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A new study, just published in the journal Nature Communications Earth & Environment, finds that severe droughts in the Amazon basin over the last two decades have led to longer periods of low water levels and triggered profound impacts on the local population. 

The severe droughts in 2005, 2010, and 2015-2016, in particular, not only drastically reduced water levels in a substantial part of the world’s largest river system, but also resulted in low water level periods exceeding 100 days, a month longer than expected. 

These droughts have major impacts on rural, remote Amazonian communities who heavily rely on inland water transport to access goods and services, reach urban centers, and maintain their livelihoods. The study concludes that during severe droughts, when such water transport is not available, nearly 50% of non-Indigenous localities and 54% of Indigenous villages in the Brazilian part of the Amazon basin are prone to isolation. These droughts also expose Amazonian communities to scarcity of goods, restricted access to healthcare and education, limited access to fishing and hunting sites, and other major impacts. 

“This is the new reality of the Amazon,” said Dr. Letícia Santos de Lima, researcher at the Institute of Environmental Science and Technology of the Universitat Autònoma de Barcelona (ICTA-UAB) and lead author of the study. “Scientists have been warning for years that the Amazon basin is facing a substantial increase in the frequency and intensity of extreme events due to climate change, on top of severe changes in its hydrological system due to deforestation and forest degradation. These past droughts as well as the most recent one, 2023-2024, are showing that the impacts on the ecosystems extend severely to the Amazon population.”

“The Amazon faces increasingly severe droughts due to global warming, with very real consequences for the communities that live there,” added Dr. Marcia Macedo, Woodwell Climate Research Center scientist and study co-author. “To better prepare for these extreme climate events, we need climate solutions that prioritize water resources alongside efforts to curb carbon emissions. This will be key for sustaining resilient ecosystems and communities in the Amazon and around the world.”

The paper states that “actions to cope with recent droughts in the Amazon have been reactive rather than proactive and grounded in preparedness and adaptation principles,” and calls for Amazon countries to “develop long-term strategies for mitigation, adaptation, and disaster response.” The authors also stress that any solutions to isolation must not also worsen the problem. For example, roads would not be an effective solution as they are a well-known driver of deforestation, which leads to changes in rainfall, contributes to a higher volume of sediments in rivers, and would impair navigability even further.

Using an interdisciplinary approach, researchers combined spatial analysis, methods from hydrology, and news media content analysis to deliver the first spatiotemporal assessment of cross-sectoral impacts of droughts in the Amazon basin.

Climate change was the center of the debate between rural producers, scientists, public authorities and indigenous peoples at the Symposium to Celebrate the 20th anniversary of the Tanguro Research Station, which took place in Brasilia from June 10 to 12. The event highlighted the dialogue between the groups as a key to socio-environmental and economic transformation in favor of a possible future for life on Earth.

Functioning as an open-air laboratory, the Tanguro Research Station is located in the city of Querência, in Mato Grosso, in the southeastern Amazon. It was founded by IPAM (Amazon Environmental Research Institute) in partnership with the company Amaggi and the Woodwell Climate Research Center in the United States. In two decades of existence, the results of this joint initiative add up to more than 180 high-impact scientific publications and bring together researchers from seven countries studying the environment and agriculture.

Ângela Conceição, president of FETAGRI, speaks on a panel at the event (Photo: Lucas Guaraldo/IPAM)

‘’The revolution in the countryside cost almost 50% of the Cerrado and 20% of the Amazon, this model is no longer sustainable, “said André Guimarães, executive director of IPAM. “It is necessary to ask questions to companies, as they will also have to adapt services to a new climatic condition,” he added. The director recalled that the assumption of the work at the Tanguro Research Station is to bring agricultural production closer to nature conservation.

The plurality of experiences and knowledge shared at the symposium was highlighted by Max Holmes, CEO of the Woodwell Climate Research Center, an institution that has been working alongside IPAM for thirty years.

“Bringing together this group of experts from science, civil society and from different places gives me hope and optimism. The challenge for all of us is to take forward the big ideas around the climate solutions discussed. Climate conferences are opportunities to continue to make progress on these incredibly urgent issues, which can only be solved in partnership,” Holmes said.

Balance

The meeting of different sectors around the socio-environmental and economic discussion comes at a time when studies show the loss of natural functions of tropical forests due to the global burning of fossil fuels, and, in Brazil, mainly due to deforestation, degradation and fire.

Ecosystem services, as the benefits produced by nature are called, maintain all forms of life, ensuring air quality and the availability of water and food, for example. They contribute to pollination, pest control and local climate regulation, providing adequate rain, humidity and temperature for agricultural production.

“How do we build a land use solution so that people understand that it is possible to reconcile forest with conservation, development with job and income generation from a better use of what we have already cut down? This is Brazil’s challenge. That is why we have sought a partnership with IPAM. That is why we created, in the State of Pará, the State Policy on Climate Change and the Amazon Now program,” said Helder Barbalho, governor of the State of Pará, present at the event.

Pará Governor HelderBarbalho and Minister Paulo Teixeira participated in the symposium (Photo: Disclosure/Agência Pará)

“We don’t know what the world will be like going forward, we just know it can’t be the same. We have a lot to learn and build with each other. Climate change is real and the producer realizes it, but if he does not feel he belongs in the conversation about what needs to be improved, it is difficult to engage,” said Juliana Lopes, director of ESG, Communication and Compliance at AMAGGI.

From 2022 to 2023, agriculture grew by 15.1%, influencing GDP performance, but still putting pressure on Brazilian biomes. The Tanguro Research Station develops studies to understand the influence of the forest on agriculture and vice versa, in order to subsidize environmentally and socially sustainable production and conservation strategies.

“Results of Tanguro’s research socialized with us are important to see new perspectives and develop agriculture, ensuring food security,” added ÂngelaConceição, president of FETAGRI (Federation of Agricultural Workers of the State of Pará).

Juliana Lopes endorsed the recognition: “The partnership with IPAM was the way that AMAGGI found, with researchers, to make an assessment of how we can ensure continuity in agricultural production, investing in the conservation of biodiversity and native areas.”

Knowledge generation

Storing half the carbon emitted on the globe, tropical forests provide climate stability. This stockpile capacity is being hampered by climate change caused by human activities. “Our challenge is to find ways to maintain that service and, at the same time, growth and prosperity,” said Woodwell Climate Research Center researcher Michael Coe.

And how to find an answer to this challenge? The solution may lie in nature itself. Data presented by Wayne Walker, senior scientist at Woodwell, shows that nature-based solutions have the potential to deliver 37% of the emissions reduction needed to limit global average temperature rise to less than 2°C. “Land is more than just a carbon store. We need to implement these solutions in a scalable way, ensuring capital flows with equity and sustainability,” he commented.

IPAM researcher Filipe Arruda pointed out that environmental disturbances have been occurring more intensely with climate change. “The impact on the habitat modifies the animal and plant species on site, changing everything from temperature control to pest control within the forest and in agricultural areas.”

Leonardo Maracahipes, coordinator of the Tanguro Research Station and researcher at IPAM, presented a study on the change in tree leaves in areas of intact forest and in those fragmented by agricultural activity. “The thickness of the leaf was greater in the area of agriculture, while the size of the leaf was greater in the areas of preserved forest,” he explained, demonstrating vegetation strategies to adapt to the surroundings.

In farming, the effects of nature are also the object of study: “We estimate a 6% reduction in soybean yield for every 1°C increase in temperature,” said Ludmila Rattis, a researcher at IPAM and the Woodwell Climate Research Center. On the positive side, when the forest is maintained, it helps in production. Bianca Rebelatto, a researcher at IPAM, recalled that 90% of Brazil’s agriculture is not irrigated and that forests protect crops against heat waves and reduce future climate challenges.

Scientists working at the Tanguro Research Station (Photo: Mitch Korolev/Woodwell)

Responses presented by the sectors to avoid more extreme events, reducing damage to the environment and promoting responsible ways of living include, in addition to sustainable production, the bioeconomy of natural products from the Amazon and Cerrado.

“Land use change and climate change have already increased the chances of a catastrophic fire in the Xingu by another 10%,” explained Paulo Brando, IPAM associate researcher and professor at Yale University in the United States. “About 16% of forests in the southeastern Amazon may burn due to these factors. Fire-degraded forests seem healthy from the point of view of remote sensing, but they are much more vulnerable to extreme events such as drought, which is what is happening in the Xingu and much of the region.”

According to Brando, the Xingu region is 2°C warmer due to increased deforestation and human pressure on the natural landscape. The Xingu Indigenous Territory functions as a local air conditioner, with 5°C less than monocultures and neighboring pastures, revealed a technical note produced by IPAM and the Woodwell Climate Research Center.

While the situation is not resolved, the peoples of the Xingu continue to struggle to produce. “We have the land, but we keep buying in the city. We, from the Xingu, are still studying how we can make production on a larger scale, “said Yuri Kuikuro, a master’s student in Ecology at INPA (National Institute for Amazonian Research). “It is necessary to bring young people to train, to use technology, to try to understand how to produce to maintain our culture. Add science to figure it out,” he concluded.

Survival

“First we have to think about surviving climate change: working in the collective, regardless of whether it is civil society, company or public power, for our physical and mental survival,” said Mauro O’ de Almeida, Secretary of State for Environment and Sustainability of Pará, present at the symposium.

The climate emergency alerts to the Amazon’s point of no return, also known as the tipping point, from which the biome would lose its natural capabilities and become a type of degraded ecosystem — a “zombie Amazon”. In the Cerrado, the reality also worries scientists, given that most of the biome’s remaining native vegetation is within private rural properties.

“It is common to hear that the world will end, but it has already ended, due to climate change, for the people who died in Rio Grande do Sul,” said researcher Ludmila Rattis, referring to the extreme climatic event of rainfall in Rio Grande do Sul this year. About 175 people died and 38 are missing. More than 2 million were affected by the floods, according to the Civil Defense.

