With about 17 per cent or more of the Amazon Rain forest lost, the forest is going to lose a major chunk of its trees with less rain in the region. Already drought has taken a toll on the rain forest and the coming years could be crucial if rains fail, a new study said.
The study said that the parts most at risk of turning into savannah are located on the forest’s southern fringes, where continuous clearing for pasture or soy has already been weakening the forest’s resilience for years.
AMAZON; LOSING RAIN AND EFFECT
As the rainforest in South America loses its rain, moisture supply also loses as climate change sends more frequent and more severe drought spells to the Amazon Basin. “That lack of rain threatens the forest, because it breathes water: Once rained down, the soil takes it up as much as the plants, and both release a great amount back through evaporation and transpiration. In this atmospheric moisture recycling, the forest creates much of its own weather, generating up to half of the rainfall over the Amazon Basin. And while it is highly efficient, at the end of the day the moisture recycling system relies on how much water is initially put into the system,” the researchers noted.
The researchers said that though a dry spell affects only one specific region of the forest, its harm stretches beyond that region by a factor of one to three. With the lack of rain strongly decreasing the water recycling volume, neighbouring regions also witness less rain. This leads to increased threat in more parts.
On the findings, Wunderling said that more intensive droughts put parts of the Amazon rainforest at risk of drying off and dying. He further explained that less forest cover leads to less water in the system.
AMAZON; DRY YEARS
The world has already seen extraordinarily dry years if 2005 and 2010.The scientists belive that this is going to become the new normal from 2050 onwards, with centennial droughts occurring in up to nine out of ten years by 2060. “These recurrent droughts are already producing quantifiable changes to the Amazon’s moisture network,” explains Henrique Barbosa, co-senior author on the study and assistant professor of physics at University of Maryland, Baltimore County. “We use these observations to understand and model the consequences of a future climate that resembles a permanent drought state.”
With respect to drought and Amazon, co-author of the study Boris Sakschewski said that droughts have different effects on forest systems here. “In the Amazon, trees and forest systems are differently adapted to water availability, as some regions commonly exhibit a distinct dry season while others have rain all year round. We specifically acknowledge these local adaptations as they can be a blessing or a curse under climate change,” said Henrique Barbos.
AMAZON; MORE TO DO
Expressing hope that not all is lost, Co-senior author of the study Ricarda Winkelmann said that this was because a good part of the forest is still in relatively stable conditions. “The network effects of dry spells are likely limited to certain areas in the forest’s southeast and southwest—which happen to be those areas where the forest has been suffering from the human hand already, in clearing forest for pasture or soy,” the researcher said.
“There is still a lot we can do to try and stabilize the Amazon, as preserving it and its ecological services is of utmost importance for local, regional and global climate stability,” Winkelmann says. “And we know how we can do that: by protecting the rainforest from logging, and by rapidly reducing greenhouse gas emissions to limit further global warming.