Living with volcanic and coastal risks in Fogo and Brava

Summary

In Cabo Verde, and particularly on Fogo and Brava, the islands I study, I think we need to consider environmental, territorial and social changes together.

What are currently the most significant changes in the relationships between the ocean, natural environments and societies in the territory you study? Which seem most consequential in the medium and long term?

In Cabo Verde, and particularly on Fogo and Brava, the islands I study, I think we need to consider environmental, territorial and social changes together.

The first major transformation is, naturally, climate change, because it is progressively altering the relationship between island populations and the resources on which they depend. We are talking about rising mean sea levels, coastal erosion, changing rainfall patterns, increasing temperatures and changes that also affect marine ecosystems and fishery resources. In a country where much of the population and infrastructure is concentrated close to the coast, these changes are especially significant.

On Fogo and Brava, however, this climatic dimension is compounded by a fundamental characteristic: these are active or potentially active volcanic territories, where society lives permanently with geological processes operating on timescales very different from human ones.

On Fogo, the most recent eruptions, in 1995 and 2014-2015, showed us very clearly how, in just a few weeks, the landscape, access routes, economic activities, housing and communities' relationships with the territory itself can be profoundly altered.

The situation on Brava is different. No historical eruptions have been documented since settlement, but the geology shows relatively recent volcanic activity, and seismicity is one of the most important indicators of the island's geological dynamics. Seismic crises periodically remind the population that this is an active geological system.

In the medium and long term, I consider three processes particularly consequential: climate change and the transformation of the coastal zone; growing pressure on limited natural resources; and the need for societies to adapt continuously to natural risks, including volcanic, seismic and slope-movement risks. In my view, the essential point is to understand that, in these small island territories, the ocean, geology, climate and society cannot be treated separately.

How do these changes redistribute vulnerabilities, resources and land uses? Which groups, activities or ecosystems benefit, which become more exposed, and what choices or conflicts result?

These changes do not affect all people or territories in the same way. Coastal communities, artisanal fishers, farmers, economically vulnerable families and people living in areas exposed to natural hazards tend to have less capacity to adapt. In fisheries, for example, changes in the distribution of marine resources have forced fishers to travel farther or into deeper waters, increasing costs, navigation time and occupational risks. On land, there is also competition between uses: agriculture, housing, nature conservation, resource extraction, infrastructure and tourism.

On Fogo, this relationship is particularly interesting because the area at greatest volcanic risk is also a territory of enormous agricultural, scenic, scientific, cultural and tourism value. Chã das Caldeiras is perhaps the clearest example of this apparent contradiction. People stay and return after volcanic eruptions because the territory offers resources, identity, economic opportunities and very strong social and cultural ties. Public policies therefore cannot think solely in terms of a "dangerous territory" versus a "safe territory". We need to understand why people choose to live in these places.

On Brava, we find a different reality: a small island strongly constrained by insularity and accessibility, with active volcanism but no historical eruptions, steep slopes and vulnerability to earthquakes and mass movements. This raises a central planning question: how can we conserve what has natural and scientific value without preventing people from using the territory to sustain their livelihoods?

The challenge is to find forms of development in which conservation also generates local opportunities.

Drawing on your fieldwork and research, which idea or experience that remains insufficiently heard should, in your view, contribute more to international debates and public action on the ocean, nature and societies?

One idea I consider important is that small island territories should not be presented solely as vulnerable places. Cabo Verde, as a small island state, undoubtedly faces very significant vulnerabilities. But islands are also extraordinary natural and social laboratories. On a relatively small territorial scale, they allow us to observe relationships between geological processes, environmental change, resources, human settlement, collective memory and the capacity to adapt.

My work on Brava particularly reinforced this perception. Despite its small size, the island has extraordinarily rich volcanic geodiversity. Within a very limited area, we find evidence of different phases in the island's formation, explosive volcanism, tectonic structures, erosion landforms and current processes that reveal an extremely complex geological history.

There is a second dimension that I consider even more important: the population is not merely a recipient of scientific information. People who live in these territories every day hold knowledge about water sources, slopes, paths, ground changes, earthquakes, places where particular events occurred and changes in the landscape over time. Scientific and local knowledge are, of course, not equivalent and do not necessarily use the same validation methods. But they can complement each other.

Cabo Verde can therefore bring this message to international debates: adaptation and risk reduction policies become stronger when science, institutions and communities produce knowledge together, instead of following a model in which experts produce knowledge and only subsequently communicate it to the population.

How do people on Fogo and Brava perceive and interpret volcanic and seismic risks in their everyday lives?

There is a very interesting difference between the two islands.

On Fogo, volcanic risk is part of historical memory and collective experience. Some generations directly experienced the eruptions of 1951, 1995 and 2014-2015, while others know about them through their parents and grandparents. The volcano is therefore not an abstract reality. It is simultaneously a threat, a territory, a resource and an identity. People have a very close relationship with it. They know the territory, interpret signs and draw on reference points passed down through earlier experiences. At the same time, this familiarity can lead to a degree of risk normalisation. Living beside a volcano for decades without another eruption can reduce the sense of urgency.

On Brava, the situation is different. Because there is no social memory of a historical eruption, volcanic risk is less tangible. Earthquakes, by contrast, are frequently felt and provide a much more concrete experience of geological risk. Seismic crises have precisely this effect: for a time, they turn a risk that may seem distant into an everyday concern.

