Tim Brodribb has been measuring all the different ways global warming kills trees for the past 20 years. With a microphone, he says, you can hear them take their last labored breaths. During blistering heat waves and droughts, air bubbles invade their delicate, watery veins, cracking them open with an audible pop. And special cameras can film the moment their drying leaves split open in a lightning bolt pattern, disrupting photosynthesis.
“We really need to be able to hear these poor trees scream. These are living things that are suffering. We need to listen to them,” said Brodribb, a plant physiologist at the University of Tasmania who led a recent study that helps identify exactly when, where and how trees succumb to heat and dryness.
The study, published April 17 in the journal Science, reviewed the last 10 years of research on tree mortality, concluding that forests are in big trouble if global warming continues at the present pace. Most trees alive today won’t be able to survive in the climate expected in 40 years, Brodribb said. The negative impacts of warming and drying are already outpacing the fertilization benefits of increased carbon dioxide.
Trees and forests can be compared with corals and reefs, he said. Both are slow-growing and long-lived systems that can’t easily move or adapt in a short time to rapid warming and both have relatively inflexible damage thresholds. For corals, a global tipping point was reached from 2014 to 2016. In record-warm oceans, reefs around the world bleached and died.
Source: Insideclimate News