The Amazon rainforest often called the lungs of the Earth, is facing a hidden crisis that lingers long after the flames are gone. A new study by researchers from Columbia University’s Climate School published in Environmental Research Letters, reveals that parts of the Amazon scorched by fire can remain significantly hotter for decades threatening their recovery and weakening their ability to store carbon and withstand climate stress.
According to the study, burned areas of the forest remain, on average, 2.6°C warmer than untouched or selectively logged forests. Even 30 years after a fire the temperature decrease in these areas is just 1.2°C, leaving them persistently hotter than normal. The elevated heat levels stretch across the entire canopy, from 5 to 40 metres, disrupting critical ecological processes.
Burned Canopy, Broken Balance
The research found that fires cause lasting structural damage to all layers of the forest canopy, allowing more sunlight and heat to penetrate. In regions like southern and eastern Amazonia, where seasonal water stress is already a challenge, this intensifies the heat burden even further.
On the hottest days, as many as 87% of leaves in burned patches exceeded the temperature at which leaf respiration overtakes photosynthesis essentially, when trees start to lose more carbon than they store. In comparison, that figure stood at 72–74% in intact or logged forests.
Notably, the upper canopy in burned areas experienced a slight increase in temperature with height something absent in healthier forests. This suggests that damage to upper layers reduces evaporative cooling, worsening the heat-trapping effect.
These higher and more erratic temperatures are disrupting natural regeneration. Seed germination, sapling growth, and species composition are all impacted. “Regeneration is much more at risk it’s slower or not happening at all,” said Savannah Cooley, the study’s lead author and a NASA research scientist. This poses a serious obstacle to recovery efforts, especially in forests that were already degraded before the fire.
Unlike fire-resilient ecosystems such as pine forests or savannahs, the Amazon has no evolutionary defense against fire. Its flora evolved in a wet, fire-free environment, making most tree species highly vulnerable to even a single burn event.
Implications for Climate and Restoration
This research underscores a major blind spot in climate mitigation planning. Degraded forests especially fire-damaged ones are often assumed to recover their carbon absorption ability over time. But this study shows that their capacity to sequester carbon remains seriously compromised for decades.
The authors argue that such forests may need active restoration, such as replanting and soil enrichment, rather than just being left to recover naturally. “Burning has major ecological impacts over large timescales,” Cooley warned, “and strategies must reflect that reality.”
A Global Wake-up Call
As global temperatures rise and fires whether from deforestation, agriculture, or drought become more frequent, the Amazon’s role as a climate buffer is being weakened. Fire damage doesn’t just kill trees it alters the forest’s climate from within, locking in heat, disrupting regrowth, and turning once-vibrant ecosystems into long-term carbon sources rather than sinks.
The study urges policymakers, restoration planners, and climate strategists to rethink assumptions about forest recovery and prioritize fire prevention and active intervention to save the Amazon from becoming a shadow of its former self.