Amazon deforestation reduces rainfall in South America

Experts have been talking for decades about the cause and effect effect between amazon logging and the reduction in rainy periods in bit rate and frequency. When miners, loggers and ranchers cleared the rainforest at a record pace, scientists were already warning of the consequences. However, researchers are still learning about the effects that human actions in forests have on the local and global climate balance.

British scientists have provided what they called “compelling evidence” around these actions for the first time. They were able to demonstrate link between deforestation and reduced rainfall throughout the tropics. “Local people living near deforested areas often report warmer weather And dry once the forests have been cleared. But until now, this effect had not been observed in observations of rain,” explained the co-author of the study and supervising professor of the project. Dominick Spracklen belonging to the School of Earth and the Environment of the University of Leeds, UK—. Our article shows the crucial importance of tropical forests in maintaining rainfall.”

The study, just published in Nature, made this crucial link by examining satellite data deforestation and rainfall in three key tropical forest regions: the Amazonhe congo and the South East Asia. All these regions had experienced significant deforestation between 2003 and 2017, the period observed by scientists.

The researchers analyzed the record rain both in deforested areas and where the forest has remained uncut. In their analysis, they found that deforested areas were drier, even in the dry season, when every drop of rain counts. During the rainy season, rainfall dropped by as much as 0.6 millimeters per month for every percentage point of land clearing.

The study authors also looked at how far the impacts of deforestation would go, on a scale of 25 to 40,000 square kilometres. In this analysis, they found that the effects increased with more land included, with no noticeable effects within 10 square miles (16 kilometers) of deforestation, but with a reduction in monthly rainfall of 0.25 millimeters per percentage point of cleared forest within a radius of 25,000 square kilometres.

Although the study does not prove that deforestation is the cause of the decrease in rainfall, it does provide evidence of a long held assumption that the loss of forests reduces rainfall because it means there is less evapotranspiration, the word that describes what happens when water from leaves rises into the atmosphere. If true, it could have serious consequences both for rainforests and for the people and animals that depend on them.

“Tropical forests play a vital role in the hydrological cycle by helping to maintain local and regional rainfall patterns,” said the study’s lead author and PhD researcher at University of Leeds, Callum Smith—. Reduced rainfall caused by tropical deforestation will affect people living nearby due to increased water scarcity and declining crop yields.

The conclusions of this study are also not good for the forests themselves. “Loss of rainfall can trigger other feedback loops of deforestation, such as a increased risk of forest fires, as well as hindering the ability of forests to store carbon and harm their biodiversity,” Smith added. The team also looked at the future potential of the Congolese rainforest and found that if current rates of deforestation persist until 2100, rainfall in the region could decrease by 8-10%.

However, there is a silver lining: evidence that deforestation leads to local rainfall loss is also an important short-term argument for forest conservation. For every percentage point of reduced rainfall, crop yields can drop by 0.5%. Given that agriculture is responsible for nearly 90% of global deforestation, these findings may raise questions among farmers about cutting down trees.

“Demonstrating the local benefit of keeping rainforests standing for people who live nearby has important policy implications,” Smith said. I hope our work will provide a strong incentive to policy makers and decision makers in tropical countries conserve rainforests to help maintain a cooler, wetter local climatewith benefits for agriculture and local populations,” he concluded.

JCA Baker, another member of the team from the University of Leeds, also participated in this research.

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