Scientists rethink how much carbon forests can store; Mukund Palat Rao states, "Right now, most models assume that if you have photosynthesis, you have growth."

Scientists are rethinking the relationship between photosynthesis and carbon storage in forests. Research led by Mukund Palat Rao from Columbia University reveals that 36% of carbon absorption occurs after tree growth has ceased, challenging traditional models that equate photosynthesis with growth.¹

Rao stated, “Right now, most models assume that if you have photosynthesis, you have growth. We find that’s not the case.” This disconnect is particularly evident during periods of extreme weather, where 26% of annual carbon uptake happens post-growth cessation.

The study highlights that oak trees can continue photosynthesizing long after their annual growth stops, indicating that increased carbon intake does not necessarily lead to more carbon stored in wood. Rao emphasized the importance of understanding this relationship for predicting long-term carbon storage in forests, stating, “Understanding how photosynthesis and growth are linked is very important from the perspective of understanding how forests will store carbon over long time scales.” The findings suggest that under dry and hot conditions, growth activity halts quickly, while photosynthesis persists at a reduced rate, complicating the carbon storage narrative.²³

This research could reshape how scientists model forest carbon dynamics, especially in the context of climate change and its impact on forest ecosystems.