Amazon Burned forests remain warm and stressed for decades, find a new study backed by NASA-Estate on the planet

The forests in the Brazilian Amazon damaged by the fire remain approximately 2.6 ° C (4.7 ° F) hotter than the intact or selectively registered neighboring supports, and the additional heat can remain for at least 30 years. The findings suggest that the fire alters tropical forests so that they slow down their recovery and can weaken their ability to tolerate climate stress and store carbon, a crucial role that these forests play in the mitigation of the global climate.

The study It was published today in the Magazine Environmental Research Letters.

“We are discovering that burning has important ecological impacts on large time scales and that regeneration is much more at risk: it is slower or not happening at all,” said the main author Savannah S. Cooley, a scientist of research scientist NASA AMES Research Center And a newly graduated from Columbia doctoral Ecology, Evolution and Environmental Biology (E3b) Program. (Cooley was co-co-co-elapsed by Duncan Menge and Ruth distrustDean professor and co -founder of the Columbia Climate School).

Unlike fire -adapted ecosystems, such as savannas or pine forests, Amazon’s tropical jungles evolved into wet conditions where natural fires were rare. As a result, many species of tropical trees have not developed features to tolerate or recover from fire damage.

In addition to being warmer on average, burned forests in the study area were more thermally unstable. Compared to selective or intact recorded forests, they experienced greater daily temperature fluctuations and were more likely to cross the physiological thresholds that affect the tree function. During the maximum heat of the dry season, almost 87% of the leaves exposed to sunlight in the burned forests lose more energy of the breathing that they gain from photosynthesis, compared to 72-74% in selectively recorded or intact supports.

Burned forests also had 10 times more likely to cross the threshold for lasting damage.

These temperature differences reflect fundamental changes in the forest structure left by the burned areas most vulnerable to heat. Fire thin the upper canopy, eliminate vegetation of medium and lower level and reduce the area of the leaf, decreasing the shadow and perspiration that a forest usually cools. Less leaves allow sunlight to exposed and air surfaces near the canopy. Burns also creates edges next to the clear earth, allowing the warmest air to move in. The forest retains this extra heat until its layers of vegetation reconstruct, a process that can take decades.

The study suggests that fire is the main driver of prolonged heat stress in degraded Amazonian forests. In areas where selective logging left the canopy mostly intact, temperatures were similar to those of non -disturbed forests. The contrast highlights fire prevention and low impact registration as key strategies to maintain the health of tropical forests.

Ideas from space

The study is based on satellite images of the municipality of Feliz Natal in the Arch of Deforestation of Brazil, a region in southeastern Amazonas where fire and logging have accelerated since the 1980s. The researchers made the first systematic thermal comparison of burned forests, selective registered and intact in the area using integrated satellite observations. They combined three years of NASA Earth’s Earth’s Temperature Data ECOSTRES INSTRUMENT with 3D canopy structure data Gedi Lidar missionAn analysis that resorted to more than 6,700 coincident observations collected during the Dry Amazon station.

Using a hierarchical model, the equipment integrated the temperature and data structure to track how often the sun -illuminated leaves exceeded the thresholds for the deceleration of photosynthesis or tissue damage. Factorization in the height and time of the canopy from the disturbance, rebuilt long -term thermal recovery through the forest layers. The result is a unique vision at the leaf level of how long heat stress persists after disturbance and how the forest structure influences thermal vulnerability over time.

Hidden heat reveals new risks of restoration and resilience

The results provide nuances to the understanding of how climate policy addresses the degradation of the tropical forest. Carbon and forest restoration strategies often treat degraded forests as a single category. However, the study reveals that the fire has more durable thermal impacts that are not detectable only by conventional optical satellite images. In optical satellite images, fire -damaged forests may seem to have returned, but many still experience high heat stress.

The distinction is important because tropical forests eliminate large amounts of carbon dioxide from the atmosphere every year and are a key component of global restoration and compensation programs. If fires damaged by fire remain thermally stressed for decades, carbon benefits of the passive regrowth can be exaggerated. The incorporation of physiological heat data can provide a more realistic evaluation of forest function in climatic strategies.

While the findings highlight the challenges, Cooley said that significant action is possible.

“Degraded tropical ecosystems, especially burned forests, are experiencing thermal stress,” he said. “But there is much we can do to minimize the damage to biodiversity and the species that are experiencing this stress, both in terms of forest management, helping to reduce fires in the Amazon and on the side of carbon mitigation, continuing to reduce aggressive and fast emissions, and the transition to a clean and sustainable energy economy.”

The co -authors of the study are Duncan NL Menge, University of Columbia; Michael Keller, Forest Service of the USDA and NASA Jet Propulsion Laboratory; Kerry Cawse-Nicholson, NASA Jet Propulsion Laboratory; Marcos Longo, Lawrence Berkeley National Laboratory; André P. Dias, Secretary of State of Meio Environment; Vinicius Silgueiro and Raquel Carvalho, Life Center Institute; Ovidiu Csillik, University of Wake Forest; Doug Anderson, Micah Gilbreath and Paul Duffy, Neptune and Company, Inc.; and Marcos Adami, National Institute of Espaciais investigations.