People, Environment

Amazon Deforestation Could Reduce Rainfall

Amazon Deforestation Could Reduce RainfallAmazon Deforestation Could Reduce Rainfall

Continued deforestation of the Amazon rainforest could diminish the amount of rain that falls in the Amazon River basin, a new study says. These declines in rainfall could potentially alter the region’s climate, disrupting rainforest ecosystems and impacting local economies, according to the study’s authors.

Deforestation of the Brazilian Amazon started on a large scale in the 1970s and peaked in 2004 before government restrictions curbed land clearing practices there. But deforestation has increased in other Amazonian countries in recent years, and Brazil is now facing pressure to convert more forest to pasture and crop land, according to the study’s authors, science new website reported.

New research predicts that by the middle of the century annual rainfall in the Amazon could be less than the yearly amount of rain the region receives during drought years if deforestation rates revert back to pre-2004 levels.

Essentially, drought years could become the norm for the Amazon by 2050 if deforestation rates rebound, said Dominick Spracklen, an atmospheric scientist at the University of Leeds School of Earth and Environment, United Kingdom, and lead author of the new study published today in Geophysical Research Letters, a journal of the American Geophysical Union.

This significant drop in rainfall could affect ecosystems and wildlife throughout the entire Amazon basin, which covers roughly 40% of South America, Spracklen said. The Amazon rainforest plays an important role in the global carbon cycle, so changes to Amazonian climate could affect global climate and weather, according to the study’s authors.

 Tricky Results

“Maintaining low deforestation rates in the Amazon is essential to ensure survival of the Amazon forest,” said Spracklen in a press release.

Destroying trees creates a water problem because trees are an important factor in regulating the exchange of water, energy and gases between the Earth’s surface and the atmosphere. Cutting down forests can alter local temperature, humidity and rainfall, though the results are tricky to forecast. To do so, the study’s authors did a meta-analysis of 96 different models.

The Amazon already is showing signs of water distress, with a 2014 study reporting that precipitation has decreased 25% since 2000 over a wide swath of the southeastern Amazon, and that vegetation in that area has suffered from the drying out.

South America will not be the only place that could suffer from the Amazon’s destruction, according to the study. The rainforest plays a crucial role in the entire planet’s carbon cycle, so there could be impacts upon global climate and weather as well.