May 1, 2018 – A study by Oak Ridge National Laboratory detailed the response and recovery of certain tree species after short-term, extreme weather events such as heat waves. Scientists exposed sets of four different saplings to dramatic temperature swings that peaked above 120 F, or around 50 C, in a climate-controlled test chamber. Sensors attached to each tree and located throughout the chamber tracked telltale signs of heat and drought stress such as fluxes in carbon uptake and shifts in water demand. “By monitoring specific trait behavior, we characterized each tree’s reaction to being kicked into survival mode for brief periods of time,” said ORNL’s Anirban Guha. “We found that during simulated heat waves, the entire plant mechanism was impacted, which affects its year-long survival.” The ORNL-led team’s findings, which were published in Environmental Research Letters, will improve predictive Earth system models.