as a trailblazer: Over the past 14 years she has combined her geographical expertise with the demanding, often improvisational nature of field work to provide governments with the tools to know what’s growing where, and the ability to respond to and head off crises on a continent where deadly food shortages occur with numbing regularity.

“This research is about getting out in front of some of the worst events,” says geographical sciences Distinguished University Professor Christopher Justice, who has worked with Nakalembe since 2010. “And it’s about getting quick, actionable information to those who need it to minimize the impacts on the population. In this respect, Catherine’s grabbing the bull by the horns.”

The photo is by John T. Consoli

Published on Tue, 04/23/2024 - 11:00