A new study reveals that coast redwood trees are dialing down their photosynthesis during heatwaves, conserving water but starving themselves of crucial carbon. This could spell trouble for the towering giants and the creatures that call them home.

Tree physiologist Lily Klinek explains that redwood leaves can only cool down effectively if they have enough water. During heatwaves, the trees close their stomata, reducing water loss but also carbon intake, leading to a vicious cycle of carbon starvation.

The impact is not just about the trees themselves but the broader ecosystem. Redwoods store vast amounts of carbon and support diverse habitats. If they struggle, so too may the myriad creatures that depend on them. It's a sobering reminder of the interconnectedness of our planet's living systems.

This phenomenon, while observed in tropical trees, is the first detailed study on coast redwoods. The threat is compounded by the loss of coastal fogs, which provide vital hydration and a cooler microclimate. As oceans warm and air dries, these iconic trees face an uncertain future.