In the Amazon, the Rio Negro drought in 2023 affected all 62 cities in the State of Amazonas and affected more than 600,000 people, also according to the state Civil Defense.

“The Xingu Indigenous Territory is also being impacted by climate change. Indigenous people have been talking about this for a long time and we are not taken seriously. These extreme events are affecting all sectors, so sitting at the table with partners who were once our enemies shows how we need to be united to change the scenario we have, “said Kaianaku Kamaiurá, partnership coordinator at OURS and coordinator of the Amazônia de Pé project.

The climate commitments of Brazil and the world, to be renewed and expanded until COP30 (United Nations Conference on Climate Change) in Belém, are the necessary measure to prevent the worsening of housing conditions on the planet and prevent more lives from being lost.

“First, that the world can accelerate the change in the energy matrix to stop emitting carbon dioxide. Second, pay for the maintenance of the forest and its recovery. In the past, I remember that agribusiness was against the climate debate, but not today: it has assumed an awareness that it needs the forest. COP30 will be the great political space in the Amazon to demand from the world attention for those who are preserving,” said Paulo Teixeira, Minister of Agrarian Development and Family Agriculture.

The Tanguro Research Station 20-Year Celebration Symposium was held by IPAM in partnership with the Woodwell Climate Research Center, Yale University School of the Environment, and Max-Planck-Geselschaft. Learn more about the Tanguro Research Station and how to donate on the website.

 

O céu se abre no momento em que nosso caminhão deixa o último trecho de estrada pavimentada. A Diretora do Programa de Água, Dra. Marcia Macedo, aperta os olhos para manter o foco no que consegue ver entre uma limpeza e outra do para-brisa. Em poucos minutos, nosso caminho se transformou de uma estrada de terra em um leito de rio de lama laranja brilhante, sulcado pela passagem de caminhões pesados que transportam soja das fazendas vizinhas.

Macedo desvia para evitar solavancos e depressões, mas logo há mais deles do que estrada plana. Nós nos preparamos para as poças, olhando pelas janelas salpicadas de spray laranja.

É uma manhã de segunda-feira, na estação chuvosa, nos arredores da Amazônia, e estamos indo para o trabalho.

A Estação de Campo de Tanguro fica a cerca de uma hora de carro de Canarana, a cidade mais próxima, localizada em uma região do Brasil às vezes chamada de arco do desmatamento. Há várias décadas, a agricultura começou a surgir na região sul da floresta amazônica, criando áreas retangulares de terras agrícolas na floresta primária. Na maior parte do trajeto, somos ladeados apenas por megacampos de soja ou pastos de gado.

Macedo, que realiza pesquisas na Tanguro desde 2007, lembra-se de uma época em que a viagem poderia ter sido marcada pela travessia do limiar das savanas florestais do Cerrado – Brasil – para a Amazônia. Agora, o desmatamento próximo à estrada obscureceu essa transição natural. Eventualmente, no entanto, tufos verdes exuberantes emergem da chuva e percebemos que estamos quase lá.

Desde a sua fundação em 2004, a Tanguro tem oferecido a pesquisadores de todo o mundo a oportunidade de investigar grandes questões sobre como as mudanças climáticas e o desmatamento estão afetando a Amazônia. Macedo e sua equipe vieram para estudar os córregos e reservatórios da Tanguro.

Paramos do lado de fora da estação de pesquisa, tirando as malas, embrulhadas em sacos plásticos de lixo, da caçamba da caminhonete. A assistente de pesquisa, Zoe Dietrich, segura vários componentes eletrônicos vitais no peito, levando-os para uma varanda coberta para protegê-los da chuva. A pós-doutoranda Dra. Aibra Atwood começa a retirar tubos de núcleo de sedimentos de uma pilha de equipamentos. As nuvens se dissipam e o dia de trabalho na Tanguro começa.

A Fundação

A decisão de se estabelecer na fazenda Tanguro causou polêmica na época.“Quase nos separou”, lembra o fundador da Tanguro, Dr. Daniel Nepstad. “Tivemos uma discussão que durou dois dias.”

Quatorze anos antes, Nepstad havia estabelecido o programa amazônico no Woodwell Climate (então Woods Hole Research Center) no estado do Pará, estudando a resiliência das florestas amazônicas durante as longas estações secas. Esse trabalho deu origem a um novo instituto de pesquisa com sede no Brasil – em 1995, Nepstad cofundou o Instituto de Pesquisa Ambiental da Amazônia (IPAM) em Belém para buscar ciência relevante para políticas que pudessem informar o desenvolvimento sustentável na Amazônia. A Woodwell Climate e o IPAM começaram a realizar experimentos de simulação de secas e descobriram que a floresta tropical, que há muito tempo era considerada imune ao fogo, perdia essa resistência durante secas severas. Para investigar as implicações disso, Nepstad percebeu que eles precisavam de um novo experimento em algum lugar na borda da Amazônia, onde é mais seco o ano todo.

Nepstad vinha passando cada vez mais tempo no estado do Mato Grosso, interessado pela expansão do cultivo de soja na Amazônia. Durante sua busca por um novo local de estudo, o Grupo Amaggi fez um convite extraordinário.

O Grupo Amaggi era, na época, o maior produtor de soja do mundo, e a soja estava rapidamente se tornando o inimigo ambiental número um, à medida que centenas de milhares de acres de florestas eram derrubados para expandir seu cultivo.

“Mas o Grupo Amaggi, uma empresa brasileira, queria se antecipar à questão”, diz Nepstad. A perspectiva de perder um mercado importante na Europa levantou questões sobre o melhor caminho a seguir. Em 2002, eles criaram o primeiro sistema para rastrear as práticas florestais dos agricultores que lhes vendiam soja. Em 2004, eles fizeram um convite a Nepstad para pesquisar as florestas em sua recém-adquirida propriedade Tanguro, um conjunto de fazendas de gado desmatadas que estavam em processo de conversão para campos de soja.

A esperança era que a pesquisa demonstrasse ao mundo o que realmente estava acontecendo nessas enormes fazendas de soja na Amazônia, fornecendo dados que poderiam contribuir para conversas sobre soja sustentável.

“Há vinte anos, havia muitas discussões sobre preservação ambiental e agricultura”, diz a Diretora de ESG, Comunicações e Conformidade do Grupo Amaggi, Juliana de Lavor Lopes. “Esses dois podem criar uma simbiose? Acho que sabíamos que [eles] poderiam trabalhar juntos, mas será que poderíamos provar isso?”

Para Nepstad, o convite também foi a oportunidade perfeita para realizar um experimento de fogo controlado em um local ideal. Após muitos debates, o IPAM decidiu aceitar.

“Muitas pessoas temiam que isso arruinasse nossa reputação, minasse nossa credibilidade junto às organizações de base – muitas ONGs achavam que estávamos nos vendendo”, diz Nepstad. “Algumas pessoas nos acusaram de termos sido comprados pelo Grupo Amaggi.”

Mas Nepstad foi muito claro quanto aos termos da parceria. Eles não aceitariam nenhum dinheiro da empresa além do que o Grupo Amaggi investiu nos prédios do campus da estação de pesquisa. E eles só apoiariam as atividades da fazenda na medida em que a ciência permitisse. A pesquisa relataria com precisão os impactos da agricultura sobre a floresta, sem restrições de publicação

Assim, em 2004, com poucos recursos financeiros, mas acompanhados por uma equipe dedicada de técnicos de campo e pesquisadores dos experimentos de seca no Pará, – alguns dos quais ainda trabalham na estação de campo atualmente – Woodwell e IPAM montaram um acampamento na Tanguro.

A vida na estação

As botas sujas de lama começam a fazer fila do lado de fora da porta do refeitório às 11h50. Donna Lucia serve o almoço pontualmente ao meio-dia.

Maria Lúcia Pinheiro Nascimento administra a cozinha da Tanguro há mais de 16 anos, preparando refeições fartas para cientistas e técnicos de campo famintos três vezes ao dia. O almoço e o jantar geralmente envolvem alguma carne grelhada ou cozida lentamente, arroz, feijão e uma salada fresca ou legumes assados. Hoje tem abóbora, abobrinha e sobras de linguiça e peito do churrasco de ontem à noite. O café da manhã é mais leve – pão de queijo, ovos, pão fresco, frutas e café – preparado e devorado antes do início do trabalho às 7h.

Muitos dos técnicos que vivem e trabalham aqui cinco dias por semana dizem que a Tanguro é como uma segunda casa, e seus colegas, uma segunda família. Para Dona Lúcia, como é chamada pelos funcionários e visitantes, cozinhar para a estação de pesquisa não é como cozinhar para a família. É realmente cozinhar para a família. Seu marido, Sebastião Nascimento, o “Seu Bate”, foi um dos primeiros técnicos de campo a trabalhar no experimento de seca no Pará. Ele voou para se juntar à equipe da Tanguro um ano após a fundação da empresa e trouxe sua família um ano depois, incluindo seu filho, Ebis Pinheiro de Nascimento, que também entrou como técnico de campo. Um terceiro técnico do Pará, Raimundo Mota Quintino, conhecido como “Santarém”, juntou-se à família quando se casou com a filha de Dona Lúcia.

“Estou com minha família”, diz ela. “Isso me traz alegria.”

Com ou sem parentesco, a equipe da Tanguro trabalha em conjunto, como uma família. A cooperação e o respeito são essenciais em um lugar tão remoto e desconectado (o wifi só se estende a cerca de 18 metros do prédio da cantina) como a Tanguro.

“Brincamos que é como se fosse o ‘Big Brother’”, diz o gerente de campo Darlisson Nunes da Costa. “Mas estamos realmente unidos e nos respeitamos mutuamente. É um ambiente maravilhoso para se trabalhar”.

Também pode ser um ambiente fisicamente desafiador, com longos dias de calor e umidade, preocupações com a segurança em uma floresta cheia de cobras e onças, porcos selvagens territoriais e terrenos que podem facilmente causar uma torção no tornozelo. Ao mesmo tempo, garantindo que os cientistas obtenham os dados de que precisam.

