By 2050, deforestation could lead to a 15% drop in rainfall in tropical regions including the South American Amazon, Southeast Asia and Central Africa, the study published in the journal Nature Climate Change said.
Much of the logging taking place is to clear land for agriculture. This can cause a vicious cycle, increasing global warming, lowering food production on farms which in turn leads to growers cutting down more trees for farmland, experts say.
“When you deforest the tropics, those regions will experience significant warming and the biggest drying,” said Deborah Lawrence, a University of Virginia professor and the study’s lead author.
Removing trees and planting crops releases carbon dioxide into the atmosphere, contributing to global warming. At the same time, deforested areas are also less able to retain moisture, immediately altering local weather patterns.
The study said if current deforestation rates persist in South America’s Amazon rainforest, the region’s soy production could fall by 25% by 2050. Logging in the Democratic Republic of Congo or Thailand could also have impacts in other parts of the world, leading to more rainfall in UK and Hawaii and less rainfall in southern France and the US Midwest region, the study said.
Globally, levels of deforestation are increasing slowly, Lawrence said.
Brazil has brought rates down in a “wonderful success story”, she said, while the situation in Indonesia’s tropical forests has worsened. Complete tropical deforestation could lead to a 0.7 degree rise in world temperatures, on top of the impact from greenhouse gases, doubling global warming since 1850.
“Tropical forests are often talked about as the ‘lungs of the earth’, but they’re more like the sweat glands,” said Lawrence.
“They give off a lot of moisture, which helps keep the planet cool. That crucial function is lost — and even reversed — when forests are destroyed,” she added.
Meanwhile, another recent report found that mines, palm oil plantations, large farms and mining projects are contributing to an alarming pace of forest destruction, hampering efforts to curb global warming.
Satellite imagery indicates that more than 30,000 hectares of forest are lost daily, said the Securing Forests, Securing Rights report, unveiled recently in Peru by a coalition of rights groups during international climate change talks.
Forests play a key role in removing carbon dioxide from the atmosphere; chopping them down worsens global warming. Forests cover 30% of the planet’s surface and are home to c.350 million indigenous people — whose cultures and livelihoods are dependent upon them.