Text: Luciana V. Gatti (Translation: Natália Juliano)
Over the course of 21 years of research in the Amazon—measuring CO₂ (carbon dioxide), CO (carbon monoxide), and other greenhouse gases, as well as analyzing the forest's gas emissions and absorption, including those caused by wildfires—we have identified a clear correlation between deforestation, reduced rainfall, rising temperatures, and increased CO₂ emissions. Reaching this conclusion took 14 years of data collection, more than 1,000 flights using small aircraft, and research conducted across four strategically selected locations that represent the Amazon ecosystem.
Aiming to understand the significant variation observed from year to year and between different regions, we investigated why some areas of the forest showed emission statistics that differed so markedly from others. To do this, we analyzed 40 years of data on rainfall, temperature, and deforestation for each region. The results revealed that increased deforestation in a given area intensifies climate stress, leading to longer and more severe dry seasons. This, in turn, reduces the region’s capacity to absorb carbon—particularly during the months of August, September, and October, when oceanic humidity levels are at their lowest.
The current dry season is a result of intensified deforestation since 2019—not only in the Amazon rainforest but across all Brazilian ecosystems. From that year onward, we have witnessed an increase in extreme weather events, including both heavy rainfall and severe droughts, throughout the country. Nature—its forests, jungles, and vegetation—plays a vital role in climate regulation. The ongoing loss of these ecosystems accelerates climate change in Brazil and contributes to global warming. In the current context, where human-induced wildfires are occurring more frequently during drought seasons, we are witnessing widespread vegetation loss. This trend is expected to lead to an exponential increase in extreme weather events in the near future, raising serious concerns within the scientific community.
The surge of wildfires currently affecting Brazil is not a natural phenomenon. Naturally occurring fires may be ignited by lightning strikes or accidents, such as discarded cigarette butts or electrical sparks. However, such incidents do not occur simultaneously across the entire country—they are provoked. Wildfires in Brazil intensified after July 15, 2024, particularly in the Amazon and Pantanal regions. Within a month, the number of fire hotspots reached 155,000. In the past 30 days alone, 105,665 hotspots were recorded—68% of the total concentrated in just one month. The seven days with the highest number of wildfires are presented in Table 1, which also highlights the three states with the greatest number of fire outbreaks.
The most affected ecosystem is the Amazon, as shown in Figure 2. Its forests face the highest wildfire risk due to widespread deforestation, which intensifies droughts. This local degradation is compounded by global climate conditions, further worsening the scenario.In 2023, the El Niño phenomenon and abnormally high temperatures in the North Atlantic Ocean played a major role. Although El Niño is not present this year, ocean temperatures remain elevated, continuing to exert pressure on the climate. Combined with ongoing deforestation, this results in reduced rainfall and rising temperatures across the region.
Luciana V. Gatti states: “On September 15, 2024, during an interview with the Brazilian news channel GloboNews, I was asked about the wildfires and was preparing to comment on the widespread, large-scale fires occurring across Brazil. This immediately brought to mind the 'Day of Fire' on August 10, 2019, when fires spread throughout the Amazon and, days later, dark rain fell over São Paulo. To discuss the impact on ecosystems, I began with my home state, São Paulo, which recorded a shocking 1,886 fire hotspots in a single day—August 23, 2024. I recalled my time living in Ribeirão Preto and São Carlos, where it was once common to see soot rain during the sugarcane harvest season. Fortunately, burning cane is no longer practiced, to the relief of the hundreds of thousands of residents and their lungs.
Luciana adds: “At no point did I feel guilty about my statement—nor could I—because our research methods are grounded in data: the number of wildfire hotspots and the emissions they produce. We do not assign blame or responsibility to specific natural persons or legal entities. I did not mention the name of the National Institute for Space Research (INPE), where I work as a scientist. I was simply developing my reasoning based on the findings of 25 years of research, when the hotel’s Wi-Fi connection suddenly dropped. I was highlighting the fact that Governor Tarcísio (of São Paulo) announced financial compensation prematurely, without first properly identifying those responsible and the actual victims. All victims deserve compensation—from large landowners to smallholders, as well as families who became ill or lost loved ones. It is regrettable that the Secretary of Agriculture for the State of São Paulo chooses to label a scientist as a criminal instead of working to identify the real criminals—those responsible for the 1,886 wildfire hotspots recorded in São Paulo state on a single day, August 23, 2024. When combined with the incidents between August 22 and 24, the total reaches 2,621 hotspots.”
We need to protect ourselves from climate change: plant trees, plant trees, and plant trees. As “rainmakers,” trees help reduce temperatures and shield us from heat waves and extreme weather events such as torrential rainfall. They also capture CO₂ from the atmosphere—the leading driver of climate change.
The current situation makes it clear that our economic model—centered on the export of grains, meat, and timber—leaves us increasingly vulnerable to climate change and extreme events that are taking the lives of Brazilians. We urgently need to develop an economic system that is viable under our current climate conditions. One solution is to produce food through agroforestry systems, which can be both productive and sustainable, generating rainfall and helping regulate temperatures. Today, we must come together to create real solutions. We need to stand against groups that disregard the public good. We must learn how to survive in a country, and world, that are becoming uninhabitable due to the relentless attacks on the environment.
References
Gatti, L. V., Basso, L. S., Miller, J. B., Gloor, M., Gatti Domingues, L., Cassol, H. L. G., ... & Tans, P. (2021). Amazonia as a carbon source linked to deforestation and climate change. Nature, 595(7867), 388–393. https://doi.org/10.1038/s41586-021-03629-6
Gatti, L. V., Basso, L. S., Domingues, L. G., Cassol, H. L. G., Miller, J. B., Gloor, M., ... & Tans, P. (2023). Increased Amazon carbon emissions mainly from decline in law enforcement. Nature, 621, 318–323. https://doi.org/10.1038/s41586-023-06390-0
Gatti, L. V., Gloor, M., Miller, J. B., D'Amelio, M. T. S., Martinewski, A., Basso, L. S., ... & Tans, P. (2014). Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements. Nature, 506(7486), 76–80. https://doi.org/10.1038/nature12957