The
embers of last year’s wildfires are coming back with a vengeance
BETHEL
– Hidden underground all winter, an unusual number of holdover
fires that smouldered for months in Alaska’s deep duff already have
reignited this fire season, state forestry officials said Wednesday.
2
June, 2016
Last
year was the second-largest fire season on record in Alaska and 2015
“is still smoking,” officials said. One holdover on Sunday
sparked the 8,130-acre Medfra fire now burning in remote Southwest
Alaska.
Already
16 holdovers have been spotted, most of them on the Kenai Peninsula
or Kodiak Island. Holdover fires are ones that firefighters
thought were out, but come back to life as conditions dry out and
temperatures rise.
Hot
spots
“Most
of them start out as just little hot spots,” said Tim Mowry, the
state Division of Forestry public information officer. “The term
fire is sort of a misnomer. They are not really fires. They are
usually a little bit of smoke coming out of a burned area.”
The
count of 16 that have signaled their presence as of Wednesday appears
to be extraordinarily high. Some years there are none; some years
just a few. There aren’t records on holdovers, though. Mowry said
officials may start tracking them year to year.
It
also could be the holdovers are more exposed than usual this year, a
state fire behavior expert said.
Mushroom
lovers drawn to last year’s wildfire burns as prime picking grounds
spotted many of the Kenai smoke-ups, Mowry said.
‘Safety
hazard’
Fire
officials warn people to be cautious in burned areas and to call in
any smoke rising up from the blackened ground.
“It
is definitely a safety hazard,” Mowry said.
Alaska
is prone to wildfires, and the threat may be worsening. Three of the
top five fire seasons on record for Alaska have happened in the last
12 years. Fires are burning hotter and the fire season is starting
earlier and lasting longer.
Holdovers
also are common here, just not so many as this year, because of the
deep duff layer of composting moss, twigs, leaves and spruce needles
that blankets the forest floor or the rotting organic underlayer of
the tundra.
“It’s
the nature of Alaska and the thick layer of duff that we are talking
about,” Mowry said. “It shows you Alaska wants to burn.”
Hard
to fight
Once
a fire is established, it is very hard to completely douse, said
Robert Ziel, the forestry division’s fire behavior analyst.
Fires
burrow down and the duff above them absorbs the moisture.
“It’s
almost like an umbrella over that fire that keeps it insulated and
dry,” Mowry said.
Last
summer, more than 5.1 million acres burned, the second largest
expanse on record, according to the state. That big fire year
combined with low snow last winter and a warm dry spring all may have
combined to allow more holdovers.
Fire
managers send in crews to try and put down holdovers at the perimeter
of an already burned area but aren’t as worried about those
surrounded by charred land.
“Anything
that has the capability to reach out and grab unburned fuel is a
concern,” Mowry said.
Medfra
fire keeps growing
In
Southwest Alaska, officials are attributing the big Medfra fire that
started Sunday 50 miles northwest of McGrath to a holdover. It was
called in as a smoke report in an old burn area, then quickly spread
to fresh fuel. A helicopter from McGrath arrived to dump buckets of
water on it within an hour, but by then it had spread over an acre.
Smokejumpers stationed in McGrath attacked but it kept growing.
Tuesday
night, the Medfra fire merged with the smaller Berry Creek fire,
combining for an estimated 8,130 acres burned or burning. The two are
among three Southwest Alaska holdovers from the Soda Creek fire
that burned about 16,500 acres last summer in the same area near the
Kuskokwim River.
About
80 firefighters in four crews were working to protect Native
allotments and two cabins on Wednesday. White Mountain’s initial
attack crew and crews from Lower Kalskag, Upper Kalskag and Nondalton
were on the scene.
More
holdovers
On
the Kenai Peninsula, all but one of the holdovers were found in the
burn area of the Card Street fire that scorched almost 8,900 acres
last year near Soldotna. The exception was a holdover from the Funny
River fire, which burned almost 200,000 acres – two years ago.
There
is also a holdover in the Mat-Su from last year’s Sockeye fire.
Here
are the five biggest Alaska wildfire seasons on record:
2004: 701
fires, 6.6 million acres
2015:
768 fires, 5.1 million acres
1957:
391 fires, 5 million acres
1939:
200 fires, 5 million acres
2005:
624 fires, 4.6 million acres
Related
stories from around the North:
Warming,
fires, warming, fires: How tundra wildfires could create an
unstoppable cycle
Yereth
Rosen, Alaska Dispatch News
2007.
