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| Fig. 1 Arctic Sea Ice Extent 4/9/19 |
I. The Question
In the previous post of this series what turned out to be a sharp drop in Arctic sea ice extent was sharp enough to make we wonder if the satellite equipment was having trouble (Mysterious Zones of The Arctic - 6).
The date of that sharp turn was March 4, 2019 (ibid @ Fig. 2 in that post).
As you can see at Fig. 1 in today's post, the sharp downward turn was not an equipment failure, it was an event that is not only quite real, it is a record-setting event:
"Arctic sea ice extent appears to have reached its maximum extent on March 13, marking the beginning of the sea ice melt season. Since the maximum, sea ice extent has been tracking at record low levels. In the Bering Sea, extent increased through the middle of March after setting record lows—only to drop sharply again.(NSIDC, Arctic Sea Ice News, emphasis added). "What is going on up there?" is a reasonable question.
...
The Bering Sea, which had been nearly ice free at the beginning of March, saw gains in extent through the middle of the month. However, those gains were short lived as extent dropped sharply during the last week of March. The Bering Sea typically reaches its maximum ice extent in late March or early April. This year, the maximum occurred in late January and was 34.5 percent below the 1981 to 2010 average maximum. These late-March sea ice extent losses in the Bering Sea accelerated the decline of total Arctic sea ice extent. By April 1, Arctic extent was at a record low for that date."
Especially since that decrease in ice (and snow) is not happening in Bob Dylan's country ("the country I come from is called The Midwest" - With God On Our Side).
In his country the ice is also falling, however, it is in the form of huge amounts of snow and hail falling from the sky which melts causing serious flooding.
Then, even more comes along:
The Midwestern United States has been experiencing major floods since mid-March 2019, primary along the Missouri River and its tributaries in Nebraska, Missouri, South Dakota, Iowa, and Kansas. The Mississippi River has also seen flooding, but to a lesser extent. From January until early March, average temperatures in the Midwest remained in the low 20 to 30 average degree Fahrenheit range, with record snowfall in many areas, including the early March blizzard, up to three feet on the ground in some areas. In Nebraska, over the course of three days (March 11 - March 13), temperatures rose to 60 degrees Fahrenheit, combined with 1.5 inches of rain. This quickly melted the snow, and the frozen ground was not able to absorb any meaningful amount, which led to unprecedented runoff into local streams and rivers. Many of the rivers were still frozen over with a thick layer of ice, which the powerful flow of water broke up and dislodged, creating massive chunks of ice that traveled downstream, acting as a "roiling plow". At least three people in Iowa and Nebraska have died.(2019 Midwestern U.S. floods), and then it did an encore:
The March 13 storm fit that definition and caused massive flooding in the Midwest, a blizzard in Colorado and Wyoming, and produced winds between 96 mph and 110 mph.(CBS News, Second major storm in a month). Doesn't it make you wonder why the far north Arctic is losing ice but the Midwest is getting way too much of it?
This week's storm [early April] is expected to be similar in intensity and in snowfall, but will likely fall short of the "bomb cyclone" designation, meteorologists said. CBS News contributing meteorologist Jeff Berardelli said on CBSN that it will become a "monster storm" when it hits the Plains.
"We're talking a blockbuster blizzard," Berardelli said. He expected it to start hitting the northern Plains on Wednesday and then slowly move across the region for at least two days."
II. The Answer
The answer is that when the Arctic warms some of the ice turns to water, and some of that becomes moisture in the atmosphere.
But more than that, it fractures the Polar Vortex, and pieces of it head south:
This current ultra cold snap is caused by a heat invasion into the Arctic, which once again broke up the Polar Vortex:(See ... Watching The Arctic Die, 2, 3, 4, 5).
"It might seem counterintuitive, but the dreaded polar vortex is bringing its icy grip to parts of the U.S. thanks to a sudden blast of warm air in the Arctic.(Associated Press, emphasis added; cf. Yahoo News).
Get used to it. The polar vortex has been wandering more often in recent years.
It all started with misplaced Moroccan heat. Last month, the normally super chilly air temperatures 20 miles above the North Pole rapidly rose by about 125 degrees (70 degrees Celsius), thanks to air flowing in from the south. It’s called 'sudden stratospheric warming.'"
Today for example, on April 7, 2018, at 10:00 AM it will be 40 deg. F at Nuuk, Greenland, at Anchorage, Alaska it will be 49 deg. F, but at Fort Worth, Texas will only be 37 deg. F.
Fig. 2 Breaking up
Nuuk, Greenland is up near the Arctic Circle which is some 4,667 km or 2,900 miles to the North (Fig. 3).
Yes, near the Arctic Circle it will be warmer than some southern parts of the United States.
This, as this series has pointed out, is because sections of the Polar Vortex are being separated by warmer air incursions into the Arctic.
This incursion is a disruption which is melting the sea ice cover of the Arctic Ice Cap, but is also breaking pieces of the vortex off.
Those separated bands of cold Arctic air go south to make unseasonably frigid temperatures in Europe and the U.S.
Whether Europe or America is impacted by the broken off portions of the Polar Vortex depends on where the vortex breaks up.
Fig. 3 Warmer in Greenland than in Texas
The spinning causes centripetal force which (when messed with) slings the sections out of the vortex like merry-go-rounds do to giggling kids at play on it; not knowing where in the circle they will end up when thrown off:
Under normal climate conditions, cold air is confined to the Arctic by the polar vortex winds, which circle counter-clockwise around the North Pole. As sea ice coverage decreases, the Arctic warms, high pressure builds, and the polar vortex weakens, sending cold air spilling southward into the mid-latitudes, bringing record cold and fierce snowstorms. At the same time, warm air will flow into the Arctic to replace the cold air spilling south, which drives more sea ice loss.(Wunderground, emphasis added). Or, as the government climate scientists put it:
‘Polar vortex’ is the new buzzword of 2014 for the millions of Americans learning about its role in producing record cold temperatures across the country. Meteorologists have known for years that the pattern of the polar vortex determines how much cold air escapes from the Arctic and makes its way to the U.S. during the winter.(Climate dot Gov). This knowledge helps explain that the Earth's climate is not getting colder as some have surmised by misinterpretation:
It’s happening again: In the dead of winter, warm air from the south is surging across the Arctic toward the North Pole.(Discover Magazine). This has been happening for quite a few years, but in recent years there have been increasing numbers of such events.
Today, weather models suggest that temperatures there have indeed soared to above freezing.
Meanwhile, cold polar air has spilled south into Eurasia and western North America. It’s almost as if someone left the Arctic’s refrigerator door open, allowing its frigid air to pour out and warm air to flow in.
[A] recent study shows that they are becoming more frequent and intense. In the study, scientists looked at winter air temperatures over the Arctic Ocean from 1893 to 2017. They found that since 1980, an additional six Arctic winter warming events have been occurring each winter at the North Pole, and they’re lasting about 12 hours longer, on average.
The previous post in this series is here.
