When I last posted (November 11) the last incarnation of “Ralph” had swung from northeast of Greenland over to the Kara Sea and then plunged down into Russia. In Ralph’s wake I expected high pressure to build over the Pole, but instead a weak wrong-way-flow persisted in Fram Stait, bringing Atlantic air north, and we could see the weak beginnings of a cross-polar-flow from the Atlantic to the Pacific.
This development continued until the cross-polar-flow grew quite strong.
This is a pretty odd map, as Greenland’s icecap usually grows high pressure that feeds a howling north wind that pushes ice south in Fram Strait, but now low pressure dominates the area and south winds persist in Fram Strait, both bringing mild air north and preventing the sea-ice from being flushed south (as it usually is.)
The temperature map show’s Ralph’s “signature” as mild air streaming north, on the Siberian side of the Pole, with the freezing isotherm pushed north of Svalbard, and the -5°C isotherm pushed close to the Pole. It was 25 degrees warmer over the Arctic Sea than to the south, over Siberia, where temperatures were below -30°C. Just northwest of Greenland temperature were down near -25°C. I expected a reincarnation of Ralph to arise as the mild air clashed with the cold. With pressures so high on the Siberian side I looked to the Canadian side, but the storm that brewed up looked to be an Atlantic storm north of Iceland.
Rather than taking the more usual west-to-east North Atlantic route (with a few loop-de-loops) over to Barents Sea and Kara Sea, this storm obstinately headed north into Fram Strait. It was determined to be Ralph, and not a North Atlantic storm.
Not only is this storm headed up to the Pole, but a secondary forming between Iceland and Norway may follow in its footsteps, heading a little west of due north and also passing through Fram Strait the wrong way.
This surge of mildness, even if not actually thawing the sea-ice, is slowing the ice’s growth and resulting in a totally amazing up-spike in the DMI temperatures-north-of-80°-latitude graph:
There have been impressive autumnal spikes other years (for example 1994 and 2000) but they were short lived and earlier. The mild temperatures this year have been “unprecedentedly” persistent.
That may be about to change, as the Arctic Oscillation is forecast to roller-coaster downwards into negative territory.
Of course, we’ll have to wait and see about this. Models can be wrong. However I’ve been expecting a pattern flip for some time. The persistence of this pattern has led to some extremes. Alarmists may be glad to see less sea-ice, but they also predicted the icecap of Greenland would shrink, but the same surges that bring mildness up through Fram Strait have led to amazing snows over Greenland, and, rather than shrinking, the icecap is growing at a rate that puts its yearly increase far ahead of schedule.
Also, though the surge makes it warm over the Pole, a sort of backwash beneath makes it amazingly cold over Asia, as much as twenty degrees Celsius below normal, in the anomaly map:
Some of this cold spills east out over to the Pacific, but it also backs west over Europe, which also shows a lot of cold anomalies.
I like the above map because it shows both the mild surge rushing northeast over Great Britain and Scandinavia, and the cold backwash heading south west over the rest of Europe. Also it shows the backwash even managed to cross the mild Mediterranean and get to Morocco and Algeria.
I always like to work the subject of Africa into my posts about Arctic Sea-Ice, but usually I have to wait until January. The picture below is from the mountains of Alegeria on November 8.
I often have the sense that, when things get this far out of kilter, they do mot merely swing back to normal, but rather swing to another extreme. Therefore I am as curious as ten cats about what the “pattern flip” will look like, if and when it ever gets around to happening.
Also I distrust my own experience when looking at certain maps. Sometimes a map doesn’t show the speed at which change is occurring. An analogy might be looking at the headlight of a train. Even if the headlight looks the same in two different situations, it makes a difference if the train is standing still, or coming right at you at a high rate of speed.
I am intrigued at the speed at which the water chilled in the north Pacific. In one way it looks like a ho-hum map of a warm PDO:
However the change happened so swiftly I wonder if the momentum might carry it right past a warm PDO into a cold one.
In any case, there’s a lot to watch and wonder about. Stay tuned.
EVENING UPDATES —Peak Of The Surge?—
I just had to include these two maps, as they tickle my imagination with wonder.
