One very interesting aspect of the floods of milder air surging up to the Pole the past fall involves the fact that on the western side the winds have often been south on the east coast of Greenland, where winds are usually north. This creates all sorts of confusion, in the contentious world of sea-ice debates, as the south winds have effects counter-intuitive to what I would initially expect, (which is that south winds are warm winds and lead to less ice.)
It is undeniable that a lot more mild air headed up to the Pole than we have ever seen, since records began to be kept in 1958. The temperatures-north-of-80°-latitude is quite impressive, in terms of warmth as winter approached.
There was a lot of Alarmist hoopla about this warmth, as there should be, as it represents a change in usual patterns. I have talked about how the Quiet Sun might be the cause, rather than CO2, in prior posts, but prefer to think in new directions in this post.
One graph I would like to see produced is a graph of temperatures between 70° and 80° north latitude, as well as one for temperatures between 60° and 70° north latitude. The trouble with the above graph is that it is focused in the center of the Arctic Sea, and many times this past autumn the coldest temperatures were around the edges. In fact the coldest temperatures, well below normal, were south of 70°, especially in Asia, where records for cold were set. Therefore the above graph is not seeing the big picture.
However the above graph does demonstrate an “unpresidented” (since 1958) surge of milder-than-normal air was brought up to the Pole. (When we say “mild” we need to remember “normal” on the Arctic Sea is -30°C, and therefore temperatures can be twenty degrees above normal, and still cold enough to form sea-ice.)
The primary cause of reduced sea-ice extent has not been the lack of ice forming, but rather that the thin skim of ice at the edges has been smashed north by the strong south winds both in Barents Sea and in Bering Strait. (At times those winds have been above freezing when they first arrive at the Pole, but the primary reason for the retreat of the ice is that it is smashed north. After all, when the ice first forms it is only inches thick, and we are talking about gales with waves 15-25 feet tall.) As soon as the winds shift to the north the sea-ice expands south with remarkable speed, amounting to many miles each day, but then it just as swiftly retreats north again when winds turn south again.
It is good fun to watch those who cheer the growth of ice and those who cheer the reduction of ice, because their mood swings can be tremendous in such situations. I guess you could call them bipolar (Ha ha).
In actual fact the “surge” creates all sorts of changes that are somewhat hideously complicated, involving changes in the amount open water, the structure of that water, the currents of that water, and the structure of the ice atop that water when it at last forms. Allow me to quickly list some, as they occur to me, off the top of my head.
A.) Open water loses more heat than ice-covered water, and therefore the water may be at a lower temperature when it is finally frozen over. This means a lot, for most melting comes from beneath, the following summer, and waters even a half degree colder will melt the ice more slowly.
B.) Protected waters are able to stratify, and layers of milder but less saline water can move considerable distances north, to hasten the melt the next summer. However wind-churned waters are less able to stratify, not only due to turbulence at the surface, but also because when the wind shifts to a frigid direction and the water is cooled and frozen with great speed, plumes of saline, super-cooled water sink.
C.) Regarding the sinking waters, if they are sinking in areas where not much sinking usually occurs, (for example further north when water is open further north), it disturbs the ordinary flow, and makes a mess of my nice, neat charts.
D.) Regarding the flow and my nice, neat charts, having water exposed to strong winds allows surface waters to, at times, move opposite to the ordinary flow of more usual currents. On occasion this can transport ice as well, and if the ice melts it cools the water in its new location, as well as making the water less saline. (A good example occurred last winter in Fram Strait, where usually a cold current drives south, carrying ice down the east coast of Greenland, as a warm current drives north on the east side of the Strait, keeping the west side of Svalbard ice-free. However last winter unusual west winds shifted masses of ice across Fram Strait, from the cold west side to the warm east side, where the ice swiftly melted, reducing the sea-ice extent but greatly cooling the warmer current, even to a point where sank beneath northern waters further south than usual.)
E.) A final effect of the “surge” is increased precipitation, which is almost always snow during the winter. The Pole is described as a “desert”, and often sea-ice has very little snow on top of it. Increased snow has contrary effects, making the ice less-thick during the winter because the snow insulates the sea-water under the ice and keeps the ice from thickening, but during the summer snow reflects the sunshine and slows the thinning of the ice, (and also, even when it finally turns to slush under the 24-hour-sunshine, it uses up a lot of available heat, turning it into latent heat during the phase change from solid to liquid.)
F.) I’m sure there are other complexities I’ve forgotten. (Evaporation on open waters springs to mind.)
It is the subject of increased precipitation that has grabbed my interest today. I’ve read several Alarmist posts about how mild it has been up in Svalbard, and how the waters around the island are all but ice-free, but I’ve read little about the effect all the moist air, and its result snow, will have.
For one thing, any snow that falls on land seems to be dismissed from most Alarmist calculations, concerning the albedo of ice and its ability to reflect sunlight during the melt season. Currently there is no or very little sunlight to reflect to the north, and to the south above-normal snows are reflecting a lot of sunshine, but I see no calculating being done on how this could be cooling the planet.
Secondly a great deal of stress is put on Greenland’s icecap melting away, by some Alarmists. The “surge” is not having that effect.
The “surge” has at times extended to the east coast of Greenland, and this indeed does reduce the ice-extent graph, for the southbound current on Greenland’s east coast is slowed or even briefly stopped (at the surface) by southerly gales. The sea-ice that flows down that coast is slowed, and this reduces the “extent”. However that leaves more ice to the north to make extent’s higher next summer. (I should note that the “surge” has also been mild enough to slow the growth of “home grown ice”, which does not come from the northbut grows in place, along Greenland’s east coast.)
However the “surge” has also blown huge amounts of moisture inland in Greenland. Wven south winds accomplish this, but the passage of gales up the coast (part of the surge) has turned those winds southeast and even due east. The snowfall over southeast Greenland has greatly increased the amount of the “icecap”.
In fact, just as the mild temperatures at the Pole are “unprecedented”, so too is the yearly increase of mass atop Greenland accumulated at an “unprecedented” rate.
I should mention Greenland is shaped like a bowl, and the icecap makes it like an overfilled bowl. Ice cannot “slide” off Greenland any more than ice can “slide” out of a bowl of ice-cream (unless you mistakenly fill your bowl when it is upside down). Most ice escapes Greenland’s bowl because it is heaped up to over 10,000 feet high, which creates such pressure that it is squeezed between the mountains around the edge as massive glaciers that reach the sea.
Judging from the above graph Greenland is in no danger of melting. If anything it is increasing, and the glaciers around the edge will be exuding more and not less ice. The only hope the Alarmists have is to point out places where the ice extends out to sea, for if the ice is exuded faster then more great icebergs will break off, and Alarmists can point at them and draw the wrong conclusions.