Todo técnico de campo precisa ser adaptável e versátil, pois, além dos horários das refeições, não há rotina diária. Sua manhã pode envolver o corte de videiras para encontrar um caminho para um riacho escondido, selecionado a partir de imagens de satélite como um local de amostragem. A tarde pode ser dedicada à solução de problemas em uma das torres de monitoramento de carbono.

“Não podemos dizer que temos um trabalho monótono”, diz Seu Bate. “Fazemos de tudo um pouco.”

Mesmo assim, cada um dos técnicos desenvolveu suas especialidades ao longo das décadas. Santarém ainda usa as habilidades de aquaviário de seu trabalho anterior como guia de pesca na cidade portuária do Pará que lhe deu o apelido. Ele leva a canoa para os reservatórios com frequência, ajudando os pesquisadores a extraírem núcleos de sedimentos. Seu Bate pode construir o que você precisar – seja a base de alumínio para uma câmara flutuante de monitoramento de metano ou um colar personalizado para segurar tubos de núcleo de solo pesados enquanto você coleta amostras, basta dar a ele 20 minutos e algumas ferramentas elétricas. Nunes da Costa mantém as atividades de campo da equipe organizadas a cada semana e consegue, sem esforço, abrir um caminho claro na floresta. O Ebis gosta de coletar dados, especialmente quando isso envolve a coleta de amostras de água ou de peixes nos cursos d’água de Tanguro. Para o coordenador de projetos científicos da estação, Dr. Leonardo Maracahipes-Santos, escalar a torre de carbono de 35 metros é como caminhar.

As pessoas que visitam a Tanguro variam. Às vezes, as semanas passam com apenas os técnicos de campo na residência e, às vezes, as pequenas casas em estilo de cabine e a alegre cantina da estação estão repletas de hóspedes.

Esta primavera já foi bastante movimentada. Maracahipes-Santos cuida das atividades diárias e organiza a equipe rotativa de visitantes. Em poucas semanas, ele passou de acompanhar

uma equipe de jornalistas brasileiros pelos locais de estudo, a trabalhar com colaboradores do Instituto Max Planck na manutenção de rotina das torres de carbono e a coordenar conversas entre pesquisadores visitantes e representantes do Grupo Amaggi sobre a remoção de várias barragens na propriedade.

E mesmo durante as semanas mais calmas, ainda há muita ciência a ser feita – coleta de amostras para estudos em andamento, execução de análises de dados, verificação de equipamentos. É difícil conseguir um dia de folga na Tanguro, mas pelo menos nunca é entediante.

“É muito interessante, porque fazemos parte de um projeto grandioso, que é montar experimentos em campo junto com os cientistas”, diz Nunes da Costa. “Nós nos sentimos um pouco como cientistas porque todo esse negócio começa no chão. Podemos começar com um pedaço de madeira colocado no chão e chegar até um artigo científico. Tenho muito orgulho. Não apenas de mim, mas de toda a equipe.”

Por sua vez, Dona Lucia se orgulha de alimentar a ciência na Tanguro.

“Tenho muito orgulho de estar em uma empresa como esta, hoje”, diz Dona Lúcia. “Hoje em dia, para trabalhar em uma empresa como essa, é preciso ter um diploma, e eu não tenho. Não tenho diploma de gastronomia. Não tenho nenhum diploma. Mas aprendo todos os dias”.

Um laboratório natural

O trabalho de campo termina às 16h, deixando Macedo, Atwood, Nunez da Costa e eu suados e exaustos após passar uma tarde vagando por áreas úmidas acidentadas em busca de leitos de riachos. A Atwood estava colocando medidores de temperatura a cada 500 metros acima e abaixo dos reservatórios. Ela está interessada nos impactos que esses pequenos corpos d’água têm sobre a bacia hidrográfica e até onde esses impactos se estendem. No entanto, os riachos amazônicos muitas vezes passam por segmentos intransponíveis de pântano, de modo que encontrar os locais de amostragem exige uma caminhada vigorosa e um bom facão.

Após a caminhada, encontramos o grupo de jornalistas visitantes no reservatório de Darro. Um dos maiores reservatórios de Tanguro, o Darro fornece água para a estação de pesquisa para chuveiros e limpeza. Em dias especialmente quentes, também é um ótimo local para nadar.

A água é quente – mais quente do que os riachos próximos, os dados de temperatura de Atwood confirmaram – mas ainda assim mais fria do que o ar abafado. Também é transparente. Nossos pés podem ser vistos pisando na faixa de água mais fria lá embaixo. Reflexos brancos e ondulantes se formam na superfície, um espelho perfeito das nuvens acima.

Na Amazônia, a água é tudo. É isso que torna possível a existência de florestas exuberantes. É o que liga uma fazenda de soja no Mato Grosso a estuários na foz do rio Amazonas. E é isso que conecta essa região ao clima global. As nuvens que se aglomeram acima de Darro ficam mais pesadas e mais escuras com a chuva enquanto nadamos. Embora parte dessa chuva caia de volta à Terra aqui, outra parte é empurrada para fora dos trópicos para cair em outros lugares.

“A água faz duas coisas”, diz o diretor do programa Woodwell Tropics, Dr. Mike Coe. “Primeiro: a chuva está caindo em outro lugar. Segundo: água é energia. É preciso uma enorme quantidade de energia para evaporar a água e essa energia é liberada em outro lugar quando chove. Assim, a energia do sol que cai aqui é transportada para todo o mundo. Isso é muito importante. Isso define o clima”.

Isso significa que, por meio da água, as mudanças aqui têm o potencial de causar grandes mudanças em todo o mundo. A localização da Tanguro em uma região da Amazônia que sofreu intenso desmatamento para a agricultura há apenas algumas décadas torna-a um local ideal para estudar essa causa e efeito.

“Quando você remove as florestas da paisagem, você muda algumas coisas fundamentalmente que não podem ser desfeitas”, diz Macedo. “Você altera a quantidade de água nos córregos, altera a profundidade de enraizamento das plantas na paisagem, altera todo o ciclo hidrológico.”

A Tanguro é bastante representativa das mudanças ocorridas em toda a região. É um mosaico de florestas naturais, campos de soja e algodão e alguns bosques de eucaliptos plantados. Algumas de suas bacias hidrográficas estão completamente dentro dos limites da floresta, outras passam completamente por terras agrícolas. Alguns riachos têm florestas bem preservadas ao longo de suas margens, enquanto outros estão em processo de restauração. As espécies amazônicas se misturam com as da savana brasileira. Está se tornando mais quente e mais seco à medida que o clima muda. Para os cientistas climáticos e ecologistas da Woodwell e do IPAM, esse é o laboratório natural perfeito.

Como o primeiro projeto de pesquisa lançado naquele laboratório, o experimento com fogo ganhou muita atenção.

“O Grupo Amaggi mobilizou a sociedade, havia jornalistas, repórteres de jornais e bombeiros. Pessoas da empresa e pessoas das cidades locais”, lembra Nepstad. Era um território novo, queimando intencionalmente a floresta para saber como isso mudava a paisagem. “Foi muito emocionante.”

A cada novo ano de queima, as percepções se revelavam. Em um ano particularmente quente e seco, a floresta queimou ainda mais do que o previsto. Nepstad se lembra de ter visto as chamas, na altura das canelas, ainda queimando às 2h da manhã seguinte. A mortalidade das árvores depois disso saltou de 6% para 50%.

“Isso foi trágico para aquele trecho de floresta”, diz Macedo. “Mas produziu percepções realmente importantes. Quase presciente. Basta olhar para 2023: foi um ano incrivelmente seco na Amazônia e, de repente, vimos florestas no meio da floresta tropical – áreas que costumavam ser muito úmidas para queimar agora podem queimar durante uma grande seca.”

Com o experimento de fogo em andamento, ainda havia quase 200.000 acres de terra disponíveis para estudo, então Nepstad convidou pesquisadores como Macedo, Coe e o Dr. Paulo Brando, que trabalhou com Nepstad no Pará, para explorar que outras histórias a Tanguro poderia contar sobre a Amazônia. Em seus 20 anos de história, mais de 180 artigos foram publicados a partir de pesquisas na estação, variando em tópicos desde mudanças hidrológicas até os limites climáticos da agricultura produtiva, a degradação do carbono florestal e o valor dos excrementos de anta para restauração. Brando atribui os resultados prolíficos da estação ao conhecimento de sua equipe.

“Parte da magia da Tanguro é aprender com as pessoas que trabalham há 20 anos na floresta. Eles têm um senso intuitivo do que está acontecendo com a saúde dessas florestas”, diz Brando.

Outro aspecto exclusivo da localização da Tanguro é sua posição em relação ao ecossistema maior. As centenas de pequenos riachos que cruzam a Tanguro formam as cabeceiras do rio Xingu, um importante afluente do tronco principal do Amazonas. Tanguro fica a apenas 60 quilômetros da Terra Indígena Xingu, por onde corre o rio de mesmo nome. Quaisquer distúrbios a montante de nutrientes, sedimentos ou fluxo de saída do córrego têm o potencial de se propagar até a reserva, afetando os meios de subsistência das comunidades indígenas.

“Os cursos d’água que estamos explorando na Tanguro fluem para a Reserva do Xingu. Portanto, é importante entender essas questões científicas de como a qualidade da água está sendo afetada pela agricultura como uma questão transfronteiriça”, diz Macedo. “A água conecta tudo.”

Conexão com a comunidade

Quando a Coordenadora Geral da Tanguro, Dra. Ludmila Rattis, iniciou sua pesquisa de pós-doutorado na estação de campo, Canarana era uma cidade diferente – pequena e dominada por homens o suficiente para que uma cientista ambiental não tivesse esperança de permanecer anônima. Rattis via seu nome escrito na comnda do bar como “menina do IPAM”. Ao andar na rua, sentia os olhares e às vezes era abordada por pessoas perguntando se ela trabalhava com os indígenas.

