Saturday, February 4, 2017

Arctic Sea Ice Remains Totally Lame

This chart shows the departure from normal of
"freezing degree days" in the Arctic. It reflects how
much the accumulated amount of freezing in the winter
in the Arctic compares normal. The black line on the
left is this year, the other lines are previous years. 
This story has been cropping up repeatedly for more than a year now, and the fact this still has legs is frightening.

You've probably seen several posts in this here blog thingy in which we fret about a dearth of Arctic sea ice.

The problem is persisting just as strongly as a more than year long spell of incredible warmth in the Arctic.

Of course, we all know the warmer it is, the slower the pace of ice formation up there.

Weather patterns this winter have favored occasional intrusions of relatively warm air into the Arctic at a time of year the region is normally in a pitch dark deep freeze.

Temperatures during these spells have flirted with 32 degrees near the North Pole, which isn't great if you want to manufacture ice.

This week, weather forecasts indicate another big shot of super warm air to invade the area near the North Pole.

The Arctic and Antarctic are probably more prone than anywhere on Earth to wild, extreme shifts in weather and climate.

Most scientists are pretty sure that part of this series of super warm spells up there are natural variability. That means that weird warm spells are bound to happen from time to time, and sometimes they can last awhile. And cause a temporary decine in ice coverage at the top of the world.

But these repeated bouts of Arctic "warmth" haven't been observed this persistently and this frequently in modern records. The consensus is climate change is messing with things, making the extreme warm spells even more extreme, and the cold spells not as bad as they once were.

There probably will be temporary shifts in which the ice extent in the Arctic temporarily recovers somewhat. There's bound to be winters in which weather patterns favor more cold air - with or without climate change.

And there will be years in which the summer melt season is lackluster. (2016 was kind of like that. The spring started with record low sea ice extent, but the summer warmth in the Arctic was - meh! - so by the time September rolled around, the sea ice extent was no longer at a record low, but still damn close to it. )

Regardless, the Washington Post's Capitol Weather Gang reports scientists are stunned by the level of warmth and lack of ice this winter in the Arctic.

Capitol Weather Gang cites this:

"After studying the Arctic and its climate for three and a half decades, I have concluded that what has happened over the last year goes beyond even the extreme," wrote Mark Serreze, director of the National Snow and Ice Data Center," in an essay in Earth magazine.

As Serreze notes, part of what's going on in the Arctic is just random extreme weather events, always happened, always will. However, global warming is superimposed on these extremes, making them more out of line than ever observed before.

Unusual weather patterns that have prevented frigid high pressure systems from settling over the Arctic, combined with repeated storms that pumped in warm air from the south, are the immediate blame for this winter's excessive Arctic warmth.

Almost nobody expects this weather pattern to continue forever, so we're sure to get some winters in which Arctic sea ice recovers somewhat.

But the overall trend for the next few decades will be less and less sea ice up in the Arctic. Eventually - nobody is exactly sure when - the Arctic Ocean will be pretty much free of ice during the summer.

Which will screw up weather patterns all over the world, so we need to increasinglt expect the unexpected over the next years and decades where we live in the mid-latitudes.

The Arctic is not Vegas: What happens in the Arctic doesn't stay in the Arctic.

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