DATE: May 14, 2019
SNIP: It is well known that the burning of fossil fuels and deforestation both lead to the emission of carbon dioxide, raising temperatures worldwide. Less well understood is how removing tree cover is contributing to increased temperatures at a local level – until now.
In a new study published in the open-access journal PLOS ONE, scientists from Brazil’s Rio de Janeiro State University and the University of California, Santa Cruz (UCSC), have found that the temperature increase in the immediate vicinity of a deforested area could be as much as 1.45 degrees Celsius (2.6 degrees Fahrenheit) by 2050 in tropical areas such as Brazil’s Amazon basin or in the Cerrado, the nation’s savanna biome.
“Everyone is familiar with how hot it is in cities compared to a forest environment, and this is because the energy is absorbed and then generates infrared radiation that heats up the environment. The same happens if you deforest,” explained study co-author Barry Sinervo of the UCSC Department of Ecology and Evolutionary Biology in a Mongabay interview.
The paper explores how the albedo effect (whereby lighter-colored surfaces reflect heat, while darker ones absorb it), and the loss of evapotranspiration (whereby water goes back into the atmosphere from land, trees and plants) can both lead to warming on a local scale within deforested tropical areas. By contrast, loss of vegetative cover in sub-Arctic boreal forests has little impact on local temperatures.
“We show that the heating in those [tropical] deforested habitats can have an effect at a very local scale,” Sinervo said. “And that means, even if you have an intact forest, it is getting hotter because of the deforestation that’s occurring around it.”
Under BAU [Business As Usual], it is estimated that 606,000 square kilometers (234,000 square miles) of forest could be lost by 2050, leading to local temperature increases of up to 1.45 degrees Celsius (2.6 degrees Fahrenheit), with an average increase of 0.11 degrees Celsius (0.2 degrees Fahrenheit).