PNNL

A decade ago, little was known about the factors that contribute to plant death in the wild or how to predict vegetation death. Now, we have a much better idea, thanks to landmark research by Nate McDowell and his colleagues. By modeling tree mortality and survival in a warming world, McDowell has revealed important trends relating to biodiversity and carbon storage.

McDowell embarked on his research after receiving an Early Career Award from the Department of Energy to study how trees survive and die during drought. Funding from the award enabled McDowell to develop a model of vegetation mortality and validate it with independent field data. This work led to a study published in Nature Climate Change in 2016 predicting that few conifers would remain in the U.S. Southwest by 2050.

McDowell led a 2020 study of global forest dynamics, concluding that forests tend to be filled with younger, shorter trees in response to increasingly frequent stressors such as wildfires, drought, and wind damage.

“Over the last hundred years, we’ve lost a lot of old forests,” McDowell said. ”And they’ve been replaced in part by non-forests and in part by young forests. This has consequences for biodiversity, climate mitigation, and forestry.”

McDowell and colleagues have also examined how increased seawater exposure affects coastal forests.

"We still do not know where, how fast, and how much trees will die across much of the Earth," McDowell said in late 2020. His research continues to provide insight into these important questions. 

More Information

PNNL Staff Biography

“Can a new way to measure tropical rainforest vulnerability help save them?” July 23, 2021, National Geographic.