The newest Ralph’s secondary, just off the coast of Norway, is going (according to models) to take a sharp left. You often see this when gales loop-de-loop up there, however the models see this secondary failing to complete the loop, and instead trailing Ralph up to the Pole and dissipating up there. However the developing low just west of Iceland, which I suppose we could call the tertiary of Ralph, will head to Norway, turn sharply left, but not continue north, and instead just loop-de-loop. In fact (if you can trust models that far ahead), it will loop-de-loop-de-loop-de-loop, between Norway and the Kara Sea, for a solid week, which I suppose is a new pattern.
If you look at the above temperature map you can see the surge of mildness on the Eurasian side of the Pole. The freezing isotherm is well north of Svalbard, and not all that far from the Pole. (In and of itself this is not so terribly rare; I’ve seen warm surges up to the Pole in the dead of winter; last Christmas was the most recent example. )
This pattern is messing with my head, because all my pet theories are being trashed. For example, having “Ralph” at the Pole is indicative of a positive AO, which is suppose to have a more zonal jet around the Pole, not the loopy jet we’ve seen. A loopy jet is more indicative of a negative AO, as is the backwash bringing Siberian cold to Europe.
Looking at the above favorite-graphic-of-mine (lifted years ago from Joseph D’Aleo’s blog at the Weatherbell site) it seems Ralph is a hybrid and fits neither scheme. In some ways Ralph is like a Negative AO displaced to the east. Rather than the jet looping north to the west of Greenland we see the surge rush north to the east, and rather than the jet looping south again west of Scandinavia it comes south into Siberia. But the backwash is there, even if it doesn’t extend to England. Even though Ralph has made the AO officially positive, anyone in Central Europe would laugh and roll their eyes at the above graphic for a warm AO, which shows an arrow labeled “Mild” jabbing through Europe. The “Ice Age Now” site is full of stories of the amazing early winter clobbering Russia and Kazakhstan; ski areas in the Alps are opening three weeks early; and even way down in Sana’a, where the normal high temp is 25°C (77°F), instead the actual high temp recorded was 2°C (36°F). (You don’t know where Sana’a is? It is the capital of Yemen, in southwest Arabia, by the mouth of the Red Sea. Gosh, I thought everyone knew that!) Folk in Sana’a posted amazed pictures of snow in the hills around the capital (a bit blurry, I fear):
In order for the hybrid jet to revert to the above graphic of a “normal” negative AO, the current surge up past Svalbard into the Arctic Sea is going to sag all the way south until it heads due east through the Mediterranean. This crosses my eyes. For this to happen the surge will have to crash headlong into the current backwash even as a new backwash grows above it. (Don’t ask me to reconcile this discord. I’m just going to sit back, watch, and eat popcorn.) (And buy extra firewood.)
For the record, I should record that the current sea-ice extent is rising rapidly but still below normal.
Here is the NRL Concentration map. A lot of the gain has been in the East Siberian Sea, which is barely skimmed over. Also note ice isn’t all the way down the east coast of Greenland.
And here is the thickness map:
If the pattern flips and the AO goes negative, Kara Sea should skim over in a hurry. Hudson Bay often flash freezes, but we’ll have to wait and see how far west the jet is, if and when the pattern flips.
Don’t be surprised by surprises, but be surprised if you’re not surprised.
THURSDAY MORNING UPDATE
Both Ralph and Ralph’s secondary are heading up to the Pole with the surge of mild air, as Ralph’s tertiary stalls in their wake down by Britain. In the wake of this trio of storms a counter-surge of cold air is being swung south and east in the Atlantic, as the surge shifts east and warms Western Europe.
The temperature maps show the freezing isotherm never quite made it to the Pole, but the curl of Ralph’s signature is clearly seen even as Ralph weakens and fades, in terms of isobars. I have never seen such mildness up at the Pole this late in the autumn.
What I keep thinking is that the current pattern is a the worst possible investment of the planet’s heat. There is no sunshine at the Pole and all heat is being squandered to outer space. The stratosphere is at its lowest at the Pole, and even as we watch we can expect the mild temperatures to now crash a quick twenty degrees (and still be above normal) as all the surface heat rises to become occluded fronts and is largely lost. Heat that isn’t lost immediately to outer space will form clouds and snow, which releases latent heat during phase changes, both as the vapor condenses to water and as the water freezes to snow, and this heat is then also lost. (Any falling snow is a buffer against future heat, for, in the late spring, when the snow starts to melt in the midday sun, heat is sucked up in the process, becoming latent heat.)
