Climate crisis reaching tipping point where plants will no longer be able to photosynthesise, study warns

Sign up to the Independent Climate email for the latest advice on saving the planet Get our free Climate email Get our free Climate email SIGN UP I would like to be emailed about offers, events and updates from The Independent. The study reveals that an estimated 0.01 per cent of leaves in the upper canopies of tropical forests are currently experiencing temperatures that surpass the critical threshold for photosynthesis to function properly. “By looking at how leaf temperatures vary within and across forest canopies, this study offers novel new insights that this threshold is closer than we thought, but also that it is entirely within our collective means to navigate away from this dangerous threshold.” The study, led by Christopher Doughty and a team of researchers, utilised high-resolution measurements of land surface temperatures across various tropical forest regions, including Brazil, Puerto Rico, and Australia. Tropical forests are also key climate regulators of regional and global climate and any stress on them adds to the effects of climate change.” While the study confirms that the majority of tropical forest canopy temperatures peak at an average of 34C, it also highlights that a small fraction of observed areas exceed the concerning 40C mark. The study's models suggest that if global warming surpasses 3.9C—an extreme scenario—large-scale leaf death and loss within tropical forests could become a reality.