Arctic
Heatwaves Rise to Threaten Sea Ice as Lake Baikal Wildfires Re-Ignite
18
May, 2014
According
to model forecasts, Arctic heatwaves are forming that will,
throughout this coming week, bring 50-70 degree (F) temperatures to
the shores of the East Siberian and Laptev Seas, the estuaries of the
Kara and on through Arctic Eastern Russia to Coastal Scandinavia.
These heat pulses will push a series of wedges of above-freezing
temperatures across the Arctic Ocean zones of the Chukchi, East
Siberian, Laptev and Kara Seas to within a few hundred miles of the
North Pole, creating conditions that set up the potential for a
severe early-season weakening of sea ice.
They
are the most recent in a long train of severe warming events arising
out of a wide region of Northwest North America and Eastern Asia
since at least late last fall. The heat waves have continued to ride
up weaknesses in the Jet Stream and deliver warmth to the High
Arctic, creating havoc for Arctic climes. During Winter, the
heat pulses collapsed the Polar Vortex and sent
Arctic temperature anomalies spiking to 5-6+ degrees Celsius or
greater above the already hotter than normal 1979 to 2000 average
even as they set off a series of heat-related weather emergencies for
Alaska.
Triple
Arctic Heatwaves
With
the emergence of late spring, high temperature anomalies typically
cool in the Arctic as polar amplification seasonally fades. However,
the two Jet Stream weaknesses have continued to provide heat
transport and push Arctic temperatures above normal and into
ice-threatening ranges. Now, a third hot ridge, this one over Western
Russia and Eastern Europe, has emerged and strengthened to provide
yet one more Arctic heat delivery engine:
(Triple
Arctic Heatwaves — one over the East Siberian Region of extreme
northern Yakutia, one over Western Russia and Eastern Europe, and a
final one that, in this May 24 forecast, is centered in Canada west
of Hudson Bay and extending toward the Canadian Arctic Archipelago.
Note the long tongue of above freezing temperatures extending into
the Arctic Ocean from the East Siberian and Laptev Seas. In the
current picture, it is night over Alaska and Canada, day over Russia.
Information Source: Global
Forecast System Model.
Image source: University
of Maine.)
This
combination of gathering heat waves has frequently pushed late-spring
Arctic temperature anomalies into the range of 1 to 2 C above average
with local areas forecast to see between 10-20 C or higher
departures. It is extraordinary heat for late spring. A gathering
event that appears to be setting up for a major blow to Arctic sea
ice.
Smoke
on the Waters of Lake Baikal
The
formation of what is now a growing and broad-ranging Arctic heatwave
was, this weekend, heralded by a return to extreme and anomalous
wildfires in the region of Lake Baikal, Russia. Ever
since April, immense fires have been springing up in this region
requiring massive response from an Army of Russian firefighters.
Over the past two weeks, the fires have been held at bay by a
combination of Russian emergency response efforts and cloudier,
rainier conditions.
But,
over the past two days, extreme seasonal heat has returned to this
vulnerable region, an area where winter warmth, early melt, and
thawing tundra have provided ample and excessive heat and fuel
sources for the ignition of extreme wildfires. By today, the fires
near Lake Baikal in Yakutia were both massive and intense featuring
numerous blazes with 20 mile or greater fire fronts as the entire
burning region cast off a tail of dark and heavy smoke stretching
more than 1,500 miles west and north toward the Pacific Ocean:
(Lake
Baikal Fires May 18, 2014. Lake Biakal is in the lower center frame.
Width of frame is about 2,000 miles. Image source: LANCE-MODIS.)
This
early proliferation of fires, as hinted at above, is the continuation
of a massive event that began very early this spring and is likely to
continue to show intensification and emergence in the three Arctic
heatwave zones.
Fires
of this immense scope pose their own threat to ice in the form of
delivery of very high volumes of black soot that darken sea ice and
glacial ice sheets alike. This darkening is, yet one more, amplifying
feedback to climate change in the Arctic and remains a suspected
factor in the acceleration of Greenland ice sheet melt (See
Dark Snow).
With so many fires so early, the risk of a long, summer-period snow
and ice darkening is well on the rise, potentially playing a role in
what is now also a spiking risk of rapid melt pond formation.
Disposition
of Melt Ponds
A
recent study found that a proliferation of melt ponds during late
spring and early summer has preceded record melt seasons in all
instances between 2007 and now.
With current heat pulses and Arctic wildfires setting in place
conditions that may well result in the ignition of widespread very
early season melt pond formation in mid-to-late May, risks
for end season melt spikes are on the rise.
Regions impacted by these heat pulses and related early season albedo
loss are similar to areas showing widespread melt pond formation
prior to the massive 2012 sea ice collapse event (there has been
educated speculation over at the
Arctic Ice Blog that
the location of these melt ponds on the Russian side may have played
a key role in 2012′s massive melt).
The
Role of El Nino and Upping the Chances for a Near Zero Sea Ice Event
The
rise of El Nino in the Eastern Pacific is also likely playing a part
in these building heat waves. El Nino typically enhances high
amplitude Jet Stream ridge formation over Alaska and Canada.
Furthermore, in recent years, we’ve seen the tendency for ridge and
heat dome formation over Eastern Europe and Western Russia during El
Nino. So at least two of the three observed Arctic heat delivery
zones are likely getting a kick from what appears to be a strong El
Nino gathering in the Pacific.
If
El Nino arises and continues to increase atmospheric heat transfer to
the Arctic, to proliferate extreme wildfires, and to enhance early
loss of albedo, this year will, indeed, be a very bad one for Arctic
ice. Given observed and ongoing trends along these lines, we are
increasing our risk for a near-zero sea ice event by end of this
summer to 30%. Eyes turn to Greenland as well, since both loss of sea
ice cooling and a proliferation of early season fires can result in
compounding risks to the increasingly unstable glaciers of that
thawing land.
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