Era um lugar difícil de se estar, lembra ela. “Eu me sentia observada o tempo todo. Eu não podia fazer nada sem trazer comigo o nome de uma instituição. E a conexão com a Internet era de menos de um megabyte, não dava para assistir filmes em streaming”, diz Rattis. “Abrir um e-mail era um desafio.”

Trabalhar para uma organização ambiental sem fins lucrativos em uma cidade agrícola que deve sua própria existência ao desmatamento é, às vezes, difícil de navegar. Mas a agricultura está entrelaçada no DNA da Estação de Campo de Tanguro. Os cientistas do clima podem se arrepiar ao ver escavadeiras pressionando a vegetação rasteira, mas em última análise, a proximidade com a agricultura aqui levou a algumas das percepções mais valiosas da estação.

“Por estarmos neste lugar há muito tempo, podemos observar as mudanças à medida que elas ocorrem e dizer algo com muito mais confiança sobre os impactos mais amplos na Amazônia”, diz Macedo.

A parceria com o Grupo Amaggi também ajudou a conectar a ciência a grandes decisões no setor de soja. Em 2012, quando os debates sobre o futuro do Código Florestal brasileiro estavam em pleno andamento, Nepstad foi convidado a participar de uma viagem de campo a Tanguro com os principais legisladores que estavam elaborando o novo código, incluindo o senador Blairo Maggi, proprietário do Grupo Amaggi. Ver em primeira mão os experimentos de restauração florestal na estação ajudou a demonstrar a viabilidade da implementação das novas proteções. O Código Florestal foi revisado e a maioria de suas restrições ao desmatamento ainda está em vigor.

“Foi realmente a ciência que abriu essas portas”, diz Nepstad.

A pesquisa de Rattis, em particular, contribuiu para fortalecer as parcerias com fazendas da região. Ela passou o ano em Canarana conversando com os agricultores sobre a experiência deles com as mudanças climáticas – estações chuvosas que começam mais tarde, queda na produtividade das colheitas – e perguntando quais informações os modelos climáticos poderiam ser úteis. Aos poucos, à medida que Rattis apresentava a eles seus resultados, mostrando-lhes as previsões de chuva e temperatura e mantendo um diálogo aberto, ela construiu um relacionamento que não só fortaleceu sua relação com a comunidade, mas ajudou a orientar pesquisas futuras.

“Os fazendeiros lhe dirão se algo parece certo ou não, e 90% das vezes eles dirão ‘uau, você pode me enviar esse gráfico? Quero mostrar aos meus vizinhos’”, diz Rattis. Um novo estudo começou depois que conversas com um gerente de fazenda sugeriram uma conexão entre as florestas e a produção agrícola. “Eu disse que estávamos nos perguntando se as plantações produziriam mais perto da floresta, e ele disse: ‘isso faz sentido porque as plantas de algodão são maiores perto da borda da mata’.”

Os pesquisadores da Tanguro também estabeleceram conexões com os moradores da reserva indígena do Xingu, nas proximidades, formando parcerias com as aldeias para estudar os impactos a jusante dos incêndios recorrentes. Um professor da Universidade Federal da Amazônia (UFRA), Dr. Divino Silvério, que realizou sua pesquisa de doutorado no Tanguro, liderou grande parte desse trabalho.

“A ideia principal era integrar o conhecimento científico que tínhamos na Tanguro com o conhecimento tradicional dos povos indígenas, para quantificar melhor os impactos do fogo sobre as espécies que são usadas por eles para alimentação, construção e medicina”, diz Silvério.

Durante o estudo, Silvério e sua equipe de pesquisa visitaram a reserva do Xingu para discutir a pesquisa e compartilhar percepções. Eles também forneceram bolsas de estudo a vários estudantes indígenas para ajudar na coleta de dados e visitar a Tanguro para uma troca de conhecimentos.

“Os povos indígenas vêm manejando bem as florestas há séculos”, diz Silvério. “Mas agora temos a mudança climática. Está se tornando realmente urgente ter esse tipo de conversa no sentido de encontrar algumas soluções para mitigar os impactos das mudanças climáticas sobre os meios de subsistência dessas pessoas.”

Rattis também acredita que a Tanguro tem um papel a desempenhar como um centro educacional. No último ano, ela tem trabalhado para criar um prêmio de redação para estudantes locais, homenageando um funcionário do IPAM que defendeu a educação ambiental nos anos 2000.

“A Tanguro que temos hoje é o legado de muitas pessoas que trabalharam lá”, diz Rattis.

Como será o futuro?

Maracahipes-Santos já escalou essa torre milhares de vezes. Hoje ele sobe mais uma vez para prender uma corda sobressalente em um de seus suportes superiores. Se um de nós desmaiar

no meio da escalada, pelo menos eles poderão nos descer com cuidado. Se tudo der certo, escalaremos os 35 metros para cima e para trás com nossa própria força, ancorados no centro da torre com um mecanismo que trava como um cinto de segurança sob força repentina para baixo.

A torre em si é essencialmente uma escada coberta de vegetação, com vários medidores de gás e de temperatura presos a postes finos no topo. Três deles estão localizados ao redor da Tanguro para monitorar o movimento de dióxido de carbono, vapor de água e outros gases que entram e saem da paisagem. Essa torre em particular fica a 15 minutos de caminhada em uma seção de floresta intacta que foi usada como local de controle durante o experimento de incêndio.

Depois de verificar e verificar novamente minhas cordas, um grito de Maracahipes-Santos, que já estava no topo, sinalizou que era hora de começar a escalada.

Uma mão sobe um degrau, depois a outra. Os pés acompanham. Passo, passo, respire. Você deve se inclinar para trás, deixar que o arnês o segure e empurrar seu peso para cima com as pernas, mas um instinto inabalável me faz puxar com força a escada, de modo que, quando chego ao topo, meus antebraços estão tremendo. Suada, ofegante, corada, mas finalmente sobre o galpão. Maracahipes-Santos sorri e prende meu gancho de segurança em um dos suportes. Aqui em cima, somos mais altos do que as árvores.

Do alto da torre, você pode ler a história e o futuro desse lugar apenas virando a cabeça. A floresta se estende até o horizonte em uma direção, um mosaico ininterrupto de verde profundo. Em outro, é possível ver retângulos enormes de terra vermelha e tapetes uniformes de soja verde-clara cortados na paisagem. Em algum lugar escondido atrás de um bosque de eucaliptos plantados estão os telhados de metal corrugado da estação de pesquisa. A chuva está caindo no horizonte.

Há poucas décadas, tudo isso era floresta. Apenas outro aglomerado impossivelmente espesso de organismos vivos que respiram, morrem e crescem novamente em um dos ecossistemas de maior biodiversidade do planeta. Agora, os instrumentos de sensoriamento remoto documentam seu declínio.

A pesquisa na Tanguro é orientada por uma grande questão: “Qual é o futuro da Amazônia?” Mas a resposta a essa pergunta dependerá: dos cientistas que continuarem a vir a Tanguro para entender como esse ecossistema está mudando; dos técnicos de campo que tornarem possível conduzir a ciência na floresta com segurança; dos fazendeiros que se orgulharem de cuidar das florestas que estão em suas terras; dos funcionários do governo que criarem políticas que reflitam a ciência; e das decisões de pessoas a milhares de quilômetros de distância para reverter a mudança climática.

“Quando se faz uma pesquisa sobre essa floresta, percebe-se que é um sistema incrivelmente resistente, que agora está enfrentando estresses e distúrbios cada vez mais fortes. Portanto, ele precisa de ajuda e precisa ter uma chance, mas continuará”, diz Nepstad. “E acho que a Tanguro tem um papel importante nisso.”

Os últimos 20 anos na Tanguro contribuíram para direcionar a Amazônia para um futuro mais promissor. O que os próximos 20 anos nos trarão?

“Minha esperança”, diz Rattis, “é que em 20 anos não estaremos mais lidando com o desmatamento. ‘Lembra-se daquela vez em que tivemos que convencer as pessoas a não derrubar a floresta? Estou muito feliz por termos superado isso’”.

The sky opens up just as our truck leaves the last stretch of paved road. Water Program Director Dr. Marcia Macedo squints to stay focused on what she can see between wipes of the windshield. Within minutes, our path is transformed from a dirt road into a riverbed of bright orange mud, rutted from the passing of heavy trucks carrying soy off surrounding farms. Macedo swerves to dodge bumps and dips, but pretty soon there are more of them than there is flat road. We brace for the puddles, peering out windows spattered with orange spray.

It’s a Monday morning in the rainy season at the edge of the Amazon, and we’re commuting to work.

Tanguro Field Station lies about an hour’s drive from Canarana, the nearest town, located in a region of Brazil sometimes referred to as the arc of deforestation. Several decades ago, agriculture began surging into the southern reaches of the Amazon rainforest here, carving out rectangular patches of farmland from primary forest. For most of our drive, we are flanked only by mega-fields of soybean or scrubby cattle pastures.

Macedo, who has been conducting research at Tanguro since 2007, remembers a time when the drive could be marked by crossing a threshold from the Cerrado—Brazil’s woody savanna biome—into the Amazon. Now, clearing near the road has obscured that natural transition. Eventually clumps of lush green loom closer out of the rain and we know we’re nearly there.

Since its founding in 2004, Tanguro has offered researchers from around the world the opportunity to investigate big questions about how climate change and deforestation are affecting the Amazon. Macedo and her team have come to study Tanguro’s streams and reservoirs. 

We pull to a stop outside the research station, hauling suitcases wrapped in plastic trash bags out of the truck bed. Research assistant Zoë Dietrich, clutches several vital electronic components to her chest, ferrying them to a screened-in porch to keep them out of the rain. Postdoctoral researcher Dr. Abra Atwood starts digging out sediment core tubes from a pile of equipment. The clouds drift off and the work day at Tanguro begins.

