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Major Arctic Fire Outbreak — Number of Active Alaskan Wildfires Doubles in Just Five Days
25
June, 2015
Late
Sunday, there
were 146 active wildfires burning in Alaska,
as of Thursday afternoon, that
number had exploded to 291.
A
combination of record hot temperatures and unprecedented thunderstorm
activity over the Arctic state has provided numerous dry fuels and
lightning-based ignition sources over recent weeks. During the past
few days, conditions rapidly worsened as an extreme fire outbreak
absorbed all of the firefighting resources of Alaska and tapped a
substantial portion of other states’ resources as well.
As
of Wednesday afternoon, the NASA/MODIS satellite shot of Alaska
(below) showed much of the massive state shrouded under vast clouds
of steely gray smoke billowing up from the scores of wildfires
blazing beneath. A cloud so large it is now becoming entrained in the
Jet Stream and will likely blanket a large section of the Northern
Hemisphere in a brown-carbon haze.
(The
origin of a 3,000+ mile long cloud of smoke swirls over scores of
wildfires now burning throughout Alaska and Canada. Over the past
five days, the number of Alaskan wildfires alone has doubled — an
upshot of record Arctic heat in a record hot world. Image
source:LANCE-MODIS.)
According
to Alaska
Dispatch News,
conditions on the ground were rapidly worsening as 40 new fires
erupted on Wednesday. The swiftly expanding Tozitna
fire forced Tanana community residents to evacuate. Another town —
Nulato — was encircled by a 1,200-acre blaze Wednesday forcing its
airstrip to shut down.
The Nulato fire is now being battled by 100
firefighters working feverishly to save community structures.
Meanwhile, Kenai Peninsula residents breathed a tentative sigh of
relief as the Card Street fire and Willow’s Sockeye fire were
checked by active firefighting efforts.
Joining
what is now a massive, state-wide effort are firefighters sent from
Missouri today. The Missourians are added to a now national effort to
contain and control the raging Alaska blazes that, so far, have
consumed over 400,000 acres. Firefighters may get a little help —
with the weather predicted to back off record temperatures as storms
ride in from the Gulf of Alaska.
Global
Warming Intensifying Alaska Wildfires
But
conditions on the ground are making some firefighting efforts
extremely difficult. For not only do fire crews have to combat blazes
igniting in tradition fuels like boreal forests and tundra scrub,
they also must deal with fuels added by an ongoing permafrost thaw.
This thaw, set off by human-forced warming of the climate, unlocks
organic materials long frozen within the soil itself. These organic
materials form a carbon-rich peat-like layer beneath the top soil.
And like peat, the stuff is flammable when dried through the
increasingly warm Arctic Spring, Summer, and Fall. Once thawed and
dried, it creates an understory fuel that can keep blazes burning for
weeks, months, and sometimes years.
Throughout
the Arctic, there are hundreds of billions of tons of permafrost. And
much of it is now thawing at the southern edge and along the warming
coastlines of the Arctic Ocean. Of this permafrost, Alaska has more
than its fair share — with most of state soils covering a
carbon-fueled permafrost under-layer.
It’s
this combination of human-caused warming and the related unlocking of
permafrost fuels that has likely contributed to a substantial
increase in the number fires and area burned in Alaska over the last
60 years. For a
report published Wednesday by Climate Central has
now found that as temperatures warmed by 3 degrees Fahrenheit (1.7
Celsius) in Alaska over the past six decades (twice as fast as the
rest of the US) both the number of large wildfires and the area
consumed by fires within the state is dramatically increasing.
(Climate
Central’s June 24 report shows that the number of large Alaskan
wildfires has nearly doubled in recent decades when compared with
large wildfire frequency during the 1950s through the 1980s. Image
source: Climate
Central.)
Climate
Central notes:
The area burned in large wildfires each year is increasing. In just two years, 2004 and 2005, wildfires burned a larger area than in the 15 years from 1950-1964 combined. In particular, there has been a dramatic increase in wildfires larger than 10,000 acres but smaller than 50,000 acres.
Though
a 3 F (1.7 C) warming of Alaska over the past 60 years has already
provided significant additional heat and fuels, additional warming
through 2050 globally is predicted to be between 2 and 4 F (1.1 to
2.2 C) under moderate to severe additional fossil fuel emissions (RCP
4.5, RCP 6 and RCP 8.5). Due to polar amplification, warming in
Alaska is likely to be roughly twice the global average. And as a
result, fires throughout the state are only likely to grow more
extreme.
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