Since the 1960s more than 10% of the Amazon rainforest trees have been cut, according to scientists at the University of Edinburgh. The increase in CO2 (carbon dioxide) in the atmosphere has led to a rise in climate change potential. Mathew and Jean-Francois Exbrayat, both from the University’s School of GeoSciences, reported in Geophysical Research Letters, that Amazon deforestation accounted for approximately 1.5% of the rise in carbon dioxide (CO2) levels between the middle of the th Century and the present. The increase in total carbon was only marginally greater than that caused by fossil fuel emissions. If deforestation by humans had not happened, the Amazon rainforest might be 12% more green than it is now. (Image: knowledge.wharton.upenn.edu) Carbon storage According to the authors, theirs is the first study to show the extent of deforestation in the Amazon by determining what impact human activity has had on its ability to store carbon. If deforestation had not taken place, the Amazon rainforest today would have 12% greater vegetation and would be much larger. To grow trees, they need carbon dioxide (CO2) to survive. They absorb large amounts of carbon dioxide from the air. It helps reduce the climate change rate and offsets the effects of fossil fuel emissions. Modeling deforestation Williams, Exbrayat and their colleagues created maps that showed how large the Amazon rainforest would look today if it wasn’t for human activities. The first high-resolution satellite photos were available in 2000,, so researchers created virtual models to determine how the forest had changed over the past decade. These models were used to examine how loss of trees affected the Amazon’s capacity to absorb carbon. Trees are carbon-dioxide consumers and reduce human-induced global warming. Image: fs.fed.us. Widespread destruction The loss of biodiversity in large areas of Amazon rainforest could result in the loss of many animal and plant species. Exbrayat stated that “our study suggests that the large-scale deforestation of the Amazon has been partly offset by continued regrowth, even despite sustained human activities.” This study was supported by the Natural Environment Research Council. Citation: Jean Francois Exbrayat, Mathew Williams. “Quantifying historical Amazonian forest deforestation’s net contribution to climate change.” Geophysical Research Letter. Publised 19 April, 2015. DOI: 10. 1002/2015GL063497.