I. The Founding

It was a controversial decision at the time. “The decision to set up on the Tanguro ranch almost drove a wedge through us,” recalls Tanguro founder, Dr. Daniel Nepstad. “We had a discussion that lasted two days.”

Fourteen years prior, Nepstad had established the Amazon program at Woodwell Climate (then the Woods Hole Research Center) in the state of Pará, studying the resilience of Amazon forests during long dry seasons. This work gave rise to a new research institute based in Brazil. In 1995, Nepstad co-founded the Amazon Environmental Research Institute (IPAM) in Belém to pursue policy-relevant science that could inform sustainable development in the Amazon. Woodwell Climate and IPAM began conducting simulated drought experiments and found that the rainforest, long thought to be immune to fire, lost that resistance during severe droughts. To investigate the implications of this, Nepstad realized, they needed a new experiment somewhere at the edge of the Amazon, where it’s drier year-round.

Nepstad had been spending more and more time in the state of Mato Grosso, fascinated by the expansion of soybean cultivation into the Amazon there. During his search for a new study site, Grupo Amaggi reached out with a remarkable invitation.

Grupo Amaggi was, at the time, the largest soy producer in the world, and soy was rapidly becoming environmental enemy number one, as hundreds of thousands of acres of forests fell to expand its cultivation.

“But Grupo Amaggi, a Brazilian company, wanted to get out in front of the issue,” says Nepstad. The prospect of losing a major market in Europe raised questions about the best way forward. In 2002 they set up the first system for tracing the forest practices of the farmers who sold them soy. And in 2004 they extended an invitation to Nepstad to study the forests on their newly acquired Tanguro property— an amalgamation of previously-cleared cattle ranches they were in the process of converting to soy fields. 

The hope was that the research would demonstrate to the world what was really happening in these massive soy farms in the Amazon, providing data that could contribute to conversations around sustainable soy.

“Twenty years ago there were lots of discussions about environmental preservation and agriculture,” says Grupo Amaggi’s ESG, Communications and Compliance Director, Juliana de Lavor Lopes. “Could those two create a symbiosis? I think we knew [they] could work together, but could we prove that?”

 For Nepstad, the invitation was also the perfect opportunity to run a controlled fire experiment in an ideal location. After much debate, IPAM decided to accept. 

“There were a lot of folks worried that this would ruin our reputation, undermine our credibility with grassroots organizations— a lot of NGOs felt like we were selling out,” says Nepstad. “Some people accused us of being bought off by Grupo Amaggi.”

But Nepstad was very clear on the terms of the partnership. They would accept no money from the company other than what Grupo Amaggi invested in the buildings on the research station campus. And they would only support the farm’s activities as far as the science allowed. The research would accurately report the impacts of agriculture on the forest, with no restrictions on publication. 

So in 2004, barely funded, but accompanied by a dedicated team of field technicians and researchers from the drought experiments in Pará— some of whom are still employed at the field station today— Woodwell and IPAM set up camp at Tanguro.

II. Life at the Station

Muddy boots start lining up outside the door to the cafeteria at 11:50am. Dona Lúcia sets lunch out promptly at noon. 

Maria Lúcia Pinheiro Nascimento has run the kitchen at Tanguro for over 16 years, cooking filling meals for hungry scientists and field technicians three times a day. Lunch and dinner usually involve some slow-cooked or grilled meat, rice, beans, and a fresh salad or roasted vegetables. Today there’s abóbora, a green-skinned pumpkin, and leftover sausage and brisket from last night’s churrasco. Breakfast is a lighter affair— pão de queijo, eggs, fresh bread, fruit, and coffee— set out and scarfed down before work starts at 7 am.

Many of the technicians who live and work here five days a week say Tanguro is like a second home, their peers a second family. For Dona Lúcia, as she’s called by staff and visitors alike, cooking for the research station isn’t just like cooking for family. It is cooking for family. Her husband, Sebastião Nascimento, “Seu Bate”, was one of the original field technicians working on the drought experiment in Pará. He flew down to join the crew at Tanguro a year after it was founded and brought his family down a year later, including his son, Ebis Pinheiro de Nascimento, who also joined as a field technician. A third technician from Pará, Raimundo Mota Quintino, known as “Santarém”, joined the family when he married Dona Lúcia’s daughter. 

“I’m with my family,” she says. “It gives me joy.”

Related or not, the team at Tanguro works together like a family. Cooperation and respect are essential in a place as remote and disconnected (wifi only extends 60ft from the cafeteria building) as Tanguro. 

“We joke that it’s like “Big Brother”,” says Field Manager, Darlisson Nunes da Costa. “But we are really united and we respect each other. That’s a wonderful environment to work in.” 

It can also be a physically challenging environment, with long days in the heat and humidity, navigating safety concerns in a forest full of snakes and jaguars, territorial wild pigs and terrain that could easily twist an ankle. All the while ensuring the scientists get the data they need.

Every field technician has to be adaptable and multi-talented, because aside from meal times there is no day-to-day routine. Your morning might involve slashing vines to find a path to a hidden stream, selected from satellite imagery as a sampling location. The afternoon could be spent troubleshooting errors at one of the carbon-monitoring towers. 

“We can’t say we have a fixed job,” says Seu Bate. “We do a bit of everything.”

All the same, the technicians have each developed their specialties over the decades. Santarém still uses waterman skills from his previous job as a fishing guide in the port city in Pará that gave him his nickname. He takes the canoe out on the reservoirs often, helping researchers pull sediment cores. Seu Bate can build whatever you need— whether it’s the aluminum base for a floating methane-monitoring chamber, or a custom collar to hold unwieldy soil core tubes while you sample them, just give him 20 minutes and some power tools. Nunes da Costa keeps the team’s field activities organized each week and can effortlessly cut a clear path through the forest. Ebis enjoys data collection, especially when it involves sampling the water or fishes in Tanguro’s waterways. For the station’s Scientific Projects Coordinator, Dr. Leonardo Maracahipes-Santos, climbing the 118 ft carbon tower is just like walking.

Outsider visits to Tanguro fluctuate. Sometimes weeks pass with only the field techs in residence, and sometimes the station’s small cabin-style houses and cheerful cafeteria are crawling with guests.

This spring has already been a busy one. Maracahipes-Santos handles day-to-day operations and organizes the rotating cast of visitors. In a few short weeks, he went from touring  a crew of Brazilian journalists around the study sites, to working with collaborators from the Max Planck institute on routine maintenance to the carbon towers, to coordinating conversations between visiting researchers and Grupo Amaggi representatives about removing several dams on the property. 

And even during slow weeks, there is plenty of science left to do—collecting samples for ongoing studies, running data analyses, checking on equipment. A day off is hard to come by at Tanguro, but at least it’s never boring.

“It’s very interesting, because we are part of a grand thing, which is to set up experiments in the field together with scientists,” says Nunes da Costa. “And we feel a little bit like scientists, because this whole business all starts on the ground. We can start from a piece of wood placed on the ground, and get all the way up to a scientific article. I feel very proud. Not only of me, but of the whole team.”

For her part, Dona Lúcia takes great pride in feeding the science at Tanguro. 

“I’m very proud to be in a company like this, today,” says Dona Lúcia. “Nowadays, to work in a company like this, you need a degree, and I don’t have one. I don’t have a culinary degree. I don’t have any degree. But I learn every day.”

III. A Natural Laboratory

Field work wraps up at 4pm, leaving Macedo, Atwood, Nunes da Costa, and me sweaty and exhausted from an afternoon spent trudging through uneven wetlands to find stream channels. Atwood was dropping temperature loggers every 500 meters above and below reservoirs. She’s interested in the impacts these small water bodies have on the watershed, and how far downstream those impacts extend. But Amazonian streams often twist through impassable segments of marsh, so finding the sample sites requires vigorous hiking and a good machete. 

After our hike, we rendezvous with the group of visiting journalists at the Darro Reservoir. One of the largest reservoirs at Tanguro, the Darro provides water to the research station for showers and cleaning. On especially hot days, it also makes a great swimming hole. 

The water is warm—warmer than nearby streams, Atwood’s temperature data has confirmed—but still cooler than the muggy air. It’s also glassy clear. Our feet are visible treading the band of colder water down below. Billowing white reflections form on the surface, a perfect mirror of the clouds above.

Water is everything in the Amazon. It’s what makes the lush forests possible. It’s what connects a soy farm in Mato Grosso to estuaries at the yawing mouth of the Amazon River. And it’s what connects this region to the global climate. The clouds clustering above Darro grow heavier and darker with rain while we swim. Although much of that rain will fall back to Earth here, a large portion of it gets pushed out from the tropics to fall in other places.

“Water does two things,” says Woodwell Tropics Program Director, Dr. Mike Coe. “One: it’s rainfall somewhere else. Two: water is energy. It takes a huge amount of energy to evaporate water and that energy gets released somewhere else when it rains. So the energy from the sun that falls here gets transported around the world. That’s huge. That drives climate.”

Which means that, through water, changes here have the potential to cause major changes across the globe. Tanguro’s location in a region of the Amazon that underwent intense deforestation for agriculture just a few decades ago makes it an ideal place to study that cause and effect.

“Once you remove forests from the landscape, you change some things fundamentally that you can’t really undo,” says Macedo. “You change the amount of water in streams, you change the rooting depth of the plants on the landscape, you change the entire hydrological cycle.” 

Tanguro is pretty representative of the changes experienced across the region. It’s a patchwork of natural forest, soy and cotton fields, and some planted eucalyptus groves. Some of its watersheds lie completely within the bounds of the forest, others run completely through agricultural land. Some streams have well preserved forests along their banks, while others are in the process of restoration. Amazonian species mix with those from the Brazilian savanna. It’s becoming hotter and drier as the climate changes. For the climate scientists and ecologists at Woodwell and IPAM, it’s the perfect natural laboratory. 

As the first research project launched in that laboratory, the fire experiment garnered much fanfare.

“Grupo Amaggi had mobilized society, there were journalists and newspaper reporters and firefighters. People from the company and people from the local towns,” recalls Nepstad. It was new territory, intentionally burning the forest to learn how it changed the landscape. “It was really exciting.”

