This study investigates the large-scale response of vegetation physiology to drought using remotely sensed data and machine learning. The researchers find that vegetation functional decreases are primarily driven by the downregulation of stomatal conductance and light use efficiency, particularly in water-limited regions. Discrepancies between functional and structural changes under severe drought are observed in wet regions. Model simulations support these findings, highlighting the importance of aridity, hydrometeorological conditions, and vegetation type in controlling physiological drought responses. Isolating and quantifying these responses improves understanding of ecosystem feedback in climate change.

Wantong Li, Javier Pacheco-Labrador, Mirco Migliavacca, Diego Miralles, Anne Hoek van Dijke, Markus Reichstein, Matthias Forkel, Weijie Zhang, Christian Frankenberg, Annu Panwar, Qian Zhang, Ulrich Weber, Pierre Gentine, Rene Orth