2018-11-28 15:38:46 UTC
(Clear warning from back in January, if the forest management
is not changed, there will be horrible fires.
"the billions of dollars that the state spends aggressively fighting
wildfires and restrictions on logging have allowed forests to
accumulate an overload of vegetation.")
California Today: 100 Million Dead Trees Prompt Fears of Giant Wildfires
Patches of dead and dying trees near Cressman, Calif., in 2016.
Scott Smith/Associated Press
Patches of dead and dying trees near Cressman, Calif., in
2016.CreditCreditScott Smith/Associated Press
By Thomas Fuller
Jan. 19, 2018
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The more than 100 million trees that died in California after being
weakened by drought and insect infestations have transformed large
swaths of the Sierra Nevada into browned-out tree cemeteries. In some
areas more than 90 percent of trees are dead.
This week a group of scientists warned in the journal BioScience that
the dead trees could produce wildfires on a scale and of an intensity
that California has never seen.
Coming in the aftermath of the deadly and destructive fires last year
both in wine country and Southern California, the warning is sobering
because the scientists say they cannot even calculate the damage the
dead-tree fires might cause; it exceeds what their current fire behavior
modeling can simulate.
“It’s something that is going to be much more severe,” said Scott
Stephens, a professor of fire science at Berkeley and the lead author of
the study. “You could have higher amounts of embers coming into home
areas, starting more fires.”
The authors of the study say the fire risk will ratchet up in the coming
years, as the dead trees fall to the forest floor and form a tangled
pile of timber resembling something like a giant bonfire.
Why do the researcher say we’ve never seen this before in California?
Mark A. Finney, an expert in fire behavior for the U.S. Forest Service
and an author of the study, says California forests are much more
vulnerable now because, paradoxically, they have been better protected.
In their natural state, forests were regularly thinned by fire but the
billions of dollars that the state spends aggressively fighting
wildfires and restrictions on logging have allowed forests to accumulate
an overload of vegetation.
“We had forests that were very resilient to weather variations and
insect disturbances in the past — maintained by frequent fire on the
order of every year, or every few years at the most,” Mr. Finney said.
By putting out fires, “we’ve changed completely the fire component of
these ecosystems,” he said.
How might the dead-tree forests affect California? One of the most
striking concerns is the damage the fires might do to watersheds.
Intense, hot-burning fires could disrupt forests’ ability to channel
water into the Sierra reservoirs that provide cities like San Francisco
with drinking water. That’s a scenario that could nudge the state into
rethinking its forest management.