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--></style><title>A long look back at fire in the Sierra
Nevada</title></head><body>
<div><font face="Lucida Grande"
size="-1">====================================================</font></div
>
<div><font face="Lucida Grande" size="-1">"Large shifts in the
fire record corresponded with socio-ecological change, and not climate
change, and socio-ecological conditions amplified and buffered fire
response to climate," the researchers report in today's (Nov. 14)
issue of the<i> Proceedings of the National Academy of
Sciences</i>.</font></div>
<div><font face="Lucida Grande"
size="-1"
><<http://www.pnas.org/content/early/2016/11/08/1609775113.abst<span
></span>ract>></font></div>
<div><br></div>
<div>"<font face="Lucida Grande" size="-1">The Native American
mosaic of burned and unburned area prevented fires from continuously
spreading.</font>"</div>
<div><br></div>
<div><font face="Lucida Grande" size="-1">"Before the Native
American die off, fires burned 4.5 times more area than they do
today," said Taylor. "After the Native American depopulation
fires burned 8 times more area than they do today."</font></div>
<div><br></div>
<div><font face="Lucida Grande" size="-1">"We did eventually
develop an understanding of how climate patterns could be used to
develop long-lead forecasts," said Taylor. "But there has to
be a consideration of both people and climate to predict and plan for
future fire activity."</font></div>
<div><font face="Lucida Grande"
size="-1">========================</font></div>
<div><font face="Lucida Grande" size="-1"><br></font></div>
<div><font face="Lucida Grande" size="-1">Human actions influence fire
regimes in the Sierra Nevadas</font></div>
<div><font face="Lucida Grande" size="-1">PENN STATE PUBLIC
RELEASE: 14-NOV-2016</font></div>
<div><font face="Lucida Grande" size="-1"><br></font></div>
<div><font face="Lucida Grande" size="-1">While climate contributes
strongly to fire activity in the Sierra Nevada mountains of the
western U.S., human activity, starting well before European contact,
has also played an important part in the severity, frequency and sheer
numbers of forest fires occurring in the area, according to
researchers.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
"Initially, we did work to see if we could develop long-lead
forecasts for fire in the area -- six to 18 months in the future --
using climate patterns such as El Nino," said Alan H. Taylor,
professor of geography, Penn State. "This would be a significant
help because we could place resources in the west if forecasts
indicated it would be dry and the southeast would be wet. However, the
climate relationships with fire did not consistently
track."</font></div>
<div><font face="Lucida Grande" size="-1"><br>
Taylor, working with Valerie Trouet, associate professor of
dendrochronology, University of Arizona, merged a tree-ring-based
record of Sierra Nevada fire history with a 20th century record based
on annual area burned to create a record of fires spanning 415 years,
from 1600 to 2015. While year-to-year fire variability was influenced
by climate throughout that time, they found that large decadal-scale
shifts in the Sierra Nevada fire regime were related to changes in
human activity.</font></div>
<div><font face="Lucida Grande" size="-1">"Large shifts in the
fire record corresponded with socio-ecological change, and not climate
change, and socio-ecological conditions amplified and buffered fire
response to climate," the researchers report in today's (Nov. 14)
issue of the<i> Proceedings of the National Academy of
Sciences</i>.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
The researchers uncovered four time periods, each possessing their own
fire regime characteristics that, while impacted by climate, were also
heavily influenced by human land use patterns. The earliest fire
regime period, dating from 1600 to 1775, corresponded to the time
before Europeans came to the California area. During this time, Native
Americans used fire to improve the production of acorns, tubers,
shrubs and game such as deer. Their burn regime also controlled the
amount of fuel on the forest floor. Native Americans who used the
Sierra Nevada forests created a mosaic of small burned areas
interwoven with unburned forest.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
Early fires, because they were more frequent with less fuel build-up,
were "good" fires. They burned through the forest, consumed
understory fuels and left the majority of trees unharmed. The Native
American mosaic of burned and unburned area prevented fires from
continuously spreading.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
>From 1776 to 1865 the second fire regime, characterized by Spanish
colonialism and the depopulation of Native Americans in the area shows
more land burned. European settlers brought diseases against which
Native Americans had no immunity and the population suffered. The
Spanish built a string of missions in California beginning in 1769 and
relocated remaining Native Americans to the mission areas. In 1793,
there was a ban on burning to preserve forage, disrupting the
pre-colonial Native American burning practices. The incidence of fires
became more sensitive to drought and the fire regime changed, creating
a time when fires were largest and most closely coupled with
climate.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
"Before the Native American die off, fires burned 4.5 times more
area than they do today," said Taylor. "After the Native
American depopulation fires burned 8 times more area than they do
today."</font></div>
<div><font face="Lucida Grande" size="-1"><br>
The third fire period is from 1866 to 1903 and was initiated by the
California gold rush, when thousands of people poured into the area.
