ARCTIC SEA-ICE –May Gale Blasts MOSAiC Expedition–

The past winter saw a surprising number of powerful lows cross Barents Sea into Kara Sea, with the north winds behind these gales pulling sea-ice south around Svalbard. The most recent gale took a more traditional route, hooking back west in a retrograde manner and passing right over Svalbard.

The MOSAiC Expedition, in the sea-ice about a third of the way to the Pole from Svalbard, experienced winds of 83 km/hr north of the gale, as the sea-ice accelerated from a nearly stationary drift to a drift  of over a kilometer an hour for a while. The bow-radar on the Polarstern showed a lead open and close, but not a great break-up of sea-ice. The sea-ice, which had been showing a slow drift southeast, was jerked west-southwest.

The MOSAiC Expedition, north of all the Barent Sea storms, has seen sea-ice in the Transpolar Drift move about twice as fast as usual. The hook to the southeast  was unusual, and perpendicular to the drift the Fram saw, New Years to Mayday, in 1896.

MOSAiC May 1 fsVIrgp

The recent jerk to the west-southwest is more in line with the Fram’s Track. It will be interesting to study the condition of the sea-ice, once the weather clears and the satellite view improves. Currently it looks like the gale tore the sea-ice from the north coast of Svalbard.

Svalbard May 13 Screenshot_2020-05-14 arctic io - Daily Satellite Images + Observations, 4-N90-E0(1)

What I wonder about is how much the sea-ice was compressed between Svalbard and the MOSAiC expedition. The Polarstern is suppose to head south towards Svalbard to be resupplied, and what they desire for such a journey is leads, and not pressure ridges.

There is an excellent video of part of the Russian icebreaker Kapitan Dranitsyn”s trip south from the MOSAiC site to port, showing how it has to back up and then ram to get through even ordinary sea-ice, yet has a far easier time once it finds leads skimmed with baby-ice.

In all, the journey of the Kapitan Dranitsyn from the MOSAiC site to port took three and a half weeks. The ship made it about halfway back to port in the thick sea-ice, and then was met by the Russian icebreaker Admiral Makarov, that refueled it. I think it took four days to complete the refueling. They then proceeded to the edge of the sea-ice in Barents Sea, but had to wait before venturing out into the open water because a gale was raging and the seas were too high. (I guess icebreakers are not designed for ocean storms.) They had to wait a week for the waves to subside under fifteen feet, but the MOSAiC scientists aboard got to observe how sea-ice fractures under the duress of huge swells. When the gale subsided they rushed across Barents Sea and two days later safely arrived in Tromso. (Likely some of the scientists had further adventures getting back to their home countries through the travel-bans of the Pandemic.)

It will be interesting to see what the Polarstern experiences, heading south.

The storm brought milder air over the arctic sea, including the year’s first patch of above-freezing air north of the Laptev Sea.

DMI meanT_2020 290513

The sea-ice “extent graph” shows the typical decline for this time of recent years:AAA DMI 020513 osisaf_nh_iceextent_daily_5years_en

Interestingly, the “volume” graph hasn’t fallen much, suggesting much of the sea-ice lost on the “extent” graph is baby-ice at the periphery, without much bulk to it.

DMI Volume 200513 Screenshot_2020-05-14 FullSize_CICE_combine_thick_SM_EN_20200513 png (PNG Image, 1337 × 1113 pixels)

Stay tuned.

 

 

ARCTIC SEA-ICE –Shift in the Drift–

Last post I talked about my yearning to see the Russian records of how the sea-ice drifted, in the cases of their 41 Arctic Ocean Bases, going all the way back to  1937, (as well as the 14 Barneo floating tourist-traps for the ober-wealthy, since 2002.).  Unfortunately such information is in some ways “top secret”, (in terms of industrial espionage, if not military). Because of this hidden record-keeping some shifts in the flow of sea-ice are described as “unprecedented” when in fact they have been seen before. The Russians themselves described two general flows of the sea-ice, translated as “circular” and “wash out”, yet the more political side of NOAA made a big deal of a change in the flow during the very-low-sea-ice year of 2012:

If that shift-in-the-drift was a sure sign of Global Warming, as certain Alarmists suggested when the above video was published in 2012, then surely the shift-in-the-drift away from that pattern to what we see now must refute Global Warming. Except it doesn’t. Alarmists either have very short attention spans, or have such overpowering confirmation-bias they’re blinded, or perhaps both.

The current drift is shown by the movement of the Polarstern and MOSAiC expedition, and is quite like the movement of Nansen’s ship “Fram” 130 years  earlier. (Blue line is the Fram after it was lodged in sea-ice).

https://upload.wikimedia.org/wikipedia/commons/thumb/e/ef/Nansen_Fram_Map.png/350px-Nansen_Fram_Map.png

This similarity is a little embarrassing for Alarmists, (especially when NOAA was stating currents had dramatically changed, only eight years ago). Fortunately for Alarmists, the Polarstern is moving much faster than the Fram did, and likely will cross a similar distance in perhaps only a third of the time it took the Fram. This can be used to suggest that the sea-ice is more “rotten” and that there is less of it, which may well be the case. (Although it may also be that the Polarstern is in the middle of the Transpolar Drift, while the Fram was closer to the Eurasian coast and may have been slowed by a counter-current which runs close to the coast.)

