The Amazon Rainforest has had a pretty rough time of it over the years and it seems the next century isn’t looking too peachy either. Recent findings suggest that unless measures are taken to curb climate change, areas in the east of the rainforest will face extreme drought risk, far higher than previously thought, in the next hundred years.
Whilst previous climate models have contradicted one another as to whether the Amazon will become wetter or drier in coming years, a new study, published in Environmental Research Letters, favors the latter outcome. The researchers predict a reduction in rainfall comparable to those of the major droughts of 2005 and 2010, which caused widespread tree damage and mortality, and also devastated communities.
To achieve this conclusion, the team, led by Dr Jessica Baker of the University of Leeds' School of Earth and Environment examined the relationship between precipitation and evapotranspiration – the plant-mediated transfer of water from the soil to the atmosphere – in 38 known Amazon climate models. They found that only a third of these models correctly represented the interaction and were able to rule out the other, unrealistic, models, reducing uncertainty in rainfall predictions by half.
This allowed for much more accurate predictions of Amazon precipitation than ever before; severe drying is predicted in the eastern Amazon by 2100, while rainfall increases are expected in the west. Factors controlling evapotranspiration were also found to evolve over time, “reducing climate stability and leaving the region vulnerable to further change” write the authors.
"This new study sheds light on how the Amazon climate is likely to change under an extreme warming scenario,” Baker said in a statement. "Protecting and expanding existing forests – which absorb and store carbon – is of paramount importance to combatting climate change."
The Amazon basin plays a vital role in the world’s carbon and water cycles. If the drying occurs as forecasted in this study, the global implications could be huge. Thanks to deforestation, the Amazon already released more carbon dioxide than it absorbed between 2010 and 2019. And now this new data suggests that large amounts of greenhouse gas will be released into the atmosphere as a result of the anticipated drought, creating a vicious cycle of climate change. Not only this, but the risk of forest fires will be greater, and an even larger water stress will be placed on the trees – large areas of the rainforest may become unviable. Biodiversity, which has been maintained in some parts for 5,000 years, will also suffer.
It seems combatting climate change is absolutely necessary to protect the Amazon and remedy future climate change. As Baker says, this new research “should ring alarm bells for governments around the world that this vital global resource must not be taken for granted”.
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