It is therefore important to understand that people interpret risk through several sources simultaneously: scientific information, institutional communication, personal experience, family memory, observation of the territory, and also rumours and social media. Risk communication must recognise this plurality.

What role do memories of eruptions, family accounts and local knowledge play in preparing for and responding to geological crises?

They play a fundamental role.

On Fogo, previous eruptions constitute a kind of social archive of risk. Families remember where lava advanced, when particular signs began, which routes were used during evacuations, where the animals were, what they managed to carry and what they lost. These accounts do not replace hazard maps, instrumental monitoring or scientific models, but they help us understand the human dimension of the crisis. Some knowledge is unlikely to appear on a map: how long a family needs to remove its animals from a particular area; which older people require help; which alternative paths the community knows; and which family networks can accommodate displaced people.

On Brava, although there is no memory of an eruption, there is memory of earthquakes and seismic crises, including recent episodes that significantly changed risk perception. These memories also have an educational role. A child who hears parents and/or grandparents describe an earthquake learns that their territory is dynamic long before consulting any technical document.

It would therefore be extremely valuable to integrate oral history, community memory and science more systematically into education and risk reduction programmes. Preserving the memory of disasters is also a form of prevention.

How can the protection of geoheritage, the development of geotourism and the economic and social uses of volcanic territories be reconciled?

The first condition is to avoid treating conservation and development as necessarily opposing goals. Geoheritage will only be effectively protected in the long term if communities understand its value and benefit from its conservation. Geotourism can serve precisely this purpose: turning geodiversity and geological knowledge into education, recognition of a territory's value and local economic opportunities. But geotourism should not be confused with simply bringing more visitors to a geosite. A genuine geotourism model must involve scientific interpretation, site protection, participation by residents, training local guides, promoting local products, involving local authorities and distributing economic benefits within the community.

On Fogo, for example, the volcanic landscape can be connected not only with visiting the volcano, but also with agriculture, wine, food, biodiversity, architecture, culture, the history of eruptions and community experiences.

On Brava, extraordinary geodiversity can likewise provide an opportunity to develop small-scale tourism offerings linked to geological trails, landscapes, environmental education and science.

For both islands and for the country, however, it is essential to define carrying capacity, rules of use and protection for the most sensitive geosites. There is also an ethical question: communities living with real risks must not be turned into a kind of backdrop for disaster tourism. Visitors must understand that this is a living territory. The international approach to geoparks points precisely in this direction: using geological heritage together with natural and cultural heritage to promote sustainable development, education and risk reduction.

Where are the main gaps today between scientific knowledge, risk communication and institutional prevention capacity?

I would identify four main gaps.

The first is continuity in monitoring. Seismological and geodetic networks are essential, but they require maintenance, technological upgrades, specialised technicians and permanent funding.

The second is turning scientific data into information that civil protection services and the public can use. There is an enormous difference between saying that "seismicity has increased" and explaining to people what that means and what they should do.

The third gap is risk communication itself. When there is scientific uncertainty, a normal situation in volcanology and seismology, it is difficult to communicate without causing alarm while also avoiding minimising the danger. Trust must be built before crises. If the first communication between scientists, institutions and the community occurs during a crisis, we are already too late.

The fourth issue is institutional coordination. Scientific monitoring, civil protection, municipalities, universities, schools, health services, maritime operators and communities need to be brought even closer together.

Cabo Verde currently has a geophysical monitoring network with stations on both islands, but the presence of instruments does not remove the need to strengthen human and institutional capacities continuously. In my view, we should progressively move towards an approach that treats monitoring, communication, education and community preparedness as parts of the same system.

Which differences between Fogo and Brava should receive greater attention in the design of monitoring, planning and civil protection policies?

The first fundamental point is that we should not apply exactly the same risk management model to both islands.

Fogo has a very prominent central volcano, relatively recent historical eruptions and areas whose exposure to lava flows is well known. Its population also has direct or family memories of eruptions. On Fogo, it is therefore especially important to work on eruption scenarios, evacuation routes, settlement in the highest-hazard areas and the relationship between economic activity and volcanic risk.

Brava presents a different set of issues. The island has frequent seismic activity, geologically recent volcanism, evidence of explosive activity, diffuse gas emissions in some areas and very rugged topography. Beyond their direct risk, earthquakes can trigger slope instability and disrupt access routes. There is a further essential difference: Brava's insularity places much greater constraints on emergency response. A small island whose external connections depend heavily on maritime transport requires specific scenarios for evacuation, supplies, medical assistance and communication.

On Fogo, the strategy can therefore focus strongly on the relationship between the volcano, land occupation and eruption scenarios. On Brava, we need to think more explicitly in terms of a multi-hazard approach, integrating seismicity, volcanic potential, slope movements, gases, accessibility and isolation.

Finally, there is an important difference in social perception itself. Fogo has a memory of eruptions. Brava primarily has a memory of earthquakes. Risk communication and education policies must start from that difference.

In summary, science can produce shared methodologies, but risk management must be adapted to each territory. Fogo and Brava are geographically close and geodynamically related, yet their histories, vulnerabilities, accessibility, social perceptions and risk scenarios differ sufficiently to require distinct strategies.

Bibliographic information

Type

Article

Date

14 October 2026

Author

Vera Isabel Barros Alfama

Study Centre

ONS

Original language

English

Original document

PDF, 4 pages

Full text

Transcription of the original document

← All publications