- An unprecedented study analyzed data from 1991 to 2023 and found that each 0.1°C increase in average global air temperature led to 360 new climate disaster events and damages in Brazil amounting to R$ 5.6 billion ($970 million).
- The global warming process has accelerated over the current decade, resulting in an average of 4,077 recorded climate-related disasters per year in Brazil, compared to 725 per year during the 1990s — an increase of 460%.
- The extreme events recorded over the period — totaling 64,280 — include droughts, floods and storms in 5,117 Brazilian municipalities; over 219 million people were affected, 78 million of whom during the last four years.
- Despite the increased number of disasters and the damage they caused, Brazil’s federal budget for risk and disaster management has been cut every year between 2012 and 2023 by an average of R$ 200 million ($34.6 million) per year.
It’s a proven fact: the relationship between rising global temperatures and the number of climate-related disasters is directly proportional.
From 1991 through 2023, each rise of 0.1°C in the average global air temperature led to 360 new records of climate-related disasters in Brazil, including severe droughts, flooding and storms. The consequential rise in the ocean’s surface temperature led to 584 new cases. There was an average increase of 100 new extreme events per year in Brazil over the period and subsequent economic losses amounting to some R$ 5.6 billion ($970 million) for each 0.1°C rise in average global temperature. The process has accelerated this decade, with 4,077 disasters recorded per year on average. During the 1990s, this number was a mere 725, meaning there has been a 460% increase since then.
These unprecedented data are from the study entitled “2024 – The Hottest Year in History,” carried out by the Brazilian Ocean Literacy Alliance, a group of multiple organizations focused on work related to the Ocean Decade. The project is coordinated by the Sea of Science Program at Brazil’s São Paulo Federal University (UNIFESP), the Ministry of Science, Technology and Innovation, and by UNESCO. It is funded by the Boticário Group Foundation and other NGOs. The study is the first volume in the series entitled “Brazil in Transformation: The impact of the Climate Crisis.”
The collection offers visual and educational information on a complex and often misunderstood topic. “When you talk about climate change, it seems like a far-off or difficult topic. Now we know how much each 0.1°C represents in terms of increased loss, more disasters and the increasing number of lives that are impacted. It makes rising temperatures more tangible,” says Janaína Bumbeer, a co-author of the study and project coordinator at the Boticário Group Foundation. “We’re not talking about natural disasters anymore, the ones that are part of the natural cycles we’re used to. We are talking about climate disaster, which involves human impact.”
During the 32-year period that the researchers studied, 64,280 climate-related disasters occurred in 5,117 Brazilian municipalities, or 92% of all municipalities. Half of the disasters recorded were droughts, while flooding, torrential rains and high water levels composed 27% of the total. Storms composed 19%. More than 219 million people were affected by death, displacement, homelessness and illness. 78 million of these people were affected during the last four years.
Economic losses have also grown over the decades, totaling R$ 547.2 billion ($94.8 billion) between 1995 — the first year of these data — and 2023. The average annual loss since 2020 has been R$ 47 billion ($8.14 billion) per year, more than double the annual average during the previous decade, which was R$ 22 billion ($3.8 billion) per year.
This is the first Brazilian study to directly link climate-related disaster records and their resulting economic damage with changes in global temperatures with the aim of projecting scenarios and creating prevention strategies. The methodology used was to cross data from the government’s Integrated Disaster Information System Platform (S2ID) detailing disasters that have occurred in Brazil and the resulting damages with global temperature data from the University of Maine’s Climate Reanalyzer site.
“The idea was to understand how urban growth and the use of natural resources has impacted the environment, and how people are suffering because of climate change,” says Aline Martinez, a UNIFESP researcher and coordinator of the study.
The hottest year in history
2024 was the hottest year on record. Last year’s average temperature surpassed pre-industrial levels by 1.6ºC for the first time in history, according to the 2024 global climate highlights report released in early January 2025 by European agency Copernicus. The Paris Accord had set the limit at 1.5ºC to reduce the risk of climate change impacts.