With each new year of burning, insights revealed themselves. One particularly hot, dry year, the forest burned even more than predicted. Nepstad recalled seeing flames, shin-high, still burning at 2 am the next morning. Tree mortality afterward jumped from its usual 6% up to 50%.

“That was tragic for that patch of forest,” says Macedo. “But it has yielded really important insights. Almost prescient. Just look at 2023: it was an incredibly dry year in the Amazon, and all of a sudden we saw fires in the very middle of the rainforest—areas that used to be much too wet to burn can now burn during a big drought.” 

With the fire experiment underway, there was still nearly 200,000 acres of land available to study, so Nepstad invited researchers like Macedo, Coe, and Dr. Paulo Brando, who worked with Nepstad in Pará, to explore what other stories Tanguro might be able to tell about the Amazon. In its 20 year history, over 180 papers have been published from research at the station, ranging in topic from hydrologic changes, to the climatic limits on productive agriculture, to the degradation of forest carbon, to the value of tapir poop for restoration. Brando attributes the station’s prolific results to the knowledge of its staff.

“Part of Tanguro’s magic is to learn from the people who have been working for 20 years in the forest. They have an intuitive sense of what is happening with these forests’ health,” says Brando.

Another unique aspect of Tanguro’s location is where it sits in relation to the larger ecosystem. The hundreds of small streams that criss-cross Tanguro form the headwaters of the Xingu River—a major tributary to the main stem of the Amazon. Tanguro is just 60 kilometers from the Xingu Indigenous Territory, through which the river of the same name runs. Any upstream disturbances to nutrients, sediments, or stream outflow have the potential to ripple down to the reserve, impacting the livelihoods of Indigenous communities within. 

“The headwater streams that we’re studying here at Tanguro drain into the Xingu reserve. So, these scientific questions of how water quality is being impacted by agriculture are important to understand as a cross-boundary issue,” says Macedo. “Water connects everything.”

IV. Connecting to the Community

When Tanguro General Coordinator, Dr. Ludmila Rattis, started her postdoctoral research at the field station, Canarana was a different town—small and male-dominated enough that a female environmental scientist had no hope of staying anonymous. Rattis would see her name written on bar tabs as “IPAM’s girl.” She went for runs and felt the stares.

It was a hard place to be, she recalls. “I felt watched all the time. I couldn’t do anything without bringing with me the name of an institution. And the internet connection was less than one megabyte, so Netflix was a challenge,” Rattis says. “Opening an email was a challenge.”

Working for an environmental non-profit in a farm town that owes its very existence to deforestation is sometimes tricky to navigate. But agriculture is woven into the DNA of Tanguro Field Station. Climate scientists may flinch to see bulldozers pressing into the undergrowth, but ultimately the proximity to agriculture here is what has yielded some of the station’s most valuable insights. 

“By being here in this place for a long time, we’re able to observe changes as they happen, and say something much more confidently about what the broader impacts are on the Amazon,” says Macedo.

The partnership with Grupo Amaggi has also helped connect science to big decisions in the soy sector. In 2012, when debates over the future of Brazil’s forest code were roaring away, Nepstad was invited to join a field trip to Tanguro with the main lawmakers shaping the new code—including Senator Blairo Maggi, an owner of Grupo Amaggi. Seeing firsthand the experiments with forest restoration at the station helped demonstrate the feasibility of implementing the new protections. The forest code was revised and most of its restrictions on forest clearing are still in place today.

“It was really the science that opened these doors,” says Nepstad. 

Rattis’s research, in particular, has gone a long way toward strengthening partnerships with farms around the region. She spent her year in Canarana talking with farmers about their experience of climate change—rainy seasons starting later, crop yields dropping—and asking what information they might find useful from climate models. Slowly, as she came back to them with her results, showing them rainfall and temperature predictions and keeping a dialogue open, she built a rapport that not only strengthened her relationship with the community, but helped guide future research. 

“The farmers will tell you whether something looks right or not, and 90% of the time they’d say ‘wow, can you please send me that graphic? I want to show my neighbors,’” says Rattis. One new study even began after conversations with a farm manager hinted at a connection between forests and crop production. “I said we were wondering if the crops would produce more closer to the forest, and he said, ‘that makes sense because the cotton plants are bigger closer to the forest edge.’”

Researchers at Tanguro have also built connections with residents of the nearby Xingu Indigenous reserve, partnering with villages to study the downstream impacts of recurring fires. A professor with the Federal University of the Amazon (UFRA), Dr. Divino Silvério, who conducted his doctoral research at Tanguro, has led much of this work. 

“The main idea was to integrate the scientific knowledge we had at Tanguro, with the traditional knowledge of the Indigenous people, to better quantify the impacts of fire on species that are used by them for food, construction, and medicine,” says Silvério. 

 During the study, Silvério and his research team visited the Xingu reserve to discuss the research and share insights. They also provided scholarships to several Indigenous students to help in the data collection and visit Tanguro for a knowledge exchange. 

“Indigenous people have been managing the forests well for centuries,” says Silvério. “But now we have climate change. It’s becoming really urgent to have these kinds of conversations, to come up with some solutions to mitigate the impacts of climate change on the livelihoods of these people.”

Rattis also believes Tanguro has a role to play as an education hub. Over the last year she has been working to create an essay prize for local students, honoring an IPAM employee who championed environmental education in the 2000s.

“The Tanguro we have today is the legacy of the many people that have worked there,” says Rattis.

V. What does the future look like?

Maracahipes-Santos has climbed this tower a thousand times. Today he’s climbing it once more, to anchor a back-up belay line to one of its top struts. If one of us passes out mid-climb, at least they’ll be able to lower us down gently. If all goes well, we will be climbing the 118 feet up and back under our own power, anchored to the center of the tower with a mechanism that locks like a seatbelt under sudden downward force.

The tower itself is essentially an overgrown ladder, with various gas and weather analyzers strapped to spindly poles at the top. There are three of them stationed around Tanguro to monitor the movement of carbon dioxide, water vapor, and other gasses into and out of the landscape. This particular tower is a 15 minute hike into a section of intact forest that was used as the control site during the fire experiment. 

After checking and rechecking my tethers, a shout from Maracahipes-Santos, already at the top, signaled it was time to start the climb.

One hand up a rung, then the other. Feet to follow. Step, step, breathe. You’re supposed to lean back, let the harness hold you and push your weight up with your legs, but an unshakable instinct makes me pull tight to the ladder, so when I reach the top my forearms are shaking. Sweaty, breathless, flushed, but above the canopy at last. Maracahipes-Santos smiles and attaches my safety hook to one of the struts. Up here, we are taller than the trees.

From the top of the tower, you can read the history and future of this place, just by turning your head. Forest stretches to the horizon in one direction, an unbroken mosaic of deep green. In another, you can see massive rectangles of red dirt and uniform carpets of pale green soy cut into the landscape. Somewhere hidden behind a copse of planted eucalyptus are the corrugated metal roofs of the research station. Rain is falling on the horizon. 

Not too many decades ago, this was all forest. Just another impossibly thick cluster of living organisms breathing and dying and growing anew in one of the most densely biodiverse ecosystems on the planet. Now, the vigilant scientific instruments whizzing away up here document its decline. 

Research at Tanguro is driven by one big question: “What is the future of the Amazon?” But the answer to that question will depend — on scientists continuing to come to Tanguro to understand how this ecosystem is changing, on the field technicians making it possible to conduct science in the forest safely, on farmers taking pride in caring for the forests that stand on their land, on government officials building policies that reflect science, and on the decisions of people thousands of miles away to reverse climate change.   

“When you’re doing research on this forest, you realize it is an amazingly tough system that is now being faced with tougher and tougher stresses and disturbances. So it needs help, and it needs to be given a chance, but it will continue,” says Nepstad. “And I think Tanguro has a big role to play in that.”

The past 20 years at Tanguro have done much to point the Amazon towards a more hopeful future. What will the next 20 bring?

“My hope,” says Rattis, “is that in 20 years we won’t be dealing with deforestation anymore. ‘Remember that time when we had to convince people not to cut down the forest? I’m so glad we’re past that.’”

“Why not float the aquatic greenhouse gas chamber on a surfboard?” Tropics Program Director Dr. Mike Coe suggested in one of our team meetings, and I could feel the gears in my brain begin turning. I started a sketch… If mounted on a surfboard, we would need a method to open the chamber, flushing it with outside air. Back in my office, I asked Google “what turns electrical energy into mechanical energy?” Google was quick to respond, “Motor.” Right, thank you, Google. Next, I typed, “motor that pushes something up.” Google replied, “linear actuator.” Three clicks later and I had ordered my first linear actuator for 35 bucks. 

Three days later, that linear actuator sat expectantly on my desk. One red wire and one black wire, “12V DC” printed on its side. I turned back to Google, “How to wire a linear actuator?” Opening the first hit, I skimmed through the photos and diagrams. None of them striking my fancy, I moved on to the second hit: Step-by-step instructions, clear photos, even open-source code to program my Arduino microcontroller board – nice! Within an hour, my linear actuator was extending and retracting on command, ready to be mounted in an autonomous greenhouse gas chamber.

Adding the actuator to my sketch, I popped into Senior Research Scientist Kathleen Savage’s office to hear her thoughts. Savage always has new ideas brewing, and she suggested adding a feature that would allow the chamber to function on water and on land. The chambers are the product of a Fund for Climate Solutions (FCS) grant led by Savage to quantify carbon dioxide and methane emissions from small water bodies like lakes, ponds, and reservoirs. Because there are no low-cost and auto-sampling tools available on the market, we have been developing a new instrument to measure these emissions. 