Anaktuvuk River Fire, North Slope, Alaska. (Alaska Fire Service).
When
lightning sparked a big fire in the tundra of Alaska’s Arctic North
Slope nine years ago, scientists were stunned.
The
Anaktuvuk River fire grew to more than 400 square miles and burned
for months. It was bigger than the cumulative total of all prior
North Slope tundra fires dating back to the 1950s.
If
Alaska’s warming trend continues, such fires will no longer be so
extraordinary, according to a new analysis led by University of
Montana researchers.
Increased
probability of fires
Their study,
published online in the Sweden-based journal Ecography, uses past
fire behavior and conditions to calculate probabilities of wildfires
in 30-year timespans. If July temperatures average 13.4 degrees
Celsius (56.1 degrees Fahrenheit) and moisture levels are relatively
low, wildfires will become significantly more frequent, according to
the analysis.
“The
probability that an area will burn increases a lot,” said co-author
Philip Higuera, an associate professor of fire ecology at the
University of Montana.
The
biggest jump in probability of big fires is for areas that
don’t typically burn — the usually moist tundra of the North
Slope and similar areas in western Alaska. If the 13.4-degree
threshold is reached there, the probability calculations predict up
to a fourfold increase in wildfire.
‘Unprecedented’
fire danger
In
tundra regions like the North Slope and the Yukon-Kuskokwim Delta,
the fire danger will be “unprecedented” compared to the last
6,000 to 32,000 years, the study says.
The
Anaktuvuk River fire in the northern Brooks Range foothills
might have been a signal of what is to come.
The
2007 Anaktuvuk River fire, North Slope, Alaska, near the village of
Anaktuvuk Pass. (Michelle Mack)
The
2007 fire was probably the first for that area in 6,500 years,
according to scientific evidence examined later, Higuera said. But
the wait for the next big burn won’t be nearly as long, according
to the evidence gathered in the study.
“That’s
what the projections suggest, that we would expect to see more of
those,” Higuera said.
More
frequent fires
By
the late part of this century, wildfires will burn more
frequently in nearly all of Alaska, the calculations predict; in a
wide swath of the state, the probability of fires will more than
double by the middle of the century.
In
some places — chiefly, the Interior Alaska boreal forest,
where fires are already frequent — the increases
may be already underway,
Higuera said. Several past studies point
to that same conclusion, he said.
Fairbanks
has already passed the 13.4 degree Celsius threshold for average July
temperatures, and Fort Yukon in the eastern Interior region is
expected to reach that point by the end of this decade, according to
projections by the University of Alaska Fairbanks’ Scenarios
Network for Alaska and Arctic Planning —
the same set of projections used in the study to calculate future
fire probabilities.
Temperature
thresholds
In
other parts of Alaska, the July temperature threshold is in reach.
Bethel,
the biggest community in the Yukon-Kuskokwim region, and Kotzebue in
northwestern Alaska, will soon be at the July temperature threshold,
even if global greenhouse gas emissions are reduced from current
levels, according to the SNAP projections. Farther north, communities
like Anaktuvuk Pass and Nuiqsut could have July temperatures
averaging above 13.4 degrees by the late part of century, according
to the SNAP projections.
While
a warming climate primes Alaska for more frequent wildfires, the
fires themselves contribute to warming — and create yet more
favorable fire conditions.
Smoke
effect
Smoke
from wildfires has deposited soot particles onto sea ice, which is
already fragile for this time of year compared to recent averages.
Darkened ice and snow melts faster, further weakening the ice
coverage.
Feedback
loop
The
darkened surface left by tundra fires reduces the ground’s ability
to reflect solar energy back into space, a measure called
“albedo,”
scientists say. It took four years for the area charred by the
Anaktuvuk River fire to return to pre-fire albedo levels, says a new
study by
scientists from the Michigan Tech Research Institute. Even a
much-smaller tundra fire in the Brooks Range foothills, the 2012
Kucher Creek fire, reduced albedo, causing solar heat to be absorbed
rather than reflected back, says the study, published in the Journal
of Geophysical Research Biogeosciences.
That
could lead to future warming, possibly in a significant way, the
study says.
The
University of Montana-led study calculating future frequency is not a
forecast for the coming season or for any year in particular, Higuera
said. Instead, the study looks at decades-long trends and cycles, he
said. More immediate predictions are available in the national
wildfire outlook,
which forecasts a fairly normal fire season this year for Alaska.
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