Data from Brazil’s National Institute of Meteorology show how the host city for COP 30 is becoming hotter and drier -tracking a trend that already threatens key crops like açaí and jeopardizes income and livelihoods for communities in the region.

By Anna Peres (O Liberal)

Ruy Barata, a Brazilian poet and songwriter from the North and the Amazon region, once wrote verses that became an ode to riverside life. “This river is my street. Mine and yours, mururé,” he writes in the opening stanza – lines that elegantly capture and celebrate the traditional way of life of communities living along the Amazon’s riverbanks, grounded in coexistence and profound respect for the rivers and forests entangled with them. For those unfamiliar, mururé is the local name for several species of aquatic plants common in waterways throughout this part of Brazil.

Yet the life that inspired such poetry is now under threat. This is evidenced on Combu Island, just a ten?minute boat ride from Belém – the city set to host the 30th United Nations Climate Change Conference (COP30) this November. The island stands as a poignant example of the risks posed by unregulated human activity, biodiversity loss, and shifting climate patterns, as shown by this collaborative investigation involving Latin American journalists and scientists, led by Brazil’s Serrapilheira Institute and the Latin American Center for Investigative Journalism (CLIP), examining how damage to Amazonian biodiversity interrupts vital environmental services the region provides.

Surrounded by the muddy waters of the Guamá River – so named for their brown hue – Combu is one of the 42 islands that make up Belém’s insular region. The island, about 1,500 hectares in area, is regularly flooded by tidal waters. As a result, all its buildings – houses, restaurants, lodges, schools, and even health posts – are built on stilts or wooden pillars, often offering scenic river views. For local riverside residents, the river is more than a transport corridor; it is a living territory, essential to their survival and identity.

Some 1,500 people live there, according to the Pará State Institute for Forestry and Biodiversity Development (Ideflor?Bio), the state agency responsible for the Environmental Protection Area (APA). Longtime inhabitants serve as living witnesses to the profound transformations the island has undergone in recent years.

Prazeres Quaresma, 56, is one such resident. Her family has lived on Combu for at least three generations. Her maternal grandfather arrived in 1914, at the close of the Amazon’s rubber boom, and began cultivating cocoa. Later, following Brazil’s cocoa crisis, he switched to açaí. In the 1980s, her father, José Anjos, founded one of Combu’s most iconic restaurants – Saldosa Maloca – which is now managed by Prazeres.

“I always say I feel an intimacy with Combu. Most of my family is here. So we worry about the future of this island,” the business owner says. In addition to Saldosa Maloca, known for dishes featuring Amazonian fish like tambaqui and piraíba (commonly called filhote), Prazeres also owns a small farm on the island. Over the past two years, fruit production there has been compromised by climatic factors such as rising temperatures and the droughts of 2023 and 2024. “It was terrible. We always think, ‘We had an intense drought this year, but next year will be better.’ Then the next year is worse. And we never prepare for the worst – we always expect improvement, we believe it will get better,” she laments.

The effects of the climate crisis, however, go beyond the impact on the production of açaí, cocoa and cupuaçu. “I remember that a few years ago, when we went to bed here on the island, we had to cover ourselves because it was cold. Today, we sleep completely uncovered and still having to turn on the fan. Can you imagine that? How much it has already increased (the temperature), how much the changes are happening and how much they are affecting our lives”, says Prazeres.

Belém: hotter and drier

What Prazeres feels and observes in Combu’s vegetation is now backed by science. Over three months, the team responsible for this article worked with scientists from the Quantitative Ecology Training Program at Instituto Serrapilheira. Researchers Maria Luiza Busato and Luís Cattelan extracted and analyzed precipitation, temperature, and humidity data for Belém from two National Institute of Meteorology (Inmet) stations in operation from 1981 through 2024.

Their analysis reveals a city becoming increasingly hot and dry since the early 1980s. Over the past 40 years, average temperatures rose by 1.32?°C, while relative humidity – the ratio between the moisture in the air and the maximum humidity that could exist at a given temperature – dropped by 2.64%. In the driest season, the so-called Amazonian summer from June to November, these changes intensify: temperatures increased by 1.86?°C, and humidity fell by 5.3%.

For plants such as açaí – which many riverside families rely on as a key food source and income generator – this climatic shift is proving devastating. Preliminary data from a study by the Brazilian Agricultural Research Corporation (Embrapa) in Eastern Amazonia indicate a 15–20% decline in non?irrigated açaí yields from floodplain and igapó areas, and up to a 40% drop in irrigated, upland açaí production in Pará for 2024.

“Particularly during the driest periods, there were many signs, in Embrapa?monitored plantations, that something was excessive, and it was air temperature,” explains Embrapa researcher Alessandro Carioca, specialist in Meteorology of Forest and Agricultural Ecosystems in the Amazon.

Carioca tracks açaí, cocoa, cupuaçu, and palm oil crops in the municipalities of Tomé?Açu and Moju in northeastern Pará. He noted that maximum daily temperatures repeatedly exceeded long?term averages. “The signals became more evident when those working with these crops began reporting that açaí flowers were being ‘aborted’, fruits were not filling, plant vigor was declining, with leaves scorching and dying,” he detailed.

What’s unfolding in northeastern Pará is also playing out 200 kilometers away in Belém. “Last summer, many trees died – cupuaçu, peach palm, guava… they dried out completely, from fruit right through to entire trees,” says artisan Silvia Rosa, 40, describing losses on her plot and those of her in-laws adjacent to her home.

Dry and hot days

Silvia, who has lived on Combu since age five, produces bio-jewelry crafted from Amazonian leaves and seeds. Her long treks across the island in search of materials have also changed with the climate. “Long ago, when I went into the forest to collect seeds, I would come back covered in mud. Not anymore. It’s much drier now. So you can feel the difference – it is hotter and drier too,” she says.

