Climate change in Brazil is causing higher temperatures and longer-lasting heatwaves, changing precipitation patterns, more intense wildfires and heightened fire risk. Brazil's hydropower, agriculture and urban water supplies will be affected. Brazil's rainforests, and the Amazon, are particularly at risk to climate change. At worst, large areas of the Amazon River basin could turn into savannah, with severe consequences for global climate and local livelihoods. Sea levels in Brazil are predicted to rise by more than by the middle of the century. Extreme weather events like droughts, flash floods, and urban flooding are causing annual losses of around R$13 billion (US$2.6 billion), equivalent to 0.1% of the country’s 2022 GDP. Climate impacts could exacerbate poverty.
Brazil's greenhouse gas emissions per person are higher than the global average, and Brazil is among the top 10 highest emitting countries. Greenhouse gas emissions by Brazil are over 4% of the annual world total, firstly due to cutting down trees in the Amazon rainforest, which emitted more carbon dioxide in the 2010s than it absorbed, and secondly from large cattle farms, where cows belch methane.
In the Paris Agreement, Brazil promised to reduce its emissions, but the 2019-2022 Bolsonaro government has been criticized for doing too little to limit or adapt to climate change. In 2024 Brazil revised its Nationally Determined Contribution (NDC), setting a goal to cut emissions by 59% to 67% compared to 2005 levels by 2035.
Greenhouse gas emissions
Brazil's 2023 greenhouse gas emissions are estimated at 2.38 billion tonnes of equivalent, over 4% of the global total emissions. This makes Brazil the 6th highest emitting nation in 2023. Brazilians emit around 11 tonnes per person, compared to a global average of about 5 tonnes per person. , Brazil is the 4th heaviest cumulative emitter at 110 Gt.
In 2020, official figures were reported for 2016: agriculture 33.2%, energy sector 28.9%, land use, land-use change, and forestry (LULUCF) 27.1%. Industrial Processes and Product Use (IPPU) and waste contributed 6.4% and 4.5%, respectively.
According to the Brazilian Climate Observatory, the country emitted 2.17 billion gross tons of carbon dioxide equivalent (te) in 2019. Deforestation accounted for 968 million te, which was 44% of the total, agriculture emitted 598.7 million te (28%) and the energy sector 413.6 million te (19%), industry 99 million te (5%) and waste 96 million te (4%).
Although the government has pledged net zero emissions by 2050, critics complain that immediate action is not being taken. Researcher Emilio La Rovere, one of the coordinators of a report from 2013, said: "if nothing is done to restrict post-2020 emissions, Brazil may emit 2.5 billion tons of carbon dioxide as early as 2030. To give you an idea, the number exceeds the total for 2005, when emissions totaled around 2 billion tons."Carvalho, Eduardo. "Relatório diz que mudança do clima pode afetar alimento e energia no país". O Globo, 08/09/2013. In 2024 Brazil revised its Nationally Determined Contribution (NDC), setting a goal to cut emissions by 59% to 67% compared to 2005 levels by 2035.
Agriculture
Cattle
In 2012, Brazil had the second largest number of cattle in the world, with 205 million head.Berchielli, Telma Teresinha, Juliana Duarte Messana & Roberta Carrilho Canesin. "Produção de metano entérico em pastagens tropicais". In: Revista Brasileira de Saúde e Produção Animal, 2012; 13 (4) Cows are ruminants that emit greenhouse gases such as methane and nitrous oxide.
Deforestation
Trees are cut down to create fields for cattle and soya. Deforestation peaked in 2004, then decreased until the early 2010s. Since then, deforestation has tended to increase through 2020.
Fossil fuels
The largest single emitter in the energy sector is oil products used as fuel for transport in Brazil, but some natural gas and coal is burnt by the electricity sector in Brazil. In 2016/17, coal-fired power stations in Brazil received over 1 billion reals in subsidies. In the Convention on Biological Diversity, Brazil committed to phasing out environmentally harmful subsidies by 2020, but the government said in 2022 that coal power would be subsidized until 2040.
Impacts on the natural environment
Temperature and weather changes
According to José Marengo, of the National Institute for Space Research, recent studies show that, with the exception of stretches of the coast of Chile where there has been a slight cooling in recent decades, in all other areas of South America forecasts indicate an increase in temperature."Brasil pode ficar até 6°C mais quente em 2100, diz relatório" . PBMC, 2011.