DIY science

“Chamber” is a fancy word for the upside-down buckets we use to measure how fast greenhouse gasses are released from different surfaces. By resting a bucket upside-down on a patch of soil or grass or water and measuring how fast gas concentrations increase or decrease inside the bucket, we can calculate a “flux” of gas over a set area and time. Common methods of measuring fluxes require manually collecting gas samples from a chamber to be processed in a lab, or connecting the chamber to a high precision analyzer that can cost around $40,000. These methods are costly in salary time and equipment, limiting where, when, and how often people can sample—usually daytime and in accessible areas and times of the year. We need new low-cost and autonomous systems that can measure around the clock to improve carbon emissions estimates. The recent commercialization of cheaper sensors and control systems to operate them, like the Arduino microcontroller, now make these developments possible. 

I’m building a new floating chamber that measures aquatic fluxes autonomously using a $15 methane sensor and a $78 carbon dioxide sensor, improving previous designs published by Dr. David Bastviken’s group at Linköping University in Sweden. Powered by a solar panel and battery, the sensors measure gas concentrations, temperature, and humidity inside the chamber every 30 seconds. The data is stored on an SD card and transmitted within 50 meters via radio. The radio transmission allows us to check that the chamber is functioning properly from the shore and to see chamber measurements in real time. When gas concentrations have increased enough to discern a flux, the linear actuator extends to open the chamber, flushing the interior with outside air before retracting to close the chamber again for another flux measurement. Calibrating the chamber with a high precision analyzer in the field shows the low-cost sensors perform well, with an accuracy of approximately 1 ppm for methane and 3 ppm for carbon dioxide.

Field deployment

 I first tested chamber prototypes last July on agricultural reservoirs at the Tanguro Field Station in Brazil. At the end of our field campaign, I left one chamber deployed to see how long the electronics would last and which components might eventually fail. After helping me deploy and calibrate the chamber, field technician Raimundo “Santarém” Quintino monitored it, checking its “vital signs” via radio every few weeks. In January, he noticed the linear actuator had stopped pushing the chamber open. 

During a follow-up field campaign in March, I brought a couple of extra linear actuators and five more chambers to deploy on additional reservoirs at Tanguro. Tanguro staff and I worked together to modify chamber components that didn’t function well in the first deployment. These modifications included swapping the materials of the floating foam bases and improving the mounting mechanisms of the linear actuator and chamber hinge. Our adjustments were informed by recommendations from a Laboratory Operations Manager at the University of Maine in Orono (Christopher London), whom I met while doing fieldwork at the nearby Howland Research Forest. Woods Hole locals, such as John Driscoll and Fred Palmer of the Woodwell Climate Facilities department, kite foiler and carpenter Tad Ryan, and employees at Eastman’s Hardware, have also offered transformative recommendations on building materials and techniques to stabilize the floating chambers.

Working hands-on with the floating chambers on the reservoirs, Santarém, Dr. Leonardo Maracahipes-Santos, Tanguro’s Scientific Projects Coordinator, and Sebastião “Seu Bate” Nascimento of Tanguro Field Station have made invaluable improvements to the chamber design and deployments. A few of their contributions include advice on safe deployment locations, monitoring and collecting data from the chambers over time, and constructing aluminum and galvanized steel components for the floating bases. They also designed a new mount for the most recent chamber addition—a bubble trap that uses an inexpensive pressure sensor to autonomously measure the volume of gas released as bubbles. 

Freshwater ecosystems worldwide emit nearly half as much carbon dioxide and methane as fossil fuel combustion. On the Amazon-Cerrado frontier, where Tanguro is located, there are hundreds of thousands of small agricultural reservoirs, which are important, yet overlooked, greenhouse gas sources. These artificial ponds—installed to provide drinking water for cattle, facilitate road crossings, or supply energy at the farm scale—can persist for decades, creating low-oxygen conditions that drive methane production. Monthly sampling of six reservoirs over a year by Water Program Director Dr. Marcia Macedo revealed high methane and carbon dioxide emissions, varying with season and reservoir size. But these measurements did not capture the significant variability that can occur on daily, monthly, and annual time scales, including transient “hot spots” and “hot moments” of high greenhouse gas emissions. 

This lack of frequent measurements hinders climate scientists’ ability to integrate emissions at the reservoir scale in order to estimate cumulative greenhouse gas emissions at the landscape scale. The autonomous floating chambers will address that gap, enabling comprehensive carbon monitoring and modeling of the reservoirs.

From the tropics to the Arctic

Additionally, these chambers are versatile tools that can be used across different environments. Funded by a subsequent FCS grant, six new floating chambers will accompany me to the Yukon-Kuskokwim Delta, Alaska, this summer to measure greenhouse gas emissions from Arctic ponds. The chambers will supply the frequent data necessary to constrain the LAKE model utilized by Arctic Program scientists Dr. Elchin Jafarov and Andrew Mullen. The model predicts variations in carbon emissions from ponds, providing insight into processes regulating methane and carbon dioxide. By applying the LAKE model to both Arctic ponds and Amazon reservoirs, we can gain a deeper understanding of their impacts on regional greenhouse gas budgets. 

“Deploying floating chambers will streamline the process of gathering aquatic data and enhance the temporal resolution of the data, which is vital for modeling and currently absent in existing datasets,” notes Jafarov.  

Problem-solving and collaboration

While calibrating the low-cost sensors in our boat one March afternoon, Santarém and I noticed the linear actuator on another nearby chamber wasn’t retracting and extending as it should. Expecting another replacement was in store, we tuned into the radio and popped open the electronics case to check for “symptoms.” Blinking lights and radio silence revealed an entirely new and perplexing issue causing the malfunction. 

Building this system from the ground up over the last year, the one constant has been mind-bending electronics puzzles that keep me up at night. As a biogeochemist by training, these problems usually require some tinkering, a dictionary, a lot of Googling, and sometimes bugging electrical engineers down the street at the Woods Hole Oceanographic Institution (Lane Abrams) and Spark Climate Solutions (Bashir Ziady), whose advice and contributions have substantially improved the chambers’ electrical designs. Each problem can usually be traced to a perfectly logical, satisfying solution, leaving me feeling wiser and excited to tackle the next one. I’ve tracked this new problem down to something potentially involving a “memory-leaking variable declaration” in my new bubble trap programming code. I might’ve fixed it with a “watchdog timer.” Both are new words for me, too. If the watchdog timer doesn’t pan out, Santarém and I will try another fix. 

Designing, building, and testing these chambers has been an iterative and constantly evolving process. What works well? What doesn’t? How can we do this more simply? Using less energy? For a lower cost? How can we improve the design so that other researchers can easily build these floating chambers as well? Soon we plan to publish open-source instructions detailing how to build and troubleshoot the floating chambers—I have already sent preliminary instructions to three interested research groups. I’m lucky to collaborate with many talented people from Woods Hole to Maine and Brazil, many of whom are as new to chambers and fluxes as I am to engineering. Nevertheless, these floating chambers incorporate a brilliant flourish from each of them.

When it comes to reversing climate change, trees are a big deal. Globally, forests absorb nearly 16 billion metric tonnes of carbon dioxide per year, and currently hold 861 gigatonnes of carbon in their branches, leaves, roots, and soils. This makes them a valuable global carbon sink, and makes preserving and maintaining healthy forests a vital strategy in combating climate change.

But not every forest absorbs and stores carbon in the same way, and the threats facing each are complex. A nuanced understanding of how carbon moves through forest ecosystems helps us build better strategies to protect them. Here’s how the world’s different forests help keep the world cool, and how we can help keep them standing.

Tropical forest carbon

Tropical rainforests are models of forest productivity. Trees use carbon in the process of photosynthesis, integrating it into their trunks, branches, leaves, and roots. When part or all of a tree dies and falls to the ground, it is consumed by microorganisms and carbon is released in the process of decay. In the heat and humidity of the tropics, vegetation grows so rapidly that decaying organic matter is almost immediately re-incorporated into new growth. Nearly all the carbon stored in tropical forests exists within the plants growing aboveground. 

Studies estimate that tropical forests alone are responsible for holding back more than 1 degree C of atmospheric warming. 75% of that is due simply to the amount of carbon they store. The other 25% comes from the cooling effects of shading, pumping water into the atmosphere and creating clouds, and disrupting airflow.  

In many tropical forest regions, there is a tension between forests and agricultural expansion. In the Amazon rainforest, land grabbing for commodity uses like cattle ranching or soy farming has advanced deforestation. Increasing protected forest areas and strengthening the rights of Indigenous communities to manage their own territories has proven effective at reducing deforestation and its associated emissions in Brazil. “Undesignated lands” have the highest levels of land grabbing and deforestation.

Fire has also become a growing threat to the Amazon in recent years, used as a tool to clear land by people illegally deforesting. When rainforests have been fragmented and degraded, their edges become drier and more susceptible to out-of-control burning, which weakens the forest even further. Enforcing and strengthening existing anti-deforestation laws are crucial to reduce carbon losses.

In Africa’s Congo rainforest, clearing is usually for small subsistence farms which, in aggregate, have a large effect on forest loss and degradation. Mobilizing finance to scale up agricultural intensification efforts and rural enterprise within communities, while implementing protection measures, can help decrease the rate of forest destruction. Forests and other intact natural landscapes such as wetlands and peatlands could be the focus of climate finance mechanisms that encourage sustainable landscape management initiatives. 

Temperate forest carbon

Much of the forest carbon in the temperate zone is stored in the trees as well— particularly in areas where high rainfall supports the growth of dense forests that are resilient against disturbances like drought or disease. The temperate rainforests of the Northwestern United States, Chile, Australia, and New Zealand contain some of the largest and oldest trees in the world. 

Two thirds of the total carbon sink in temperate forests can be attributed to the annual increase in “live biomass”, or the yearly growth of living trees within the forest. This makes the protection of mature and old-growth temperate forests paramount, since older forests add more carbon per year than younger ones and have much larger carbon stocks. Timber harvesting represents one of the most significant risks to the carbon stocks in temperate forests, particularly in the United States where 76% of mature and old growth forests go unprotected from logging. Fire and insects are also significant threats to temperate forests particularly in areas of low rainfall or periodic drought.  