I tend to look about for other reasons the sea-ice may have been thicker in Nansen’s time. One thing that many have noticed is that the sun was “quieter” back then, if you look over the previous five decades. Nansen sailed the Fram at the end of sunspot cycle 13.

The very high sunspot totals (and low number of “spotless” days) of cycles 18 through 23 represent a time our Sun was quite energetic and pouring extra heat on the planet. Though we are now returning to quiet conditions, the arctic is currently still cooling from the warmer times which are called “The Modern Maximum”.  In Nansen’s day, however, the arctic was warming. In fact the high totals of “spotless days” before Nansen sailed are likely not as impressive as they look in the above graph, when you compare the above upward blip with the greater Dalton Minimum which preceded it, and the Dalton was preceded by the Maunder Minimum which is even more impressive. As measured by Carbon 14 in tree rings,  the energy of the “Modern Maximum” is especially impressive. (The graph below ends with the year 1950.)

I can’t help but wonder if Nansen and the Fram were sailing in an Arctic Ocean which “remembered” far colder times, whereas the MOSAiC scientists and the Polarstern are sailing in an Arctic Ocean which “remembers” warmer times, though those warmer times are now over.

Therefore I have a confirmation bias all my own. I am keeping a sharp look-out for changes which shift away from the lower ice-extents of the present to the higher extents of the past. For there can be little doubt the sun has gone quiet.

(Above from Joseph D’Leo’s blog on the Weatherbell Site.)

As my confirmation-bias looks for increases in sea-ice I often see the exact opposite of what I expect, because my thinking is too simplistic. Some of the ways the planet responds to a “quieter” sun are not what you would expect, and are counter-intuitive. Here are two I’ve mentioned in past posts:

First, you’d think less energy from the sun would make air colder and therefore drier, but instead the air gets warmer and moister, because the surface of the sea is warmer and more moisture evaporates. How can this be? I think this occurs because less energy from the sun also makes the winds less, and without strong Trade Winds the very cold waters can’t up-well along west-facing coasts as surface waters are blown off-shore. Therefore the first response to a “quiet” sun would be warmer seas (and El Ninos) and moister, milder air.  And Indeed the El Ninos have been strong and the La Ninos a bit feeble recently, and to this day the planet looks above normal at the equator.

https://www.ospo.noaa.gov/data/sst/anomaly/2020/anomnight.4.20.2020.gif

However such warmth draws upon the bank account of the past, robbing from Peter to pay Paul, and there are indications that, in the Pacific, it is superficial, and is currently being eroded away from below:

Only when the cold water reaches the surface and a La Nina occurs is my bias confirmed.

Second, one would think a “quiet” sun would immediately create more sea-ice in the Arctic Sea, but in terms of an important component it creates less.

The captains of icebreakers in the arctic keep a sharp lookout for “biggy bergs”, which are different from sea-ice of the same size and thickness. When an icebreaker nudges against typical sea-ice seven feet thick the sea-ice is a conglomerate, made of a multitude of thinner slabs, and the bow of the icebreaker finds it easy to break apart the many smaller slabs. However when a seven feet thick section of ice has broken from a glacier, it is rock solid, and the icebreaker gets quite a jar, meeting a “biggie berg”, even if the icebreaker doesn’t sink like the Titanic.

What is interesting about “biggy bergs” is that they are more common when the arctic is warming, and are few and far between when the arctic is cooling. And every Alarmist knows why: Warming causes glaciers to calve more. When times get colder the glaciers stop calving, and extend out to sea more, in some cases becoming shelves of ice.

During the “Modern Maximum” some of the big shelves created by the “Maunder Minimum” broke off, creating handy platforms for the spy-vs-spy bases of Americans (for example “Fletcher’s Ice Island”) and Russians  (for example the basement of their base “NP 22”, which was occupied more than eight years.) However, besides these large “ice islands”, which are few and far between, there are a great many “biggy bergs” deposited into the arctic ocean from glaciers that face north, and whose calving ice is not swept south in Baffin Bay or south along the east coast of Greenland, and instead bobs about in the Arctic Ocean along with more ordinary, conglomerated sea-ice, which is formed yearly by winter cold.

To me it seems “biggy bergs” must have an influence on both “volume” and “extent” of sea-ice, and it seems counter intuitive to me that the colder it gets the less they are seen (because north-facing glaciers cease calving them as it gets colder).

There is a third counter-intuitive thing happening I haven’t yet been able to put my finger on. All I know is that once again my confirmation bias has been sat backwards onto its butt. It has to do with how fast the Polarstern has been progressing across the Pole, and what this means in terms of Svalbard. With so much sea-ice rushing towards Fram Strait, by April 1 sea-ice surrounded Svalbard to levels I’ve never before seen.

https://realclimatescience.com/wp-content/uploads/2020/04/CICE_combine_thick_SM_EN_20200401.png

The build up of sea-ice around Svalbard is a little embarrassing for Alarmists, for a few years ago the situation was reversed, and south winds had pushed the sea-ice north of Svalbard even on its eastern side, which is relatively rare, and which Alarmists took to be a sign of Global Warming (and the doom of cute baby polar bears).  Now the sea-ice has returned with a vengeance, as have the highly adaptable bears (though hopefully the bears feel no vengeance).

