The Amazon rainforest, recognized as the largest rainforest on Earth, has experienced a significant decline in precipitation due to local deforestation and global climate change. A recent study reveals that local deforestation is responsible for nearly an 8% decrease in rainfall during dry seasons since 1985, equating to a loss of approximately 21 millimeters of rain. This research, published in Nature Communications, highlights the urgent need for action to preserve this critical ecosystem.
Researchers from Brazil and the Max Planck Institute for Chemistry in Germany conducted an extensive analysis of the Amazon region, focusing on the distinct impacts of rising global temperatures and local deforestation. According to Luiz Machado, a climate researcher at the University of São Paulo, “Deforestation accounts for almost 75 percent of the decline in rainfall. Even small changes in rainfall during the dry season could therefore have a disproportionate impact on vegetation health.” During the dry season, only 26 percent of the average annual precipitation occurs, totaling 281 millimeters compared to 1,097 millimeters during the rainy season.
The study also indicates that deforestation contributes about 16% to the observed increase of 2°C in temperature, while a significant 84% of this rise is attributed to global climate change. The researchers found that the relationship between deforestation and climate change impacts is not linear, noting that the most significant changes occur when 10% to 40% of the forest is lost.
Critical Findings on Emissions and Future Climate
The research team analyzed data from 29 regions within the Brazilian Amazon, gathered over 35 years (1985 to 2020) using advanced satellite technology and atmospheric measurements. Through specialized statistical techniques, they effectively distinguished the effects of deforestation from those of global climate change. The findings show that over 99% of the rise in greenhouse gases such as methane and carbon dioxide is due to global climate change, while deforestation accounts for a mere 0.3% of the increase in CO2.
Looking ahead, the study projects the climate of the Amazon in 2035. Christopher Pöhlker from the Max Planck Institute states, “If deforestation continues at the current rate, our data indicate that we can expect a further temperature rise of about 0.6°C and a significant decrease in precipitation of about seven millimeters during the dry season compared to today. This will certainly put additional stress on the forest.”
The researchers emphasize that the Amazon rainforest is undergoing a critical transformation, likely exacerbated by extreme weather events, such as the extraordinary drought that occurred in 2023. While the exact threshold of deforestation that could lead to the collapse of the Amazon ecosystem remains uncertain, the complex interactions between climate change and deforestation highlight the need for immediate intervention to safeguard this vital environmental resource.
In summary, the findings from this extensive research underscore the urgent necessity of halting further deforestation to maintain the climate resilience of the Amazon region and mitigate the impacts of global climate change.