Maintaining the temperate forest sink means reducing the area of logging, by both removing the incentive to manage public forests for economic uses and by providing private forest owners with incentives to protect their land. Low-impact harvesting practices and better recycling of wood products can also help bring down carbon losses from temperate forests. In areas threatened by increasingly severe wildfires, reducing fuel loads especially near settlements can help protect lives and property. 

Boreal forest carbon

In boreal forests, the real wealth of carbon is below the ground. In colder climates, the processes of decay that result in emissions tend to lag behind the process of photosynthesis which locks away carbon in organic matter. Over millennia, that imbalance has slowly built up a massive carbon pool in boreal soils. Decay is even further slowed in areas of permafrost, where the ground stays frozen nearly year round. It estimated that 80 to 90% of all carbon in boreal forests is stored belowground. The aboveground forest helps to protect belowground carbon from warming, thaw, decay, and erosion.

Wildfire— although a natural element in boreal forests— represents one of the greatest threats to boreal forest carbon. With increased temperatures, rising more than twice as fast in boreal forests compared to lower latitudes, and more frequent and long-lasting droughts, boreal forests are now experiencing more frequent and intense wildfires. The hotter and more often a stand of boreal forest catches fire, the deeper into the soil carbon pool the fire will burn, sending centuries-old carbon up in smoke in an instant. Logging of high-carbon primary forests is also a big issue in the boreal.

The number one protection for boreal forest carbon is reducing fossil fuel emissions. Only reversing climate change will bring boreal fires back to the historical levels these forests evolved with. In the meantime, active fire management in boreal forests offers a cost effective strategy to reduce emissions— studies found it could cost less than 13 dollars per ton of carbon dioxide emissions avoided. Strategies for fire management included both putting out fires that threaten large emissions, and controlled and cultural burning outside of the fire season to reduce the flammability of the landscape.

Fund for Climate Solutions awards five new grants

From the Arctic to the Tropics, the 2024 winter cohort of FCS projects fills information gaps to produce actionable insights

Quantifying large greenhouse gas emissions from a retrogressive thaw slump in Alaska

Lead: Jennifer Watts
Collaborators: Kyle Arndt, Patrick Murphy

Retrogressive thaw slumps (RTS) are extreme permafrost thaw landscape features, which occur when a section of ice-rich permafrost becomes warm enough to cause the ground ice to melt and soils to collapse. Once they start, RTS continue to expand and destroy nearby permafrost for months to years. Many RTS have been identified, but because they are often in extremely remote arctic locations, very little is known about the potentially substantial carbon emissions from RTS in the form of carbon dioxide and methane. This study will provide the first continuous measurements of carbon emissions from a RTS, collected over at least a year via an eddy covariance tower. The research is also supported by an equipment loan provided through the U.S. Department of Energy AmeriFlux Rapid Response program, which recognized this project as a valuable opportunity to advance science. The data collected will also serve as a “proof of concept” for a subsequent $1.3M proposal to the National Science Foundation for continued research at the site.

Assessing the impacts of ecosystem disturbance on carbon emissions from Arctic and Amazon ponds

Lead: Elchin Jafarov
Collaborators: Zoë Dietrich, Andrew Mullen, Jackie Hung, Marcia Macedo, Kathleen Savage

Freshwater ecosystems are significant sources of the greenhouse gases that persist in the atmosphere and contribute to warming. However, research is lacking an understanding of how disturbances like wildfire and agriculture can change these emissions. This project will address these information gaps by collecting measurements of carbon emissions from ponds, using autonomous floating chambers developed with funding from a previous FCS grant. With this new high-resolution data, the team will unlock the ability to predict year-round greenhouse gas emissions from ponds in the Arctic and the Amazon. Floating chambers will be deployed in ponds in Alaska affected by wildfires, and in agricultural reservoirs in the Amazon-Cerrado frontier. In both locations, the ability to take more frequent measurements of carbon emissions will help researchers improve models and better assess the ponds’ impacts on regional carbon budgets.

The Polaris Project: Data synthesis from almost two decades of research and student participation

Lead: Nigel Golden
Collaborator: Sue Natali

Established in 2008, the Polaris Project has earned global recognition for its leadership in Arctic research, education, and outreach. Through the commitment to providing students with hands-on experience, Polaris has enabled numerous publications and presentations. Polaris is approaching a critical juncture in the next funding cycle, and this project will complete the first-ever comprehensive synthesis of Polaris Project research to help sustain Woodwell Climate’s sole undergraduate research program. By consolidating past research and educational achievements, the team will create a data synthesis paper to be submitted to a peer-reviewed, open-access scientific research journal, as well as a retrospective analysis of undergraduates’ research experiences with Polaris to be submitted to an education research journal. The team will also launch an online communications piece that documents past Polaris participants’ field experiences and unique journeys with a variety of narrative and artistic communications styles and elements.

Determining the climate sensitivity of coastal rivers to guide ecosystem restoration across SE Massachusetts

Lead: Abra Atwood
Collaborators: Marcia Macedo, Chris Neill, Linda Deegan, Scott Zolkos

Coastal rivers, like those that flow into Massachusetts’ Buzzards Bay and Vineyard Sound, are fragile environments that serve critical ecological functions for native fish, downstream estuaries, and coastal wetlands. Different rivers are uniquely sensitive to changes in air temperature based on a variety of characteristics, such as their water source or shade. However, land use changes, including housing development and cranberry bogs, have affected key river characteristics and stream temperatures. This project will investigate MA coastal rivers’ sensitivity to changing air temperature, as well as how that sensitivity is affected by both connection to groundwater and the creation or restoration of cranberry bogs. The temperature sensors and geochemical analyses used in this research may be scalable beyond these rivers and yield insights to inform research approaches relevant to rivers around the world.

A drought early warning system for the DRC: Developing a seasonal forecast based on novel machine learning approaches

Lead: Carlos Dobler-Morales
Collaborators: Christopher Schwalm, Glenn Bush

Seasonal weather forecasts hold immense potential to improve risk management from agricultural failure, water stress, and extreme events. However, significant advances in technical forecasting capabilities remain largely unavailable to communities without the resources to develop or customize them for their region. In 2023, Woodwell Climate Just Access co-produced a national climate risk assessment with the Democratic Republic of Congo’s Ministry of Environment and Sustainable Development. That report identified drought as a major climate threat to the DRC—one which stands to affect almost the entire country. In response, this project will develop a seasonal drought forecasting model tailored to the DRC using cutting-edge machine-learning methods. The forecast will be able to deliver precise rainfall anomaly predictions up to six months in advance for the whole country, and serve as an early warning system to help local people and decision-makers anticipate the impacts of escalating drought risk.

 

Learn more about the Fund for Climate Solutions.

A recent paper, led by Woodwell Climate postdoctoral researcher Dr. José Safanelli, revealed that Brazil’s farms have been steadily moving out of the most suitable regions for agriculture—opening up a significant portion of the world’s agricultural production to vulnerability from the changing climate. 

The study, published in Applied Geography, used an index to assess “Grain-cropping suitability” for two key staple crops—soy and maize.  Suitability was determined by climatic factors (temperature and precipitation), as well as soil quality and terrain. The result was a continuous map detailing the areas of the country with the best biophysical conditions for growing crops.

Overlaying land use change data from the past two decades with this new map revealed a historical trend of agricultural lands expanding towards areas with poorer soil quality and lower suitability for grain-cropping, primarily in the north central and northeastern portion of the country.

Understanding Brazil’s agricultural migration

Farmers in Brazil have been moving north to this “agricultural frontier” since the 1980s— drawn primarily by economic opportunity, as well as the higher quality climate and terrain conditions along the southern edge of the Amazon.

Despite the favorable climate, the soil is inferior. Farmers are seeking cheap land, which often comes in the form of degraded pasture, originally created by clearing forest. Rainforest soils are not naturally nutrient rich and, without any additional inputs, the soil quality becomes depleted after just a few years. Many farmers know this fact, but come anyway. Dr. Safanelli has even seen this trend unfold within his own family.

“I was born in the south of Brazil, a region that has good soil conditions. Recently, two of my uncles who are farmers emigrated to Mato Grosso. There, the climate is wetter and more stable, but the soils are poor—depleted of nutrients.”

Additional research by Woodwell Climate Assistant Scientist Dr. Ludmila Rattis suggests that climatic advantage may be short-lived. Her work indicates that the climate in these areas is changing— becoming drier and hotter as global temperatures rise—and deforestation for agricultural expansion just makes the problem worse. 

“We showed in our paper that these places have good climate and terrain suitability for now,” says Dr. Safanelli. “But they are restricted in soil quality. In Mato Grosso—the largest agricultural production state in Brazil—for example, the climate has been more stable and favorable than in other parts. The problem is that, according to projected climate scenarios, climate change may push these areas out of a good suitability space.”

What this means for agriculture in Brazil

Brazil is currently the world’s top producer of soy, and in the top three for maize. But this expansion into lower-suitability regions has introduced greater vulnerability into the agricultural system. Farmers already must provide greater investment in fertilizing the soil to make it productive, which cuts into their margins for profit. Add to that the fact that poor-quality soils, typically low in organic matter, can make crops less resilient to extreme heat and drought.

“Crop evapotranspiration—a process that directly governs crop growth and yield—depends on soil for absorbing rainfall and storing water. These marginal soils can make farmers more susceptible to climate change’s expected drier and warmer conditions, as they have limited capacity for storing water,” says Dr. Safanelli.

Reducing these vulnerabilities, Dr. Safanelli says, will require an integrated approach— improving land management practices and increasing crop yields on existing land to reduce the pressure to expand. “Reducing the vulnerability of croplands may be possible by adopting management practices that increase the resilience of the farming system, such as fully incorporating the principles of conservation agriculture, integrated production through agroforestry, crop-forest-livestock systems, or irrigation to control dryness. And perhaps allocating some of these marginal lands for land restoration, concentrating our resources in more highly suitable croplands.”