- Researchers at the University of Leeds found that if deforestation rates return to pre-2004 levels, average annual rainfall in the Amazon would decrease some eight percent by 2050.
- Such a significant drop in rainfall could impact ecosystems and wildlife throughout the Amazon Basin.
- Satellite data show tree cover loss in the Amazon Basin has largely trended downward since a surge in 2002, though 2014 numbers indicate deforestation may be on the rise.
Deforestation in the Brazilian Amazon took off in the 1970s, peaked in 2004 and dropped as much as 70 percent over the following decade.
But deforestation has risen in other Amazonian countries, and there are signs that deforestation rates are rising once again in Brazil, as well. A variety of research has shown the drastic impacts resurgent deforestation rates and climate change could have on the future of the Amazon.
Now, a new study published in Geophysical Research Letters, a journal of the American Geophysical Union, shows that if deforestation rates in Brazil, home to nearly two-thirds of the Amazon rainforest, return to pre-2004 levels, the amount of rain the entire Amazon Basin receives in drought years could essentially become the new normal.
“Maintaining low deforestation rates in the Amazon is essential to ensure survival of the Amazon forest,” Dominick Spracklen, an atmospheric scientist at the University of Leeds School of Earth and Environment in the UK and lead author of the report, said in a statement.
Spracklen and a team of researchers analyzed the results of 96 existing climate models and found a consensus that, if deforestation rates return to pre-2004 levels, average annual rainfall in the Amazon would decrease some eight percent by 2050, a larger decline than natural variability could possibly account for.
“We found a very consistent picture that deforestation is going to drive a reduction in rainfall, and that was consistent virtually across all models and all studies that we analyzed,” said Luis Garcia-Carreras, a research fellow at the University of Leeds Institute for Climate and Atmospheric Science and a co-author of the report. “And we found a picture that increasing deforestation drove larger reductions in rainfall.”
Such a significant drop in rainfall could impact ecosystems and wildlife throughout the Amazon Basin, according to the researchers. Brazil’s economy would also take a hit, they said, because less rainfall would have an obvious effect on agriculture, a $15-billion-a-year industry in the country, and hydropower, responsible for 65 percent of Brazil’s electricity.
It’s not clear what, if anything, Brazil plans to do to ensure deforestation rates don’t continue to climb. The country’s climate plan, submitted to the UN ahead of crucial climate negotiations to take place in Paris in just a few weeks, has been praised for setting an economy-wide emissions reduction target — but the plan does not include a goal of ending all deforestation in order to meet that target.
With global demand for commodities like beef and soy rising, it’s likely Brazil and other Amazonian countries will continue clearing forest, the study’s authors said. It’s even possible Brazil will relax its forest protection laws to meet the demand.
“I think one of the big environmental success stories of the past decade has been the reduction in deforestation in the Amazon, within Brazil,” Spracklen said. “But I think at the moment we’re at a kind of cusp, where there’s continued pressure within Brazil to relax some of the forest laws.”
- Hammer, Dan, Robin Kraft, and David Wheeler. 2013. “FORMA Alerts.” World Resources Institute and Center for Global Development. Accessed through Global Forest Watch on 11/16/15. www.globalforestwatch.org
- Hansen, M. C., P. V. Potapov, R. Moore, M. Hancher, S. A. Turubanova, A. Tyukavina, D. Thau, S. V. Stehman, S. J. Goetz, T. R. Loveland, A. Kommareddy, A. Egorov, L. Chini, C. O. Justice, and J. R. G. Townshend. 2013. “Tree Cover.” University of Maryland, Google, USGS, and NASA. Accessed through Global Forest Watch on 11/16/15. www.globalforestwatch.org
- Spracklen, D. V., & Garcia‐Carreras, L. (2015). The impact of Amazonian deforestation on Amazon basin rainfall. Geophysical Research Letters.