The Amazon rainforests are turning from sink to source of carbon dioxide, scientists have stated on Wednesday. According to the study published in the journal Nature, Amazon rainforests are emitting more carbon dioxide than they can absorb, as these emissions represent a billion tonnes of carbon dioxide annually. These emissions are mostly caused by forest fires, some of which are intentionally aimed at clearing land for livestock and soy production.
How are Amazon rainforests are changing?
Over the last decades, to measure the CO2 levels up to 4500 meters above the jungle small planes were used by researchers. It reveals how the Amazon forests have changed. But the earlier research implying that Amazon was becoming a source of CO2 was based on satellite data. So, this may be impeded by cloud cover or subsurface tree surveys, which can only cover a fraction of a large area, reports The Guardian.
Although in the absence of fire, due to warmer temperatures, and droughts, Amazon’s southeast has become a source of CO2 instead of sink. According to scientists, it is quite disturbing that the parts of the Amazon emitting carbon dioxide even without fires, which is especially worrisome and a matter of concern.
Scientists believed it is probably due to annual deforestation and fires, making nearby forests more vulnerable the next year. Trees produce much of the rain in the area, resulting in fewer trees leading to more severe droughts and heatwaves. So, there will be more tree fires and fatalities.
The Amazon rainforest is the world’s largest tropical forest so it plays a major role in absorbing fossil-fuel emissions. Since 1960 tree and plant farming has accounted for about one-quarter of all fossil fuels emissions. But over the years as the Amazon rainforest is losing its power to absorb CO2 which gives us a serious warning to reduce fossil-fuel emissions as soon as possible otherwise it results in the biggest disaster ever, said scientists.
Brazillian Amazon emitting more CO2!
According to the study led by Luciana Gatti at the National Institute for Space and Research in Brazil said, “The first terrible news is that burning produces about three times the amount of CO2 that the forests absorb. The second piece of bad news is that places with 30% or more deforestation have 10 times more carbon emissions than the places with less than 20% deforestation.”
Fewer trees meant less rain and warmer temperature, which made the season even drier for the other forests. “We have a truly negative loop that makes the forest more susceptible to uncontrolled fires,” she added.
According to the research published in the journal Nature, between 2010 and 2018, 600 fire-induced vertice profiles of CO2 and carbon monoxide were collected from four sites in Brazil’s Amazon. As a consequence, fires have been found to create 1.5 billion tonnes of CO2 annually, while forest growth has eliminated 0.5 billion tonnes. One billion tonnes of CO2 is equivalent to the world’s fifth-largest carbon emitter country Japan.
“There is now a shred of strong evidence that this is happening. Southeast Amazon becoming a source from the sink is the story that tells that it is one more severe warning that the climate changes are accelerating,” said Prof Scott Denning, an atmospheric scientist at Colorado State University.
“In southeast forests no longer grows as rapidly as they die. The fact that the world’s most productive carbon absorber is turning from a sink to a source. This means we need to get rid of fossil fuels further than we expected.”
Brazilian Amazon has released close to 20% more carbon dioxide into the atmosphere in the last decade than it has absorbed, said a satellite study, published in April, done using different methodology. Research on 300,000 trees in 30 years, published in 2020, has shown that rainforests absorb less CO2 than they used to.
“Imagine if we ban fires in the Amazon, then it will be a carbon sink,” said Gatti. “But we are doing the opposite, we are speeding up climate change. What’s worse is that we don’t use science for decision-making.”
She added “According to people, if we convert more land to agriculture, it will lead to more productivity. However, we lose productivity due to the negative impact of rain.”