Deforestation Could Push Amazonia Close to a Tipping Point Under Future Climate Change

Abstract

Abstract We use a coupled land‐surface‐atmosphere single‐column model to examine the effects of deforestation and changed advective moisture flux (AMF) on the Amazonian system. We find that from current conditions, a reduction to 35% forest cover, or a ∼10% decrease in AMF (∼6% less precipitation), causes the system to transition from a wet climate with rainforest to a drier climate with savanna‐like vegetation. The system responds highly non‐linearly to the combined influences of the AMF and deforestation. Small changes in either forest cover or moisture advection are capable of causing the system to flip abruptly between stable forest, savanna, or shrubland states. Model behavior is strongly influenced by the feedback between the land surface and the atmosphere, with natural vegetation changes playing a major role. Our results suggest that continued deforestation is likely to trigger a transition to a savanna‐like state across Amazonia within this century under current climate projections. Plain Language Summary We used a computer model to study how deforestation and changes in rainfall affect the Amazon rainforest. The interaction between the land and the atmosphere plays a crucial role. Our findings show that the system's response is highly dynamic. A reduction of over 65% in forest cover or a 10% decrease in moisture flow from the current rainforest conditions could shift the climate from a wet rainforest to a drier savanna‐like environment. Importantly, we find that the combined impact of deforestation and reduced precipitation weakens the forest's resilience. Our projections suggest that if current trends continue, the Amazon system could reach a critical tipping point within this century. Deforestation and decreased rainfall may transform the Amazon from a lush rainforest to a more arid, savanna‐like landscape. Our findings highlight the urgent need to limit deforestation and mitigate climate change in order to ensure the long‐term health and stability of the Amazon rainforest. Key Points The Amazon basin faces a climate shift: 65% deforestation or 10% less moisture triggers a change from a rainforest to a savanna‐like state Deforestation coupled with reduced moisture flux weakens the Amazon basin's resilience, potentially pushing it toward irreversible change Urgent action is needed since deforestation and reduced moisture influx could push the Amazon basin to a tipping point within this century