Settlement by large numbers of new immigrants began to break up the
forest fuel and the creation of large herds of animals, especially
sheep, removed large amounts of understory and changed the fire
regime.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
The fourth fire period began in 1904 and is linked to the federal
government's policy of fire suppression on government lands. The
reason pre-colonial and Spanish colonial fire levels were so much
higher than today is that the current fire regime is one of
suppressions with an extremely low incidence of fires compared to the
past. However, suppression over the last century has allowed fuel to
build up on the forest floor and opened the door for "bad"
fires that destroy the forest canopy and burn large areas of
land.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
"Fire was locked in with decadal temperature variation until
about 1860, after which time the relationship decays until the 1980s,
when fire tracks temperature again," said Taylor.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
The decay occurred because people changed the landscape through
grazing and then changed the forests by suppressing fire.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
Today's fires, according to Taylor, can be "bad" fires
because a century or more of fire suppression has created a vast store
of fuel to accumulate on the forest floor, allowing fires to burn long
enough and hot enough to kill the forest canopy. These fires are also
harder to fight.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
"It is important for people to understand that fires in the past
were not necessarily the same as they are today," said Taylor.
"They were mostly surface fires. Today we see more canopy-killing
fires."</font></div>
<div><font face="Lucida Grande" size="-1"><br>
Climate is still an important part of the regional fire regime.
Extremely dry times will increase fire prevalence and extremely wet
periods will decrease fires occurrence. But climate alone, in an
inhabited area, cannot predict the fire regime. The actions of people
must also be considered.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
"We did eventually develop an understanding of how climate
patterns could be used to develop long-lead forecasts," said
Taylor. "But there has to be a consideration of both people and
climate to predict and plan for future fire activity."<br>
###<br>
Also working on this project were Carl N. Skinner, geographer, Pacific
Southwest Research Station, U.S. Forest Service and Scott L. Stephens,
professor of environmental science, policy and management, University
of California, Berkeley.</font></div>
<div><font face="Lucida Grande" size="-1"><br>
The U.S. Forest Service supported this research.</font></div>
<div><br></div>
<x-sigsep><pre>--
</pre></x-sigsep>
<div><font face="Geneva" size="-1"
color="#000000"
>====================================================================<span
></span>====</font></div>
<div><font face="Arial" color="#000000">"Trump promised to
"cancel" the international climate change accord in his first 100
days of office. Seeing that the deal went into effect last week, he
will have to wait ... . But in the meantime, the United States
could severely handicap the deal by not following through on emissions
cuts and reneging on promised funds for global climate
adaptation.</font><font face="Geneva" size="-1"
color="#000000">"</font></div>
<div><font face="Geneva" size="-1" color="#000000"><br></font></div>
<div><font face="Geneva" size="-1"
color="#000000"
>http://grist.org/politics/trump-will-be-the-fossil-fuel-industrys-gr<span
></span>eatest-gift/</font></div>
<div><font face="Geneva" size="-1"
color="#000000"
>====================================================================<span
></span>====</font></div>
<div><font face="Geneva" size="-1" color="#000000">"Congress offers
change without change -- a green economy built on cheap coal and
petrol -- because that is what voters want. Is it too much to ask that
Mr Obama should tell voters the truth? I think he could do it. He has
everything it takes to be a strong president. He is choosing to be a
weak one."</font><br>
<font face="Geneva" size="-1" color="#000000"></font></div>
<div><font face="Geneva" size="-1" color="#000000">Clive Crook.
"Obama is choosing to be a weak president." Financial Times, June
28, 2009</font></div>
<div><font face="Geneva" size="-1"
color="#000000"
> =====================================================</font></div
>
<div><font face="Geneva" size="-1" color="#000000">"Everybody
knows the ship is sinking. Everybody knows the captain
lies."</font></div>
<div><font face="Geneva" size="-1" color="#000000"><br></font></div>
<div><font face="Geneva" size="-1" color="#000000">Leonard
Cohen</font></div>
<div><font face="Geneva" size="-1"
color="#FFFF00"><u><br></u></font></div>
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