We have no control over weather, but if we did a zonal flow would be a better way to budget the planetary heat, for the heat would stay further south and the Pole would become much colder. A bitterly cold Pole may look like the planet is colder in the short term, but cold air can’t lose heat it doesn’t have. In a zonal pattern some heat is lost through the sea-ice from the Arctic Sea, but the current pattern is losing a lot more heat from lower latitudes, sucking north heat from the Atlantic and, to a lesser degree, from the Pacific.
Nor does the current mild Pole make it milder to the south. Between now and mid-February subarctic regions are able to create their own cold, (or, more correctly, to lose their own heat), and the arctic is not necessary, as a “source region”. In fact the East Siberian tundra is usually colder than the Arctic Sea, whether the pattern is zonal or loopy (meridional).
What really makes it colder to the south is the spread of the snow-cover. During the next 70 days, when the sun is at its lowest and weakest, and days are at their shortest, the sun needs help to warm the air, and a dark surface helps absorb the wan light, but fresh snow-cover reflects the light. As soon as an area has snow daytime highs drop noticeably, and nighttime lows plunge, especially when the sky is cloudless and radiational cooling can occur.
Even with the current Pole quite mild we have seen record cold in Eurasia. Hopefully I’ll be able to update later about how the same may evolve in North America.
FRIDAY MORNING UPDATE
The spread of the snow-cover does not require below-average temperatures, in areas where the average is below freezing. Then, once the snow is laid down, above-average temperatures can become below-average simply by sliding south. For example, air may be well above-normal at -10°C (+14°F) when it up on the north coast of Canada, but if that same air slides south over snow-cover, gaining no heat (and perhaps losing some in the long nights and short, dim days), then you have -10°C (+14°F) pouring into the USA, where it is below normal. In terms of temperature anomaly maps, air that showed as cherry red becomes deep blue, even though it has remained the same temperature. All it needs do is slide south, which it indeed does, when the flow is loopy (meridional). Lastly, the snow-cover tends to form on the north side of the existing storm track, and, by intensifying the cold to the north, it tends to nudge the storm track south, so that the next storm lays down the next stripe of snow further south. (Not that warm air can’t move north over snow, but this requires a changed storm track.)
In conclusion, an expanded and above-average snow-cover increases the cold to the south, and decreases the absorption of heat to the south. It is the second wham of a double whammy. First, the cherry red anomaly at the Pole shows heat lost in the midday starshine of the northern night, and the blue anomaly to the south shows heat lost where there is sunshine. None of this is a sign the northern hemisphere is being particularly frugal with its supply of heat. Nor is it auspicious for those seeking a sign of a mild winter.
Our maps show Ralph once again fading at the Pole, as Ralph’s tertiary becomes a more typical North Atlantic low stalled off the coast of Norway. The “surge” has moved inland in Europe, and is crashing against the cold and intense high pressure of the Siberian “backwash”. An interesting new importer of mild air is developing through Bering Strait, on the Pacific side.
A quick glance at Dr. Ryan Maue’s excellent maps over at the Weatherbell site (week free trial offered there) shows the surge does not become a spear that thrusts the breadth of Eurasia, as happened other years, but rather gets squeezed.
The current GFS pressure-and-wind map shows a rush of colder air sweeping behind the various Ralphs, down from Iceland and then east towards Britain, bringing them a cold front and ending their time in the mild surge.
In three days the pressure anomaly map shows the high pressure remains stalled over Western Russia, as the tertiary of Ralph stalls, loop-de-loops northeast of Iceland, and develops a secondary of its own (Ralph the 4th) in the North Sea, and a tertiary (Ralph the 5th) off the northwest tip of Spain.
In five days the temperature anomaly map shows the “surge” now sandwiched between cold to the west and cold to the east. It will be interesting to see where snow-cover retreats and where it advances.
Over in North America yet another mild blob of air is being surged north to mellow the north, but our bank account looks like it is getting low. The first map shows it is currently above normal in the center of the USA, and the second map shows that in two days it will be well below, as the loopy pattern brings Canadian air south.
In the second map I’m still tucked in that small pocket of above-normal, in the very northeast of the USA, but the writing is on the wall: Winter is relentlessly advancing.