Climate change in Brazil


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 20cm 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, 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, 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 27.1%. Industrial Processes and Product Use 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 in 2019. Deforestation accounted for 968 million te, which was 44% of the total, agriculture emitted 598.7 million te and the energy sector 413.6 million te, industry 99 million te and waste 96 million te.
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." In 2024 Brazil revised its Nationally Determined Contribution, 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. 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.
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. 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." 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, and recent studies indicate that it is close to passing the critical point, beyond which its degradation will become irreversible. 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.
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. In some regions, however, due to different mechanisms, rainfall is expected to increase, also bringing adverse effects. 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,
For the Semi-Arid-Caatinga, an increase of up to 4.5 °C in air temperature and a reduction of up to 50% in rainfall are predicted. The environment, naturally very dry and with sparse vegetation, can partially become desert. For the Cerrado the disturbances would be similar, with an increase in temperature of up to 5.5 °C and a decrease of up to 45% in rainfall. The Cerrado today concentrates most of the agricultural activities in Brazil. The Pantanal would also be very affected, with up to a 4.5 °C increase and up to 45% less rain. In the Atlantic Forest, the climate would stay up to 3 °C warmer and up to 30% rainier. For Pampa, there would be up to 3 °C increase in temperature averages, and rains up to 40% above normal.
Not only will precipitation totals change, it may start to occur in more erratic and violent patterns, with more intense and prolonged droughts and more severe and frequent flooding episodes, varying in different regions. According to the report, "the scenarios point to a decrease in rainfall in the winter months across the country, as well as in the summer in eastern Amazonia and the Northeast. In contrast, the country could experience an increase in the frequency and intensity of intense rain in the subtropical region and in the extreme west of the Amazon." Changes in the levels and availability of groundwater are also foreseen.

Sea level rise

Measurements on the coast of São Paulo indicate that sea level has risen 30 cm in the last century, surpassing the world average, and there are already many signs of coastal erosion, groundwater is gradually salted, the hangovers become higher, causing damage to the infrastructure of coastal cities. Twenty beaches are in danger of disappearing. In Recife, the famous Boa Viagem beach lost some sections swallowed by the sea, and Olinda lost 59% of its strip of sand between 1995 and 2010.

Ecosystems

Brazil's ecosystems will be impacted by temperature changes and rainfall changes. In the projections of the 1st Report, by the end of the 21st century, the Amazon may experience a reduction of up to 45% in rainfall, and an increase in the average temperature of up to 6 °C. This comes close to the worst scenarios foreseen by the Intergovernmental Panel on Climate Change, which predicted important changes in most of the biome. However, the impact of deforestation was not considered in the assessment, which will certainly increase the levels of variation to some extent. The evolution of the future scenario will depend on the country's success in managing the serious threats to the biome. After a decade-long trend of reduced deforestation rates, recent years have documented a rapid increase in destruction of trees. A report estimated that if 40% of the forest disappears, droughts will increase and turn much of the forest into savanna. This will result in a drastic reduction in biodiversity and will also have a negative effect on the amount of rain Brazil can expect.