Reconfiguration of Amazon's Connectivity in the Climate System

TL;DR

This paper analyzes how Amazon rainforest connectivity with the global climate system has changed over time, revealing increased variability and faster spread of perturbations, using advanced climate network analysis methods.

Contribution

It extends climate network analysis techniques to study Amazon connectivity evolution, providing new insights into regional-global climate interactions and methodological innovations.

Findings

Amazon shows decreased short-range and increased long-range connectivity.

Connectivity patterns have become more variable in the 21st century.

Perturbations spread faster from the Amazon in recent decades.

Abstract

With the recent increase in deforestation, forest fires, and regional temperatures, the concerns around the rapid and complete collapse of the Amazon rainforest ecosystem have heightened. The thresholds of deforestation and the temperature increase required for such a catastrophic event are still uncertain. However, our analysis presented here shows that signatures of changing Amazon are already apparent in historical climate data sets. Here, we extend the methods of climate network analysis and apply them to study the temporal evolution of the connectivity between the Amazon rainforest and the global climate system. We observe that the Amazon rainforest is losing short-range connectivity and gaining more long-range connections, indicating shifts in regional-scale processes. Using embeddings inspired by manifold learning, we show that Amazon connectivity patterns have become more variable in the twenty-first century. By investigating edge-based network metrics on similar regions to the Amazon we see the changing properties of the Amazon are significant in comparison. Furthermore, we simulate diffusion and random walks on these networks and observe a faster spread of perturbations from the Amazon in recent decades. Our methodology innovations can act as a template for examining the spatiotemporal patterns of regional climate change and its impact on global climate using the toolbox of climate network analysis.