Harvard-West Africa collaboration probes climate adaptation in Gulf of Guinea

When he visits coastal villages outside Accra, John Kusimi, a geographer at the University of Ghana, says residents have no doubt what is causing their beaches to vanish, their villages to flood, and their livelihoods to wither.

“You don’t need anyone to tell you it’s climate change. Local people have their own ways of measuring the changes, which they attribute to climate change. Most people are adapting on their own, without support,” Kusimi told an interdisciplinary and international team of researchers at a Harvard University workshop in early December: “Resilient Coasts: Sustainable Frameworks for Climate Adaptation in the Gulf of Guinea.”

The workshop brought together members of an ambitious research cluster sponsored by the Salata Institute for Climate and Sustainability to discuss fieldwork in Nigeria, Ghana and Côte d’Ivoire. By pairing climate scientists with economists and landscape architects, the cluster is addressing physical and economic adaptation in areas with limited government capacity.

Sönke Dangendorf, a physical oceanographer at Tulane University who quantifies changes to sea levels globally over the last century, opened the workshop with a keynote address stressing that the rising seas can be slowed, but not stopped: “With the greenhouse-gas emissions we have already put into the atmosphere, we have committed to a multi-century sea-level rise, which means we need to adapt.”

One of the cluster’s goals is to build a vulnerability index to predict damages from storm surges in densely populated coastal cities. But the paucity of tidal gauges and other observational data across the continent limits the ability to model these expected changes.

“Africa is lagging behind in terms of data,” said Rebecca Berkoh-Oforiwaa, a Salata Institute fellow, who is bridging physics and data analysis to recreate missing sea-level data from Senegal to Mozambique. “Our reconstruction is providing information about the past, to understand the present and to help inform policymakers’ adaptation strategies.”

The effects of climate change are not limited to the coasts. Seasonal rainfall patterns are growing unstable, hurting the cocoa farms that are an economic mainstay in Ghana and Côte d’Ivoire, while flooding traditionally dryer regions in the north.

Peter Huybers, chair of Harvard’s Department of Earth and Planetary Sciences, observed that in 2024 a globe-circling, equatorial band of rain called the Inter-Tropical Convergence Zone (ITCZ) had moved further north than ever before, part of a multi-year shift with implications for agriculture and food security.

“We are trying to understand the migration of the ITCZ so we can better predict rainfall,” Huybers said. “Developing sustainable agricultural practices further north depends on knowing what that future rainfall is going to look like and if the changes to the ITCZ are just an anomaly.”

Cocoa growers, he added, “need a deeper understanding of how climate change is going to influence the patterns of rainfall if they are to invest in the future.”

Hell or high water

The change to rainfall patterns and thus to a major commodity like cocoa illustrate how climate change is impacting large populations. Exports from Ghana and Côte d’Ivoire, the world’s largest producers, fell more than 50 percent this year.

For some populations, the response will be migration, often to cities that are already creaking under aging and limited infrastructure.

The world is “very, very unprepared,” said Satchit Balsari, Associate Professor in Emergency Medicine at Harvard Medical School, pointing to the myriad risks. “We can’t prevent this. People will move. It’ll be untenable to stay where they are, and people will move. But when they move, we have no absorption capacity in our current systems. We have healthcare systems that are either nonexistent or already very stressed.”

The Ivorian village of Azuretti, for example, situated on a sandbar just a few hundred feet wide, is rapidly eroding.

“In Azuretti, they tell us, ‘We are ready to relocate.’ But it is a sizeable community, so they can’t just take their stuff and go. They’re waiting for the government to facilitate,” said the cluster’s principal investigator, Emmanuel Akyeampong, Ellen Gurney Professor of History and Professor of African and African American Studies at Harvard.  

Akyeampong is leading outreach to help West African governments develop durable adaption strategies in situations as extreme as Azuretti’s and for areas where residents hope to remain in situ.

In parts of Nigeria, people have been building their homes on stilts among lagoons and estuaries for generations. Now, in Bariga, at the edge of the Lagos lagoon, residents are making their homes higher as the waters rise, seeking to hold onto their land and their communities, said Mokolade Johnson of the Department of Architecture at the University of Lagos.

“They’ve adapted a lot to keep their place, which is most important for them. I call this anticipatory architecture. We know the water will rise; the surge is coming. The question is, ‘Can I build a little bit above it while I maintain my space?’,” said Johnson, noting that local builders have determined which types of timber withstand the waters longest.

“The local exchange of [knowledge] is helping them survive. I think we should encourage this alternative,” he said, calling for more research into homegrown adaptation: “Are we ready to consider an architectural framework that is reflective of local peculiarities? What happens in New York or Boston’s waterfront is not what happens in the Lagos waterfront.”

Another form of adaption the cluster is studying is economic, with implications for food security.

Millions of coastal residents in all three countries depend on fishing for their livelihoods. But stocks of small, pelagic fish – the fish that swim in the upper layers of open ocean and can be caught with nets cast from artisanal canoes – have fallen sharply in the last generation. Landings in Ghana have dropped 90% since 1992. Warming waters are causing fish to move away. Overfishing is also a problem; as is corruption, with officials turning a blind eye to illegal Chinese trawling in territorial waters.

Robert Paarlberg, an Associate in the Sustainability Science Program at the Harvard Kennedy School and Emeritus Professor of Political Science at Wellesley College, is studying how income diversification may help fishing communities adapt. In a survey, Paarlberg found 90% of fishing households in Ghana said their children would not be able to depend on fishing in the future. Some of these families are turning to vocational training pilot programs underwritten by foreign aid.

“I don’t think denial and delay is the future. Fishing communities are into a kind of improvised income diversification,” he said. “A policy-led labor shift out of fishing through vocational skills training – I think that should be the future.”

Surfacing solutions

As the costs of climate change swell, countries in the Global South are stepping up calls on the developed world – which has historically emitted most planet-warming greenhouse-gases – to pay compensation through a UN-managed vehicle known as a “loss and damage fund.”

The magnitude of the challenge, and the stories of loss, can be disheartening. But cluster members know their efforts are useful to local officials lacking the resources to make a case on their own.  

“With this research, West African countries now can argue, ‘Here’s what we face because of your emissions’,” said co-investigator Jerry Mitrovica, a geophysicist who studies the causes of sea-level rise throughout history as the Frank B. Baird, Jr. Professor of Science at Harvard. “When we talk about loss and damage, much more realistic damage assessments are now at our fingertips.”