Over the past year, 46 of Pará’s 144 municipalities experienced more than 150?days of extreme heat. Belém and Melgaço, on Marajó Island, led the nation in the number of consecutive extreme heat days, according to analysis from Brazil’s National Center for Disaster Monitoring (Cemaden), based on satellite data from the National Institute for Space Research (Inpe).

According to the same data, Belém endured 212 consecutive days with temperatures reaching 37.3?°C – up to 5?°C above the average maximums recorded over the past decade. It was an unprecedented record, even for a city long known for constant high temperatures.

Recurring Droughts Ignite Water?Security Alarm  

High temperatures and reduced humidity have been compounded by drought over the past two years. In both 2023 and 2024, the Amazon endured extreme dry spells with precipitous river-level drops – effects tied to an intense El Niño event, which warms Pacific waters, disrupts global weather patterns, and influences climates worldwide.

In Belém, one visible consequence may have been the prolonged intrusion of saltwater into the Guamá River. “It always happens during summer. The river’s water turns greenish and brackish. But before, it lasted a month or so. Last year, it was around three months,” says Prazeres. “In this estuary region, close to the Atlantic, when we experience intense drought and river flow decreases significantly, the ocean pushes further upstream,” explains biologist Vania Neu of the Federal Rural University of the Amazon (Ufra).

Risks to the açaí

Since 2023, Neu and researchers from seven institutions across Pará, São Paulo, and Rio de Janeiro have studied the estuary of the Pará River – which includes the Guamá River and Guajará Bay, waters that wash around Belém and its islands. “It is deeply troubling that when we look long?term and see extreme events like droughts intensifying – once occurring only every few years – they are now happening in back?to?back years,” she reflects. “This increased frequency, and rising salinity in these waters, causes profound water insecurity for those living here.”

Prolonged saltwater intrusion may also threaten açaí cultivation. A 2023 study by geographers Cristóvão Henrique Ribeiro da Silva and Raylene Cameli of the Federal University of Acre (Ufac) described similar developments in Amapá’s Bailique archipelago. In recent years, longer flood events, ocean encroachment, and reduced Amazon River flow led to saline contamination of freshwater – resulting in reports of local families harvesting salty açaí.

Droughts in the Amazon have grown more frequent since the 2000s. Between 1960 and 1990, seven droughts were recorded; in the past two decades, the region has suffered eight, four of which were deemed extreme: 2005, 2010, 2015–16, and 2023–24.

A Dual Emergency: Climate Crisis and Biodiversity Loss

Over the last decade, Combu Island has emerged as a tourist magnet for Belém. But with economic boom has come social, environmental, and cultural strain – largely due to inadequate regulation. Since 1997, the island has been designated an Environmental Protection Area (APA), intended to conserve biodiversity and guide human occupation toward sustainable resource use.

It was only this year – after repeated protests and mounting pressure from riverside residents – that the Pará State Institute for Forestry and Biodiversity Development (Ideflor-Bio), the state agency responsible for overseeing the Environmental Protection Area, began drafting a management plan for Combu. Human settlement, particularly along the banks of the Combu Stream – where most of the island’s bars and restaurants are concentrated – expanded dramatically following the arrival of electricity in 2011.

A March report from the Amazon Foundation for Support of Research and Studies (Fapespa) maps Combu’s ongoing transformation. Between 2002 and 2023, the island’s cleared land increased nearly tenfold – from 0.124 km² to 1.237?km² – while dense forest shrank by 6.26%. Human occupation soared 49-fold, from 0.010 to 0.491 km². Water bodies contracted by 30.67%.

Riverside resident and owner of one of the most traditional restaurants in Combu, Prazeres, who is also a tourism expert, defends community-based tourism as an alternative to the current occupation model. “It’s possible to bring economic development to the island without destroying it. Urbanization is not the right answer. I believe people visiting Combu should seek a forest experience,” she says.

She also expresses concern about elements of riverside identity that are disappearing amid the frenetic pace, such as bathing in the river and transportation in canoes, or cascos, as riverside residents commonly call them. “When we used to bathe in the river, especially as children, we would play hide-and-seek and tag… Today, that is no longer possible because of the speedboats that pass by at high speed. So the younger generation is losing this connection with the river.”

Silvia, a mother of two – a boy and a teenage daughter – who grew up playing in the river, no longer lets her children do the same, fearing accidents. For her, living in harmony with nature requires respect. “We must respect nature. By respecting it, we reap its benefits, and we can sustain ourselves from it.”

Three years ago, Silvia made the production of handicrafts and bio-jewelry her main source of income. She draws nearly all she needs from nature. For her, the relationship with river and forest is not one-way but built on stewardship and responsibility in resource management.

On each journey to collect leaves and seeds, she practices tutoring passed down from her father-in-law, a veteran açaí harvester. “Since he was little, he went into the forest. Here, our life revolves around açaí – so the kids start early, learning everything. He knows the forest, every seed, every leaf – what it is and what it’s for,” she explains.

Silvia and Prazeres – two Amazonian women rooted deeply in Combu – have raised their voices leading up to COP30, already dubbed “the Forest COP.” “I hope it’s not just another gathering of nations to talk about climate. Climate has already been talked about a lot. What we need now are measures to undo the damage already done. I hope this meeting brings effective solutions and not just speeches,” says Prazeres. That, she adds, is what all forest peoples seek.

This story is the result of a collaboration between Latin American journalists and scientists, fostered by Instituto Serrapilheira of Brazil and the Latin American Center for Investigative Journalism (CLIP), exploring together how damage to the Amazon’s biodiversity disrupts the various environmental services it provides to the continent.