The Amazon rainforest is becoming less resilient – raising the risk of widespread dieback, new research shows.
The study found that resilience – the ability to recover from events such as droughts or fires – has declined consistently in more than three quarters of the rainforest since the early 2000s.
The research is part of the project “Tipping Points in the Earth System” funded by European Union’s Horizon 2020 programme, and received additional funding from the Leverhulme Trust and The Alan Turing Institute.
Experts believe the Amazon could soon reach a tipping point, crossing of which would trigger dieback and turn much of the forest to savannah, with major impacts on biodiversity, global carbon storage and climate change.
It is not clear when that critical point could be reached, but the study says the loss of resilience is "consistent" with an approaching tipping point.
The study used various data sources, including satellite data on Vegetation Optical Depth (VOD) – a measure of the total biomass of trees and other plants in a given area.
"The Amazon rainforest is a highly complex system, so it's very difficult to predict if and when a tipping point could be reached," said Dr Chris Boulton, of Exeter's Global Systems Institute.
"We now have satellite data on the Amazon that covers a sufficiently long timespan to observe changes in resilience. Our study looked in detail at month-to-month changes as the forest responded to fluctuating weather conditions.”
"The rainforest can look more or less the same, yet it can be losing resilience – making it slower to recover from a major event like a drought," explained Professor Tim Lenton, Director of Exeter’s Global Systems Institute.
Professor Lenton added: "This gives new compelling evidence to support efforts to reverse deforestation and degradation of the Amazon to give it back some resilience against ongoing climate change."
The research was carried out by the University of Exeter, the Potsdam Institute for Climate Impact Research (PIK) and Technical University of Munich.
The paper, entitled "Pronounced loss of Amazon rainforest resilience since the early 2000s.” is published in the journal Nature Climate Change.
