Forests worldwide are vulnerable to growing risks of drought and heat-induced tree mortality because of a steadily warming Earth — that's according to a study that a University of Arizona natural resources professor contributed to.
Scientists at the U.S. Geological Survey and Los Alamos National Laboratory along with the UA’s Dave Breshears looked at more than 400 research studies on forest mortality. They wanted to answer the question: Are forests becoming more vulnerable to projected climate change?
"As scientists, we are underestimating how much of this is going to happen in the future. We’re in for a lot more tree mortality in the future," said Breshears.
Breshears said trees play a key filtering role in the ecosystem, especially in light of climate change.
"The problem with warming is having too much carbon in the atmosphere, so trees are also a source of holding carbon and sort of keeping the warming in check or minimizing how much carbon is going into the atmosphere," Breshears said.
He said climate change is creating droughts with higher temperatures that stress forests.
"So at some point during these hot droughts or during heat waves we’re pushing trees over the edge," said Breshears.
Breshears said he and his colleagues hope their work will be used by scientists and policy makers to figure out how to reduce global warming.