Arctic
‘Heat Wave’ to Rip Polar Vortex in Half, Shatter Alaska’s
All-Time Record High for January?
23
February, 2014
62
Degrees Fahrenheit. That’s the all time record high for anywhere in
the state of Alaska for the month of January. 57 Degrees Fahrenheit.
That’s the temperature measured earlier this week in southern
Alaska.
And
forecasts call for warmer weather from Friday through Monday…
Across
Alaska, temperatures are as much a 30 degrees above average for this
time of year. This record winter warmth has pushed Alaska’s average
temperature, according
to reports from Anchorage,
to 24 degrees Fahrenheit. By comparison, the lower 48, hundreds of
miles to the south, is experiencing average temperatures of 22
degrees Fahrenheit. Though 24 degrees is not typically seen as a heat
wave, readings in the upper 50s and lower 60s for Alaska in January
may as well be. If these same temperature extremes were occurring
during summer, some parts of Alaska would be experiencing a 90+
degree scorcher.
Mangled
Jet Stream, Anomalous 10 Month Blocking Pattern to Blame
What
we are witnessing is what amounts to a ten month long warm air
invasion of the Arctic, with Alaska at ground zero. Human-caused
global warming has resulted in an amplification of polar temperatures
well above the typical average. Now the region is experiencing
readings that range of 15-30 degrees warmer than normal.
This
massive temperature increase (also associated
with a reduction of land and sea ice)
is causing a weakening in the polar Jet Stream which is allowing more
warm air to invade the Arctic from the south. Early last spring, a
weakness in the Jet resulted in a powerful and extraordinarily
persistent blocking pattern forming over Alaska. Warm air flooded
continuously up and over Alaska, occasionally penetrating deep into
the Arctic Ocean region. Heat
wave after heat wave impacted Alaska, which set numerous all-time
record high temperatures during the summer of 2013.
This
anomalous heat flooded
in and spilled out around the Arctic Circle,
disgorging so much hot air that the term ‘Arctic Heat Wave’
became common parlance. Now, this historic and extraordinary pattern
has continued for 1o months running. A kind of persistence that may
well give new meaning to the term blocking pattern.
The
wave pattern stretches so high into the upper latitudes that what we
are seeing is weather systems more often rise up from the south and
travel northward over Alaska and into the Arctic, than proceed in
their typical east-west progression.
The west-east weather train is
broken. And a strange south-north train from equator to Arctic is
instead set in place.
In
the above image sequence, provided by NASA, the heat and associated
moisture flow all the way from the equatorial region near Hawaii, up
over thousands of miles of Pacific Ocean waters before flooding on
through Alaska and into the high Arctic. The extraordinarily powerful
and persistent blocking pattern has linked the deep tropics to the
high Arctic in unprecedented and anomalous fashion. Especially when
one considers that the current pattern has
lasted for almost an entire year.
This
it the kind of extreme weather pattern that Dr.
Jennifer Francis warned about.
The kind of pattern Dr. Jeff Masters continues to point out in his
cutting edge blog — Weather
Underground.
In my view, we ignore Dr. Francis and Dr. Masters at our risk. Their
observations hold true to what is happening now and they are very
useful tools for predicting the weather of a world in which human
global warming has now become the primary driver of the world’s
climate. Without the actual and ongoing context that is human
warming, the few meteorologists still associated with climate change
deniers scramble to find the increasingly rare analogs in past
climate that match today’s extreme weather. But there is no analog
to warmest ever temperatures in Alaska and polar temperatures that
are now
hotter than they were at any time over at least the past 44,000
years.
And there is certainly no analog to CO2
levels higher than they’ve been at any time during the past 4.5
million years.
For
this is the disrupted Jet Stream pattern not only directly
responsible for the anomalous Arctic heat Alaska is now experiencing.
It is also the cause of colder air being driven out of the Arctic and
southward over the US, causing multiple cold snaps and extreme winter
weather events in the lower 48. For the warm air influx, both at the
surface and at the upper levels of the atmosphere, result
in multiple polar vortex collapse events.
Polar
Vortex to be Ripped in Half
And
we are in the midst of just such a polar vortex collapse now. Over
the past week, warmer air has flooded the high Arctic, weakening the
polar vortex as the center of cold air began to split and streamed
down over the continents. By Monday, these warm wedges of air,
driving up over both Svalbard in the east and Alaska in the west,
will have completely separated the polar vortex into two
disassociated cold centers.
In
essence, the polar vortex will have been ripped in half by a pincer
style warm air invasion from the south. Who knew that atmospheric
warming would come to mimic the battlefield tactics of Germans
rumbling over the fields of France during World War II? But here we
are:
In
the above image, we can plainly see the much warmer than normal air
wedge driving up from the south and over Alaska in association with
the now, ten month old, blocking pattern and related Rossby wave
feature over the Pacific and North America. A second, albeit weaker,
wedge drives in over Europe and across Svalbard. The net result is a
‘pincer’ of warm air invading the Arctic and cutting the polar
vortex in half.
Note
that one cold air vortex is predicted to be centered over Eastern
Canada near Hudson Bay (Monday). The other is shown to be driven
south to Russian Kamchatka near the Sea of Okhotsk. Perhaps
coincidentally, this cold air core is very close to the Amur region
of Russia and China that experienced a 150 year flood event just this
summer. A flood event also associated with anomalous Jet Stream
patterns linking polar, temperate, ocean and monsoonal storm patterns
(see Song
of Flood and Fire
and Requiem
for Flooded Cities).
Under
this pattern the Arctic and especially Alaska will continue to
experience record or near-record warmth, while the lower 48 continues
to suffer the repeated blows of extreme winter weather as the
conditions that are supposed to be affecting the Polar region are
instead mercilessly driven southward by a human caused warming and
polar vortex collapse event.
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