Major melt in the midst of winter. Doesn’t sound quite right, does it? We tend to think of winter as the time of freezing, as the time of ice accumulation. Not the time of melt and thaw.
Now try this — major melt in Alaska in the midst of winter. Average temperatures 40 degrees hotter than normal in the midst of winter. Rainfall over snow and ice causing avalanches, major road blockages and ice dams to rivers in the midst of winter.
In this instance we have been transported from the somewhat odd into a reality that is completely outside of our previously ‘normal’ context. In this instance we are transported to a time that may well seem like the beginning of the end of the age of ice on planet Earth.
And yet this is exactly what is happening: one of the coldest regions on the planet is experiencing melt and related record heat in January.
For the state of Alaska, the consequences are a strange and freakish winter heat wave, one that features the extreme temperatures mentioned above. For the city of Valdez, as we shall see below, the situation is far more stark.
(Massive Avalanche set off by rainfall, winter warmth, cutting off Richardson Highway to Valdez Alaska and forming a dangerous ice dam of the ironically named Keystone Canyon’s Lowe River. Image source: Alaska Department of Transportation and Public Facilities.)
Hottest ever Winter-time Temperatures for Alaska
On Sunday, a collapse event that flooded the Arctic with heat and ripped the polar vortex in half began. A freakish high amplitude ridge in the Jet Stream that had been pumping warmth over Alaska and into the Arctic for ten months running strengthened. The result was that many regions throughout the state experienced their hottest temperatures ever recorded for that day, month, or season.
According to reports from Weather Underground, Homer Alaska, for example, experienced an all time record high for the day of 55 degrees Fahrenheit, 4 degrees hotter than the previous all-time high set just a few years earlier. And Homer was just one of the many cities sitting in a broad region of extraordinary, 40 degree hotter than normal temperatures. A region extending from the interior to the southern and western coasts. Bolio Lake Range, about 100 miles south of Fairbanks in central Alaska, saw temperatures rocket to 60 degrees, just 2 degrees short of the all-time record high for any part of the state during January (the previous record high of 62 was set in Petersburg, nearly 700 miles to the south and east).
Typically colder high mountain regions also experienced record warmth for the day. A zone 10,600 feet above Fairbanks hit 32 degrees Fahrenheit on Sunday, the highest temperature ever measured for this region during any winter-time period from November through February.
Even before the most recent extreme Arctic temperature spike, January saw numerous powerful heat influxes for Alaska with Nome, Denali Park, Palmer, Homer, Alyseka, Seward, and Talkeetna each setting all-time record high temperatures during the month.
These records come on the back of a long period of rapidly increasing Alaskan heat stretching all the way back to the 1970s. In many cases, we are seeing all-time record highs broken with 5-10 year frequency. In the most extreme cases, these records fall again after only standing for 1-5 years.
Taken in this context, what we are seeing is the freakish continuation of an ongoing period of inexorable Arctic warming providing yet one more major insult to the Alaskan climate during the winter of 2013-2014.
Rain and Melt Sets off Major, Spring-like, Outflows From Streams and Rivers
The same anomalous Jet Stream pattern that has acted as a conveyer belt continuously transporting heat into the high north over Alaska has brought with it an almost endless series of rain events to coastal Alaska. Storm after storm, fueled by heat and high rates of evaporation over the northern Pacific, slammed into the Alaskan coastline, disgorging record levels of precipitation.
With temperatures freakishly high, mirroring conditions typically present during late spring or early summer, much of this precipitation fell in the form of rain. Valdez, Alaska, for example, has likely experienced its wettest January ever with rainfall measures just 1.35 inches short of the record on Sunday and a series of strong storms rushing into the city on Monday and Tuesday. Given the nearly endless train of storms lining up to sweep over Valdez, it is possible that its previous record of 15.18 inches for January could easily be surpassed by an inch or two at month-end.
The storms and cloudiness make it difficult to peer down and get a good view of what all this heat and rainfall is doing to the Alaskan snow and ice pack. But, for brief respite, on January 25th, just ahead of the most recent influx of rain and warmth, the clouds cleared, revealing the land and sea surface. And what we witness is extraordinary: More
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