There is always a lag between the time an event occurs in the tropics and the time the effects of that event reach the Pole. But there is no lag, when it comes to the effect of the sunshine actually striking the Pole. Therefore the effects of the “Quiet Sun” at the Pole are immediate, in terms of sunshine, but lagged, in terms of the complex manner the Quiet Sun effects the temperature of the oceans at the equator.
I think we have seen this in the temperatures at the Pole. From the moment the sun started to get high and bright in arctic skies in May, the temperatures were below normal. Then, from the moment winter darkness begins to spread south from the Pole in September (and the sun can have very little effect at the Pole because it doesn’t shine) temperatures have been above normal.
It is common sense that the sun only effects the Pole directly when it is shining, (though certain people will make it more complex than it needs to be.) It is also common sense that as soon as the sun sets at the Pole something besides the sun must be involved, when it comes to transporting heat to the Pole.
The transport occurs via air masses. The planet is constantly attempting to achieve a balance, though arriving at a point where the entire planet is the same temperature is impossible. Just as we will always have our poor, we will always have our Poles. As the planet attempts to move all the equator’s heat to the Pole, it is attempting the impossible, and is in some ways like a socialist attempting to move the wealth of the rich to the poor. It even gets nasty, with hurricanes and gales, like socialists do with taxes. Unlike socialists, the result is a beautiful planet.
(In case you are wondering, I’m currently doing my taxes.)
The transport also occurs via ocean currents, but much more slowly. The heat we currently notice at the Pole largely comes from a meridional flow, where the jet stream develops loops that hurry the mixing of arctic air with tropical air. When the difference between the Pole and the Tropics is less pronounced there seems to be less need of mixing, and the jet stream gets less loopy, and that flow is called “zonal.”
I have been working on the idea, the past year, that there is a third flow, that creates an area of low pressure at the Pole which, for my amusement, I have dubbed “Ralph.” I suppose this third flow is actually an “extremely meridional” flow, but I’ve decided to call it a “Ralphal” flow, because I’ve always wanted to contribute something to science, and coining words is fun.
My assumption was that the Ralphal flow was prompted by a larger-than-nornal difference between the tropics and Pole, brought about by the very big El Nino in 2015. I further assumed that the sway in the direction of El Nino conditions would be followed by an equal-and-opposite sway in the direction of a La Nina, as that usually happens. But it didn’t. We had a feeble La Nina, not equal-and-opposite at all, and then the Pacific looked like it was heading right back to El Nino conditions. So all forecasts could get thrown right into the dumpster.
But then, even as I busily wiped the egg off my face and adjusted all my forecasts to expectations of an El Nino, that fickle Pacific flipped right back towards La Nina conditions. This is why so many quit attempting to forecast the weather. They don’t like having their sanity messed with. (Fortunately sanity is never anything I’ve had to worry about losing, being blessed with madness to begin with).
The long term effect of this La Nina will likely be to generate cooler air masses, which in a lagged way will make their way up to the Pole, but likely this change will take its sweet time to manifest. When we check to see if sea temperatures are below normal, we notice the southern hemisphere may be surprisingly cool but the northern hemisphere remains surprisingly warm.
With all that extra heat to the north, the planet had the urge to lose, and that tends to encourage the development of hurricanes and typhoons. The set up was one which made the Atlantic the place for them to develop this year, and the above map actually shows their effect on the Atlantic’s waters. The heat was sucked out of the water off the east coast of the USA. (To the north the water is warmer because the hurricanes prevented the up-welling of cold water south of Labrador and Nova Scotia.)
On a whole all the heat coming from the northern ocean made the planet milder, but that mildness was hurried to the Pole, to be lost to the growing dark of winter night. The favorite route was up through the North Atlantic past Norway, over Svalbard, which was well above normal in September, as Roy Spencer’s September air temperature map demonstrates.
The above map averages out some of the loopy shifting of the jet. For example, at the start of September it was very cold in the east of the USA, with unusually early snows on peaks not far north of where I live, and even a few spots of late August frost, but by the end of September we were midst a heat wave, and the unusually early snows had shifted to the west of the USA. Result? The map averages the extremes out, and most of the USA looks “normal”.
However Svalbard, at the top of the map, was the most “above-average” place on earth. (Not that anyone went swimming in the icewater.) This is a definate sign of a Ralphal flow, and we did see Ralph incarnating up over the Pole, even as a decent gale for a time. (September 21 map below)
This flow continues to fascinate me, but I continue to think it must be at its end. Eventually the effects of the new La Nina will work north, and we’ll see what I imagine will be an abrupt shift to a more zonal flow. When? (Wait while I flip a coin.) My guess is February 13 at 6:00 PM, EST.
I’ve been saving maps since late August, and hope to go through what we’ve been seeing the past month in more detail. But first I have to face my blasted taxes. (I got an “extension” back when they were due on April 15, but it runs out on October 15. Even a great procrastinator like myself must someday face the music.)
For people interested in the sea-ice itself, it is growing back swiftly now.
As an interesting side-note, the mild air pushing north past Svalbard has pushed the ice away from its north coast, but this may actually be also preventing ice from being flushed south through Fram Strait and the east coast of Greenland. Though this reduces the sea-ice in the short term, in the long-term it keeps the ice up in the Arctic Sea, and increases “volume” if not “area” and “extent”.
Here’s a comparison with last year. (2016 to left; 2017 to right.)
One topic I hope to talk about in the future is the interesting way the sea-ice was jammed south last summer into the channels in the Canadian Archipelago. Some thick, multi-year ice flowed south to the east of Melville Island and across Parry Channel. This may enter the calculations of people attempting the Northwest Passage next summer. We can only cross our fingers and hope our poor, odd, battered O-buoy 14 camera survives another winter, in that area.