Burning, Even On Its Margins, Combines W. Black Carbon To Dry Amazon Rainforest
The burning of vegetation and the release of climate-warming gases into the atmosphere are conspiring to dry out the Amazon rainforest, according to a new study.
“We observed that in the last two decades, there has been a significant increase in dryness in the atmosphere as well as in the atmospheric demand for water above the rainforest,” Armineh Barkhordarian, an assistant researcher at NASA’s Jet Propulsion Laboratory (JPL) and the lead author of the study, said in a statement.
Fires in the Amazon captured the world’s attention in the late summer of 2019. Though a recent analysis demonstrated that most of the fires were burning on recently deforested land, not the forest itself, the release of “black carbon” into the atmosphere above the forest is still having a substantial impact. These fires, primarily set to clear the way for agriculture and pastures, feed a cycle in which droughts and fires will continue to be more likely.
Publishing their work Oct. 25 in the journal Scientific Reports, Barkhordarian and her colleagues used satellite-mounted instruments to come up with what’s known as the vapor pressure deficit, or VPD, across tropical South America. The VPD is the gap between the maximum amount of moisture the air can hold and how much moisture is actually there, and it’s been notching upward — meaning drier air in the Amazon — over the past few decades. The team’s analysis leaves little doubt that humans are behind this precipitous change. “In comparing this trend to data from models that estimate climate variability over thousands of years,” Barkhordarian said, “we determined that the change in atmospheric aridity is well beyond what would be expected from natural climate variability.”
EDIT
https://news.mongabay.com/2019/11/fires-and-greenhouse-gases-fuel-drying-of-the-amazon/