The Amazon has a prominent role in regulating the climate throughout Brazil and other regions in South America. Its forest is a major carbon sink and is essential for the formation of the rains that irrigate much of the country.Painel Brasileiro de Mudanças Climáticas. Sumário Executivo do Volume 1 – Base Científica das Mudanças Climáticas . Contribuição do Grupo de Trabalho 1 para o 1º Relatório de Avaliação Nacional do Painel Brasileiro de Mudanças Climáticas [Ambrizzi, T., Araújo, M., Silva Dias, P.L., Wainer, I., Artaxo, P., Marengo, J.A., 2012. According to Marengo et al., 30% to 50% of the rainfall in the Amazon Basin originates in the forest itself through evaporation. "In addition, the humidity originated in the Amazon Basin is carried by the winds to other parts of the continent and is considered important in the formation of precipitation in regions distant from the Amazon itself."Centro de Ciência do Sistema Terrestre do Instituto Nacional de Pesquisas Espaciais / Met Office Hadley Centre [Marengo, Jose A. (coord.)]. Riscos da Mudanças Climáticas no Brasil: análise conjunta Brasil-Reino Unido sobre os impactos das mudanças climáticas e do desmatamento da Amazônia, 2011, pp. 17–18. Naturally, if the forest disappears, the rains will disappear. A vicious circle is created in which if deforestation exceeds a certain critical level, estimated at losses of 40%, the forest will be unable to generate enough rain to maintain itself: the less forest, the less precipitation, and the less precipitation, the less forest. About 19% of the Amazon forest has already been lost,Santos, Daniel; Pereira, Denys & Veríssimo, Adalberto. O estado da Amazônia: uso da terra. Instituto do Homem e Meio Ambiente da Amazônia, 2013, p. 16 and recent studies indicate that it is close to passing the critical point, beyond which its degradation will become irreversible.Lovejoy, Thomas E. & Nobre, Carlos. "Amazon Tipping Point". Editorial. In: Science Advances, 2018; 4 (2)Nobre, Carlos et al. "Land-use and climate change risks in the Amazon and the need of a novel sustainable development paradigm". In: PNAS, 2016; 113 (39): 10759-10768Veiga, Edison. "Degradação da Amazônia já chegou a ponto irrecuperável, diz estudo". Deutsche Welle, 10/01/2020 (entrevista com o autor principal do estudo Brando, P. M. et alii. "The gathering firestorm in southern Amazonia". In: Science Advances, 2020; 6 (2) In addition to the problems in the Amazon, all other national biomes – the Cerrado, the Semi-Arid, the Pantanal, the Atlantic Forest and the Pampa – also suffer important effects, most of them with an increasing tendency, contributing to amplify the cascading effects.Comitê Interministerial sobre Mudança do Clima. Plano Nacional sobre Mudança do Clima , 2008.Sá, Iêdo Bezerra; Riché, Gilles Robert & Fotius, Georges André. "As paisagens e o processo de degradação do semi-árido nordestino". In: Silva, José Maria Cardoso da e t al (orgs.)]. Biodiversidade da caatinga: áreas e ações prioritárias para a conservação. Ministério do Meio Ambiente / Universidade Federal de Pernambuco, 2003, pp. 17–36UNEP. Global Environment Outlook 4: environment for development, 2007.Centro de Sensoriamento Remoto. "Monitoramento do Bioma Cerrado". In: Monitoramento do Desmatamento nos Biomas Brasileiros por Satélite. Acordo de Cooperação Técnica MMA/Ibama, ago/2011.Tabarelli, M. et al. "Espécies Ameaçadas e Planejamento da Conservação". In: Galindo-Leal, C. & Câmara, I. B. (orgs). Mata Atlântica: Biodiversidade, ameaças e perspectivas. SOS Mata Atlântica / Conservação Internacional, 2005, pp. 86–04Núcleo do Bioma Caatinga. "Monitoramento por Satélite do Desmatamento no Bioma Caatinga". Ministério do Meio Ambiente, 2010."MMA divulga dados do monitoramento do desmatamento de três biomas". Sala de Imprensa – Ibama, 09/02/2012."Estudo aponta maior impacto de desmatamento na parte alta da Bacia do Alto Paraguai". WWF-Brasil, 25/05/2010Ministério da Ciência, Tecnologia e Inovação [Lima, Ricardo da Cunha Correia; Cavalcante, Arnóbio de Mendonça Barreto; Marin, Aldrin Martin Perez (eds.)]. Desertificação e Mudanças Climáticas no Semiárido Brasileiro. Instituto Nacional do Semiárido, 2011.
Another important part of the Brazilian rains comes from the circulation of ocean moisture. Global warming also has an impact on ocean currents that influence the Brazilian climate, and the winds that carry the humidity that reaches Brazil are having their patterns modified, with the effect of reducing the level of atmospheric humidity and disturbing the formation of clouds, reducing precipitation. Reducing rainfall, in turn, can dry underground aquifers. These combined factors mean, in total, a generalized reduction in the availability of water and drier environments in most of the nation.Centro de Ciência do Sistema Terrestre do Instituto Nacional de Pesquisas Espaciais / Met Office Hadley Centre, pp. 17–18; 48–49.Pivetta, Marcos. "Extremos do clima" . In: Pesquisa FAPESP, ago/2013; (210). In some regions, however, due to different mechanisms, rainfall is expected to increase, also bringing adverse effects."No Brasil, aquecimento global significará mudança no padrão de chuvas" . PBMC, 2011. According to the PBMC, "the change with the greatest impact will be a change in rainfall patterns. Research shows that in the south and southeast, regions that suffer from floods and landslides, rains will become stronger and more frequent. In the northeast, the trend is the opposite.
Projections of the First National Assessment Report on Climate Change (2012)
In the executive summary of the 1st PBMC Report, the limitations of the study are highlighted. Because some projections were made based on incomplete data, there is some uncertainty about the conclusions. Despite this,
"In general, the results of the models managed to capture the behavior of the present climate very well and, thus, despite the uncertainties, the projections of future climate changes throughout the 21st century are plausible. Therefore, such projections constitute innovative and valuable information both for the purpose of mitigation, as well as the planning of adaptation and minimization of impacts and vulnerability actions with the set of inhabiting society in different Brazilian biomes. Taking into account the different projections that imply potential impacts on natural and human systems (socioeconomic and environmental), it is already possible to analyze the expected impacts of climate change in the various sectors of Brazil, and the planning and decision making to define adaptation strategies and mitigation policies."