Alaska sinks as climate change thaws permafrost
The thawing of permafrost — frozen ground covering most of Alaska — doesn't just damage roads, buildings and airport runways. It also releases vast amounts of heat-trapping greenhouse gases.
- Global warming is accelerating the thawing of Alaska's permafrost
- This thawing emits vast amounts of heat-trapping carbon and methane
- Alaska is also seeing more wildfires and less summertime sea ice
8 October, 2013
NORTH
POLE, Alaska — Up the road from Santa Claus Lane, past the candy
cane-striped streetlamps, Cathy Richard's backyard has a problem that
not even elves — or the big guy in red — could fix.
The
wood deck moves up and down, like a slow-motion sleigh. "You
leave for work and when you come home, it can be 7 inches higher,"
says Richard, 36, a married bookkeeper and mom of three children.
She
knows the Grinch involved. Her home in this Fairbanks suburb, built
in 2007, sits on land that thaws and refreezes so the concrete
pillars holding up her deck have crumbled. The front walkway and
garage floor are also cracking, and the lumpy lawn has fissures.
Bad
news for Richard — and, for the rest of us. Warmer temperatures are
thawing the surface layer of land that covers most of Alaska and is
known as permafrost (frozen below for at least two years in a row.)
This thawing not only damages roads, buildings and airport runways,
but also releases vast amounts of greenhouse gases that further warm
the atmosphere — not just over Richard's house but worldwide.
The
nation's last frontier is — in many ways — its ground zero for
climate change. Alaska's temperatures are rising twice as fast as
those in the lower 48, prompting more sea ice to disappear in summer.
While this may eventually open the Northwest Passage to sought-after
tourism, oil exploration and trade, it also spells trouble as
wildfires increase, roads buckle and tribal villages sink into the
sea.
On Aug. 26, a worker with the Alaska Department of Transportation secures sheets of polystyrene insulation to a road in Fairbanks, Alaska, that was damaged by permafrost thawing and will be repaved on top of the insulation. The sheets will minimize thawing in the future.(Photo: Wendy Koch, USA TODAY)
USA
TODAY traveled to the Fairbanks area, where workers were busy
insulating thaw-damaged roads this summer amid a record number of
80-degree (or hotter) days, as the eighth stop in a year-long series
to explore how climate change is changing lives.
The
pace of permafrost thawing is "accelerating," says Vladimir
Romanovsky, who runs the University of Alaska's Permafrost Laboratory
in Fairbanks. He expects widespread degradation will start in a
decade or two. By mid-century, his models suggest, permafrost could
thaw in at least a third of Alaska and by 2100, in two-thirds of the
state.
"This
rapid thawing is unprecedented" and is largely due to
fossil-fuel emissions, says Kevin Schaefer of the National Snow and
Ice Data Center in Boulder, Colo. He says it's already emitting its
own heat-trapping carbon dioxide and methane, but the amount will
skyrocket in the next 20 to 30 years. "Once the emissions start,
they can't be turned off."
Telltale
signs are common — from huge potholes in parking lots to collapsed
hill slopes and leaning trees in what are called "drunken
forests" in Denali National Park, home of the majestic Mount
McKinley — North America's tallest peak.
"You
can see and hear the ice melting," says Ted Schuur, a permafrost
expert at the University of Florida who's doing field studies in
central Alaska. He says permafrost contains soil and plant matter as
well as chunks of ice as big as cars. When the ice melts, the ground
sinks. He's seen it with his own cabin near Fairbanks, which was
listing until he leveled one side with adjustable foundation piers.
Ruth
Macchione's old home in Fairbanks, Alaska, shown here on Aug. 26, is
sinking into the ground. Her late husband hand-built it with sturdy
logs, but the house rests on permafrost -- the top layer of which
freezes and thaws each year -- so it's now tilted.(Photo: Wendy Koch,
USA TODAY)
Ruth
Macchione, an 84-year-old grandmother in Fairbanks, has also
witnessed the damage. She and her late husband raised nine children
in a home he built more than 50 years ago with logs that he sanded
and polished. He lived there until his death in 1986 and she stayed
until 2000, when she was forced to move to a small new house next
door.
"Everything's
tilted," she says, gazing at the old family home that is sinking
into the ground. For years, she put furniture and other items on
blocks to try to level them, but it got to the point where she could
no longer open or close the doors.
"It's
a shame," she says sadly of her partly submerged homestead. "It
was well-built."
Permafrost
thawing emits greenhouse gases
Permafrost
has existed for eons. During the last Ice Age, it swept as far south
as Missouri and Illinois. Today, most of it is located in Russia and
Canada, but the United States accounts for 6% of the world's total —
almost all of which exists in Alaska. It has a top "active"
layer that thaws and refreezes each year and a deeper layer that
remains frozen and stores organic carbon from decaying plants and
animals — possibly twice as much carbon as in the atmosphere.
