Climate change is moving too fast for these trees to keep up One in five Sierra Nevada conifers are no longer compatible with the environmental conditions around them, raising questions about how to manage the land. Researchers say it may get worse.

Climate is changing too quickly for the Sierra Nevada's 'zombie forests'

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Climate change is happening too quickly for some of the trees in California's Sierra Nevada mountains. New research shows that 1 in 5 conifers likely won't survive the climate conditions that they now live in. NPR's Joe Hernandez reports on the fate of these so-called zombie forests.

JOE HERNANDEZ, BYLINE: Even if you've never been to the Sierra Nevadas, you can probably picture the striking terrain.

AVERY HILL: Ponderosa pines, Jeffrey Pines, there are some Douglas firs in there as well - and these typically large, tall trees dominate these forests in the landscape.

HERNANDEZ: That's Avery Hill, who studied these trees as a graduate student at Stanford University. Hill and other researchers compared vegetation data from the 1930s to the present, and they found that 20% of the conifers in the California Sierra Nevadas are now a mismatch for the climate they live in. That means it's only a matter of time before these trees die out and get replaced with other types of plants.

HILL: They're kind of, you know, cheating death in a way. We think of them as the standing dead.

HERNANDEZ: That's why Hill and others have started calling these areas zombie forests. And the reason these conifers are in such danger is because the climate has changed a lot. Temperatures are warming, and there's less rainfall in these areas, which are also seeing an increase in wildfires and human activities like logging.

HILL: So altogether, these drivers are shaping kind of the forest of the future.

HERNANDEZ: The researchers made maps showing exactly where these Sierra Nevada zombie forests are, and Hill hopes that'll help put climate change into perspective for viewers.

HILL: It's not backwards-looking like I think a lot of the kind of ecosystem change conversations are. It's forward-looking and saying, OK, well, now what (laughter)?

HERNANDEZ: Having the knowledge of what climate change will do ahead of time gives people a choice, Hill says - try to resist or contain these changes or accept that they're going to happen.

Joe Hernandez, NPR News.

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