FEATURE-In Canada's far north, warm weather threatens vital ice road

By Susan Taylor
YELLOWKNIFE, Northwest Territories, Dec 24 (Reuters) - Each
winter, in the far reaches of Canada's north, a highway of ice
built atop frozen lakes and tundra acts as a supply lifeline to
remote diamond mines, bustling with traffic for a couple of
months before melting away in the spring.
This year, the world's busiest ice road is running late.
Unseasonably warm weather has set back ice formation on the
Tibbitt to Contwoyto Winter Road, named after the first and last
of hundreds of lakes on the route.
The road is still expected to open on schedule in late
January, but if current weather patterns continue that could
mean more work for crews trying to build the ice or cut the
road's already short period of operation.
Since its first season in 1982, the road has been vital to a
handful of mines scattered across Canada's Northwest Territories
(NWT), cut off by a maze of water and spongy tundra, otherwise
only reachable by air. Running 400 kilometers (248 miles), it
links to three diamond mines, stretching as far as 600 km when
it supplied a now-shuttered gold mine.
A shorter season could mean extra costs and inconvenience
for moving what amounted last year to 9,000 truckloads of
diesel, machines and mining supplies from the NWT's capital
city, Yellowknife.
To climate scientists, this year's late freeze could be a
harbinger of winters to come. It also raises the alarming
prospect of thawing permafrost - the frozen layer of soil
covering nearly half of Canada's landmass - which traps methane,
a greenhouse gas, which would only hasten warming.
This year's warmer temperatures may be connected to the El
Nino climate phenomenon, a periodic warming of Pacific Ocean
waters that has far-reaching effects.
It is Yellowknife's second warmest December on record, said
David Phillips, a senior climatologist at Environment Canada,
Canada's national weather service. So far, the average
temperature for this December is just above -15 Celsius,
marginally cooler than the -13 Celsius for December 2005, but
well above the mean of around -22 Celsius.
The NWT falls largely within the Mackenzie River Basin, an
area where winter temperatures have warmed by 4.5 degrees
Celsius over the last 68 years. "That's a sea change," said
Phillips. "It is just runaway warming."
For Ron Near, a retired Royal Canadian Mounted Police
officer who manages the road for a group of mining companies,
slow ice formation is a transportation problem.
Despite the warmer weather, he said it is not "panic time,"
and said he expects the road to start operating by the end of
January, with the heaviest loads waiting until a harder pack of
ice at the beginning of March.
"It has affected us some, but we're still within guidelines
of previous warmer years," he said. "It's just going to take
considerably more management this year to have success."

ALTERNATE ROUTES
Ice roads cross eight Arctic countries, and Canada alone has
5,400 km of them, critical to unlocking mineral wealth from
remote, harsh regions.
In the NWT, a vast land covering more than 1.3 million
square km with just 43,000 residents, diamonds were the biggest
contributor to the economy last year.
It is no surprise that the territorial government has been
pushing a partial all-season road on the southern end of the
mine supply route, which could extend the ice road's duration to
three months.
The C$170 million project may find favor with Canada's
recently elected Liberal government, which has pledged to spend
about C$10 billion annually on infrastructure for the next three
years.
But it is a long way from the ambitious idea first mooted in
the late 1950s by then-Prime Minister John Diefenbaker, who
campaigned for a "road to resources" running through NWT's
Mackenzie Valley and connecting to the Arctic coast.
More than a half century later, that vision for a Mackenzie
Valley Highway remains elusive. There is a road in the south
that extends as far as the town of Wrigley, and a C$300 million
road is being constructed to connect the far north town of
Inuvik with Tuktoyaktuk on the Arctic coast.
But there is no road connecting those two ends, a highway
that proponents say would assert Canada's Arctic sovereignty,
but would likely cost more than C$1.7 billion to build.
And advances on the Inuvik to Tuktoyaktuk project are slow
because construction occurs only in winter to minimize
permafrost damage. More than half the NWT permafrost is
sporadic, or discontinuous. It is easily disturbed, which in
turn produces ground thaw and instability.
Some 1,700 gigatonnes of carbon are held in permafrost soils
globally in the form of frozen organic matter, researchers from
the universities of Cambridge and Colorado said in September.
If that methane and carbon dioxide were released, it would
increase the risk of catastrophic weather, or loss of
agricultural land, causing up to $43 trillion in economic damage
globally by 2200, the study calculated.
By mid-century, rising temperatures may reduce the land in
Canada suitable for ice roads by 13 percent, or 400,000 square
km, concluded researchers at the University of California, Los
Angeles in a 2011 study published in Nature Climate Change.

RISKY FUTURE
The consequences of those warming temperatures pose an
additional risk to mining companies in the NWT, where a half
dozen planned mines are on hold due to multi-year low prices for
gold, rare earths and other metals.
A taste of the trouble warm winters cause came in 2006, when
the road closed after just 36 days. Miners spent more than C$100
million to charter flights for fuel and began talking seriously
about options like hovercraft and blimps.
To make the most of winter's cold, lightweight groomers are
now clearing snow that insulates and slows ice growth. Later,
amphibious tracked vehicles, called Hagglunds, will tow
ground-penetrating radar to measure ice thickness.
Crews may need to flood more of the road than normal to
quicken the freezing process this winter to overcome the warmer
weather, Near said.
The road, tracked by global positioning system technology,
now allows longer trailers that haul heavier loads and even has
'express' lanes, so returning trucks with empty loads can exceed
the 25 km per hour speed limit.
"We think about climate change all the time," said Near. But
he said he "learned a long time ago you can't control the
weather. You just have to be able to plan for it."