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| Temperatures in northern Alaska are likely to be a whopping 35 to 50 degrees above normal this week. While temperatures normally hover near 0 this time of year in that region, readings are likely to get above freezing. |
The good news for those who are winter-weary is that this will likely be the last time anyone in Vermont sees subzero temperatures until next November at the earliest.
The snow cover, deep in many areas, will begin to subside, starting today and continuing through the weekend amid thawing temperatures.
Despite the fact we will have a few wintry setbacks, spring is finally asserting itself in Vermont.
Meanwhile, it's been springlike up in parts of the Arctic all month. At least springlike by their standards. In parts of Alaska and northwestern Canada, this March will be far and away the warmest on record.
The ever-reliable Category 6 weather blog at Weather Underground has the rundown on this incredible Arctic "warmth."
Let's start with Utquiagvik, Alaska, formerly known as Barrow in the extreme northern tip of that state. The high temperature there yesterday was 32 degrees and the low, 17, which was almost exactly like the conditions we had here in Vermont on Tuesday. Seemingly not all that impressive.
But remember, this is the northern tip of Alaska. That 32 was record high for the date and Tuesday was 35 degrees warmer than normal in Utqiagvic. (Normal high there yesterday was minus 4, normal low, minus 17.
Utqiagvic is running 16 degrees above normal for March, and they are likely going to have the warmest March on record, and the first March with a mean temperature above zero, given the forecast of continued mild temperatures into early April.
It's not just Utqiagvic. Much of Alaska has been even hotter. Kotzebue, Alaska, about 300 miles southwest to the former Barrow is having a March that will end more than 20 degrees warmer than average, and a record high. Thaws in Kotzebue are rare and brief in March, but each of the past five days there have gotten above freezing. (Normal high this time of year around Kotzebue is around 10 degrees).
There have been some incredible March record highs in Alaska, the Northwest Territories of Canada and far western Siberia. Sitka, Alaska, reached 67 degrees this month. Yohin Lake, Northwest Territories, Canada sits just 400 miles from the Arctic Circle and managed to hit an incredible 71 degrees a week or so back. At the hour it was that warm in Yohin Lake, it was a degree or two cooler than that in Miami, Florida.
Tofino, British Columbia reached 76 degrees, which is a March record and would have been the all-time hottest reading there in April, too.
The odd warmth in Alaska is due largely to an odd and strangely persistent weather pattern that has brought repeated bursts of air from the south to the region. Plus, the Arctic is warming faster than the rest of the planet due to climate change.
Superimpose climate change on an odd, warm weather pattern and you really get some bizarre northern heat.
HOW IT AFFECTS US
If it seems this Arctic warmth is something that is happening too far away to affect many people and doesn't affect you at all, think again.
First of all, the lack of ice in the Bering Sea off western Alaska is having a wide range of effects. Ice usually prevents large storm waves from crashing ashore in western Alaska. With the lack of ice, the waves have been producing coastal flooding and erosion, notes the Anchorage Daily News.
Nobody can go crabbing, fishing and walrus hunting either.
This weather pattern has certainly affected the United States. The big northward bulge in the jet stream has created a big dip downstream. That means cold air masses have been able to easily move south from Canada. Air that's really warm for the season north of the Arctic Circle is cold for the season by the time it heads south to places like, well, Vermont.
Which helps explain why the weather was basically the same yesterday in Vermont as it was way up in the northern tip of Alaska.
This warm Arctic spring is reason to worry about the extent of Arctic ice, too.
Overall, despite the tiny amounts of ice in the Bering Sea, overall Arctic ice extent did not set any record lows this winter, which is a good thing. The ice extent probably peaked around March 13 and it was tied for the seventh lowest in the past 40 years. Not a terrific thing, but at least the amounts of ice didn't crash this year.
This week, the odd heat has expanded to include almost all of the Arctic. This is almost certainly a temporary thing, but it does start off the melt season awfully fast. If the trend were to continue well into the summer, we'd be a risk of setting a new record for lowest ice extent.
That's just speculation at the moment, anything can happen with the pace of this year's melt. It all depends upon what the weather pattern is like when summer really hits in June, July and August.
But if the Arctic ice continues to diminish, it will help keep making the weather patterns weirder and more extreme in places where we live in the mid-latitudes.
GREENLAND GLACIER GROWS
A good example of how natural cycles are superimposed on a warming climate is at the Jakobshavn glacier in Greenland.
The glacier became something of a poster child for climate change back in 2014, when it rapidly began to lose mass. It stunned people watching the climate, as glaciers like Jakobshavn, when they melt fast, contribute to sea level rise.
Well, guess what? The Jakobshavn glacier is growing again. Adding ice. So, no worries about climate change right? A Greenland glacier is actually growing!
Not so fast.
In the short term, the fact that Jakobshavn glacier is growing is a very good thing. It's not contributing to sea level rise, and is in fact slowing it by an imperceptible amount.
The glacier stopped shrinking and started expanding again because an ocean current bringing water to the spot where the glacier meets the ocean got much chillier starting around 2016. The water there is the coldest it's been since the 1980s, as Marshall Shepherd notes in Forbes.
There's a natural pattern called the North Atlantic Oscillation that makes the North Atlantic flip between cold and warm once every five, ten, fifteen, twenty years - it depends.
It's in the cold phase, so that's helping the glacier grow. Which leads Shepherd to a great point in his Forbes article. People who deny or are skeptical of climate change often say the climate changes naturally.
Climate scientist would respond by saying, Duh! They all already know climate changes naturally. always changes. As Shepherd writes:
"It's not 'either/or' with naturally-varying climate and human influences. it's 'and.''
Which is what we're seeing now with the Jakobshavn glacier, and the odd heat in Alaska.
Chances are, when the North Atlantic Oscillation flips again, that Jakobshavn glacier will begin to thaw again.
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