Extreme events were partially the result of record-high global greenhouse gas levels and of higher air and ocean surface temperatures. In Brazil, 60% of the national territory experienced record droughts, which led to more wildfires in Amazonia, the Cerrado and the Pantanal. Nearly 95% of the municipalities in the state of Rio Grande do Sul were affected by its most extreme flooding in history.
Droughts in Brazil were intensified by El Niño, a global climate condition that normally heats surface water in the equatorial Pacific Ocean to higher levels than normal every two or seven years, provoking global climatic impacts. In turn, El Niño is now intensified by global warming, which worsens the oceanic “feverish state” and, consequently, the phenomenon’s impacts. This is one important point raised by the study, because climate changes are directly linked to the ocean.
“The ocean plays a fundamental role in climate regulation, acting as a carbon sink. It absorbs a large amount of heat from the atmosphere and regulates many processes. Until a certain point in our history, it just accumulated carbon dioxide, but now it is heating up as a result. So, everything we are seeing in terms of climate intensification or alterations are direct reflections of changes in the ocean,” explains Martinez.
Urgent measures
The growing impacts of the climate crisis have reinforced the urgency of finding measures to mitigate their effects and make Brazil more resilient socially and economically, say the researchers. They start by talking about reducing greenhouse gas emissions: “One of our greatest problems is carbon emissions. Cities, whether they are located on the coast or not, can develop their own plans to reduce emissions and restore natural environments, which also serve as carbon sinks,” says Martinez. Forests, mangroves, sandbanks, Cerrado vegetation and coral reefs are examples of natural areas that need to be protected and allowed to expand.
“The study provides a very accurate assessment of the risk brought by global warming,” according to climatologist Carlos Nobre, who was not part of the study According to Nobre, climatologists expected El Niño to bring a rise of 1.3°C in the average global temperature in 2023, but it suddenly jumped to 1.5°C.
“Hundreds of scientists are trying to explain why the temperature has exploded,” says Nobre. “No one knows if it will stay this hot during the next two years, but if it does, we will probably have reached the 1.5°C limit, which should not be exceeded until 2050 according to the Paris Accord. If the science indicates that we have reached that mark, we will have to accelerate emissions reduction.”
Nobre is categorical: if we only achieve zero emissions by the middle of the century, we will reach an average increase of 2.5°C or more by then, sentencing all biodiversity, including the human species, to ecological suicide. Increased investments to combat climate change focusing on adapting cities will be essential to contain the advance of the crisis.
But the opposite has been happening in Brazil, where resources allocated to prevention and mitigation fell by an average of nearly R$ 200 million ($34.6 million) per year between 2012 and 2023, according to the study. The R$1.7 billion ($294.6 million) federal budget for risk and disaster management for 2025 follows the same trend compared to 2024.
The study goes on to show that there has always been more spent on emergency management than on prevention strategies. It suggests that the development of risk reduction and prevention plans — including monitoring, mapping of risk areas, issuing of alerts and education — combined with planning for climate adaptations would reduce spending in emergencies. According to the UN, every dollar invested in risk reduction and prevention can save up to $15 in post-disaster recovery.
“The data show that immediate and ambitious action must be taken. It is important that we increase investment and have strong environmental policies so that we can have a stronger economy,” says Bumbeer. “Climate change and disasters will continue to occur, so we have to work on adaptation and invest in nature-based solutions, increasing the amount of preserved area. With the Climate Plan, which will provide major guidelines for different sectors, municipalities will be able to incorporate these guidelines according to their realities and create their own plans for climate adaptation including policies and tools to increase investment.”
Five more volumes will be added to the series of technical journals throughout 2025, to be published on the Sea of Science website. The next three will cover different climate disaster categories in detail: storms and heavy rains; cyclones and strong winds; and droughts and wildfires. The fifth edition will detail regional disaster scenarios and the sixth will be about solutions.
Banner image: Flooding in the historic center of Porto Alegre, Rio Grande do Sul, in 2024. Image by Rafa Neddermeyer/Agência Brasil.
This article was first published here in Portuguese on Jan. 23, 2025.
Credits
