Code to support 'Canopy rejuvenation mitigates Amazon photosynthetic vulnerability to rising atmospheric dryness'

This repository contains the code and example data used to perform the analyses described in the following paper: 'Canopy rejuvenation mitigates Amazon photosynthetic vulnerability to rising atmospheric dryness' Rising atmospheric vapor pressure deficit (VPD) can constraint leaf-level photosynthesis by reducing stomatal aperture, yet can trigger canopy-level effects by stimulating plants to produce younger, more photosynthetically efficient leaves in Amazon rainforest. Here, we examine the opposing effects between leaf-level stomatal constraint and canopy-level rejuvenation using a satellite-based model. We show that incorporating canopy rejuvenation markedly improves the simulation of spatiotemporal variability in vegetation productivity, revealing that most of the Amazon rainforest exhibit a positive response of vegetation productivity to rising VPD. Canopy rejuvenation largely delayed the VPD threshold at which vegetation productivity becomes constrained. These results indicate that canopy rejuvenation makes Amazon rainforest productivity less vulnerable to rising atmospheric dryness than previously thought.