As
air temperatures rise, the top layer thickens and more thawing
occurs; its pace depends on local conditions. Some areas such as
Fairbanks are particularly vulnerable, because the ground temperature
now hovers near the thaw point so the permafrost is less stable and
thaws less evenly.
The perils of permafrost have long been known. Back in the early 1970s, government scientists insisted that parts of the Trans-Alaska Pipeline be built above ground with refrigerated supports.The pipeline's oil is hot and, if buried underground in permafrost, could help thaw the top layer and cause potential spills.
Yet
scientists have just begun in the past five to 10 years to figure out
how much carbon is stored in the permafrost and what its accelerated
thawing will mean for climate change — and vice versa.
"It's
like burning fossil fuels," says Schaefer. He and other
permafrost experts have varying estimates on how much carbon dioxide
and methane will be released into the atmosphere from thawing. Yet
they agree climate change is exacerbating the problem and creating a
"feedback loop" or vicious circle in which thawing then
exacerbates global warming.
"We're
on the edge of a major transition point," Schuur says, pointing
to a 2013 report he authored that found tundras worldwide may already
be emitting more carbon than they absorb. He says global permafrost
emissions will be significant — akin to those from current
deforestation — but probably much less than those from power
plants, cars and other burning of oil and gas.
These
emissions weren't included in the global warming estimates developed
by the Intergovernmental Panel on Climate Change (IPCC) and released
in September as the first part of its Fifth Assessment Report. The
report, which said with heightened certainty that humans are
responsible for the planet's rising temperatures, serves as a basis
for negotiating future climate treaties.
Many
Alaskans are skeptical about the climate link. "Permafrost has
been thawing since the last Ice Age," says Jeff Curley, an
engineer for the Alaska Department of Transportation, saying its
amount depends on naturally-occurring variability. He notes the
state's temperatures have fluctuated every 30 or so years.
"When
I'm in Alaska, I stop talking about climate change," Schuur
says, adding the term has become politically charged. Still, he says
Alaskans are deeply concerned about permafrost changes.
"In
our region, roads affected by permafrost thawing are very common,"
Curley says. "There are places around Fairbanks where there's
asphalt 10 feet thick, because they were filled in to keep leveling
off the road on an annual basis."
Jack
Hebert, president of the non-profit Cold Climate House Research
Center in Fairbanks, shows on Aug. 27 the triple-paned windows and
other materials his staff recommends in building homes that are
resilient and energy-efficient.(Photo: Wendy Koch, USA TODAY)
Sea
ice loss poses other problems
Permafrost
isn't Alaska's only climate problem. As its temperatures rise (up 3.4
degrees Fahrenheit year-round in the past 60 years and 6 degrees
Fahrenheit in the winter), there's not enough rain to offset the
higher amount of evaporation, so surface soils dry up — a drying
amplified by thawing permafrost. The result? Increased risk of
wildfires.
"All
climate impacts are connected to each other," says Sarah
Trainor, who directs the Alaska Center for Climate Assessment and
Policy at the University of Alaska, noting the state has had more
large wildfires in the past two decades than in the prior 40 years.
Wildfires emit their own greenhouse gases that intensify global
warming.
Declining
sea ice creates another vicious circle. Most of the world's sea ice
is in the Arctic, and since it reflects sunlight (seawater absorbs
it), its loss will accelerate northern warming. And, in turn, higher
temperature will melt more ice.
This
has happened dramatically in the past 30 years, according to
measurements in September, when the extent of sea ice reaches its
annual low after a summer of heat. Arctic sea ice hit an all-time low
in Sept. 2012 but recovered somewhat last month.
"We
could be looking at summers with essentially no sea ice on the Arctic
Ocean only a few decades from now," Mark Serreze, director of
the University of Colorado-Boulder's National Snow and Ice Data
Center, said in announcing its 2013 satellite measurements. Despite
yearly ups and downs, he says the long-term trend is downward.
The
loss of sea ice offers tantalizing trade opportunities, because it
could make the Northwest Passage navigable more often in summer. This
sea route across the Arctic Ocean hugs Alaska's coast and can now be
crossed only about every seven summers. Sought by explorers for
centuries as a short-cut between Europe and Asia, it could be about
50% fewer nautical miles than a trip via the Panama Canal.
Yet
while the loss of sea ice could open coastal Alaska to more oil
exploration, tourism and shipping, it's not likely to help native
Alaskans, says Laurence Smith, a geography professor at the
University of California-Los Angeles. He says melting ice may open up
the sea but close off the land. Because much of Alaska is traversed
in winter by ice — rather than paved — roads, he says its
interior will become less accessible.
"We're
more likely to see an abandonment of these northern landscapes,"
says Smith, author of The World in 2050: Four Forces Shaping
Civilization's Northern Future.
Schuur
sees sea ice loss as a huge problem but worries more about
permafrost, because the latter is not as well monitored. "It's a
sleeping giant that affects us all."
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