Pantanal: Biome most affected by rising temperatures in Brazil
The temperature rise in the Pantanal and Amazon biomes is among the highest in the country over the past 40 years, according to data released by MapBiomas this Wednesday (Nov. 5). The two regions recorded average increases of 1.9°C and 1.2°C, respectively.
Using satellite imagery and data modeling, the new MapBiomas Atmosphere platform provides information on temperature and precipitation variations from 1985 to 2024, and on air pollutants from 2003 to 2024, covering the entire Brazilian territory.
Across the country, the survey shows that temperatures rose at an average rate of 0.29°C per decade. Over the period studied, the total increase reached 1.2°C. However, the rate of warming varies between biomes.
In the Pantanal, temperatures increased by 0.47°C per decade, and in the Cerrado by 0.31°C per decade - both in the most continental part of the country. The Amazon saw an increase of 0.29°C per decade. Coastal biomes, on the other hand, warmed more slowly: Caatinga, +0.25°C per decade; Atlantic Forest, +0.21°C per decade; and Pampa, +0.14°C per decade.
“The data reveal that, systematically, temperatures have been rising throughout Brazil since 1985. Last year set a record, but it is not an isolated case,” explains Luciana Rizzo, professor at the Atmospheric Physics Laboratory of the University of São Paulo (USP) and member of MapBiomas Atmosfera.
The record the researcher refers to was calculated based on temperatures registered in the Amazon and Pantanal in 2024. Over the past 40 years, the average temperature in these two biomes was 25.6°C and 26.2°C. Last year, these figures increased by 1.5°C and 1.8°C, respectively. This was the highest annual increase recorded since 1985. According to Rizzo, these data corroborate the occurrence of extreme events, such as the unprecedented fires and drought that affected the Amazon and Pantanal last year.
According to MapBiomas, the data show that in the more continental states, such as Mato Grosso do Sul, Mato Grosso, and Piauí, temperatures are rising more rapidly, at rates between 0.34°C and 0.40°C per decade. Coastal states tend to have lower warming rates, such as Rio Grande do Norte, Alagoas, and Paraíba (0.10°C to 0.12°C per decade). In the metropolitan region of São Paulo, the rate of increase is 0.19°C per decade.
Deforestation and high temperatures
The general coordinator of MapBiomas, Tasso Azevedo, states that the Amazon has lost 52 million hectares of native vegetation since 1985, equivalent to a 13 percent reduction.
“During the same period, the biome experienced an average temperature increase of 1.2°C. Recent studies indicate that forest loss alters the exchange of heat and water vapor with the atmosphere, resulting in higher temperatures,” he explains.
A study cited by MapBiomas and published in Nature Geoscience showed that deforestation accounts for 74 percent of the reduction in rainfall and 16 percent of the temperature increase in the Amazon during the dry season. A drier climate, in turn, promotes the occurrence of fires, according to Luciana Rizzo.
“Air pollution in the North was more intense than in the heavily urbanized areas of the Southeast in 2024. Poor air quality in Amazonian states is directly linked to smoke from forest fires, which occur mainly during the biome’s dry season,” says the researcher.
In 2024, rainfall in the Amazon was 448 millimeters (mm) below the historical average, or 20 percent less. In some parts of the biome, the precipitation deficit reached 1,000 mm per year. The decrease in rainfall contributed to the expansion of the burned area in the Amazon, which reached 15.6 million hectares last year.
Changes in average temperatures affect all Brazilian biomes. The Pantanal, where temperatures have risen 1.9°C over the past 40 years, is fed by rainfall from the Upper Paraguay Basin, which in 2024 recorded 314 millimeters (mm) below average - with 205 days without rain. “The reduction in precipitation also has significant effects, especially in the Amazon and the Pantanal,” adds Rizzo.
Paulo Artaxo, a professor at USP and member of MapBiomas Atmosfera, believes the platform can help preserve the country’s ecosystems.
“It is a new tool that helps Brazil implement public policies based on empirical evidence and indicates which regions would be most affected by climate change and land-use change,” emphasizes Artaxo.