Alarmists likely want to look away from Svalbard, but actually should take heart, for the “second lowest sea-ice extent evah”, in 2007, was achieved largely because a great deal of sea-ice was flushed south through Fram Stait. (Sea-ice south of Fram Strait is doomed to melt in southern waters).

(The site “Polar Bear Science” has a good post on the recent high sea-ice Svalbard situation here:)

Highest Svalbard sea ice since 1988 with Bear Island in the south surrounded

The problem with comparing the situation now with 2007 is that…well…it isn’t the same. That is what is troubling me, and I can’t quite put my finger upon.

Some things are similar: For example 2007 was also close to the minimum of a sunspot cycle, however 2007 was coming off a high maximum while we are now coming off one of the lowest maximums in the past 200 years. Also 2007 was at the heart of the “warm” AMO, while there are indicators suggesting we are now at the very end of the “warm” AMO.  Lastly, while Alarmists like to show decreasing sea-ice by starting their charts in the high sea-ice year of 1979, even their charts show things bottomed out around 2006-2007, and there has even been a slight rise, if you begin the “trend line” at that time rather than at 1979. For example, here is graph for extents in the month of March.

March 2020 average graph 1979-2020 NSIDC

You can’t help but notice the extent is now higher than 2006.

However what was most puzzling to me on April 1 was the sea-ice to the west of Svalbard. That should make any sea-ice geek quirk an eyebrow, for that area is nearly always free of sea-ice. That is where the Fram popped out into open water after crossing the Pole, 1893-1896, and that is where Willem Barentsz “discovered” Svalbard (Vikings likely were there earlier) in 1596. The water is usually open there because a northernmost tendril of the Gulf Stream, the West Spitsbergen Current, bounces off the coast of Norway and heads a little west of due north, entering the Arctic Sea on the east side of Fram Strait.  This current usually has a very impressive ability to melt sea-ice.  I have witnessed strong west winds push large masses of sea-ice across Fram Strait, and seen (in satellite photos) the entire mass of ice shrink and vanish in a few days. But this year hasn’t seen that. What the heck?

My guess is that the WSC (that is what we true geeks call the West Spitsbergen Current) has been cooled this year by the powerful storms we (last winter) saw not stall by Iceland (as is more ordinary) but remain huge into Barents Sea and even the Kara Sea. When such “Icelandic Lows” stay by Iceland, surges of mild air are brought north, sometimes all the way from the balmy Azores, on the storm’s east side. But, when the storms are displaced east, as they were this year, the same waters get north winds on the gale’s west side. This year we saw the waters that hold the WSC blasted by north winds gusting to hurricane force, with waves up to forty feet tall. Not only would this churn and chill the WSC, but it would physically transport the water at the very surface of the current in the wrong direction.

This moves us into an interesting topic, if you are a true geek, involving a sort of water budget.  It must be balanced. The water entering the Pole must be balanced by by water leaving the Pole. The WSC entering the Pole is more than matched by, on the far side of Fram Strait, the very cold EGC (East Greenland Current). More water leaves the Pole by sea than enters by sea, for evaporation is low due to sea-ice and cold temperatures, and much extra water enters via some of the world’s biggest rivers, as well as glaciers.

What is most fascinating is the fact various currents often (but not always) keep their identity as they travel around under the sea-ice. Water from the south tends to be saltier, but is made less salty as it melts sea-ice, yet can still be identified as a separate current.  Some currents dive beneath other currents, because the buoyancy of a current is determined by its salinity and its temperature, which are always changing. When waters are quiet, undisturbed by storms under ice, they can stratify into various layers, with each layer part of an identifiable current. Therefore the WSC, after passing through Fram Strait, forks into the Yerkmak and Svalbard branches, which can be traced all the way around the Pole until they exit as the RAC (Return Atlantic Current) which heads south in the middle of Fram Strait between the Colder and less salty  EGC heading south to the west and the milder and saltier WSC heading north to the east.

To make things either more interesting or more annoying, (depending on your temperament), is that, when you return the following year, things may have changed. For example, the WSC may have three other branches (perhaps more) besides the Yermak and Svalbard branches, but they are not seen every year.

In my humble opinion the study of such currents, and the way they change, is very important. Why? Because they set up certain areas of sea-surface-temperatures (such as the “warm blob” in the Pacific) which have been seen to have a major influence on the route taken by atmospheric jet-streams, which can determine things such as which-crops-are-wisest-to-plant-where.

One such change is the shift in the AMO from “warm” to “cold”, which we know little about because the last time it occurred satellites had barely been invented. It involves some major shifts-in-the-drifts which we will in many ways be seeing for the first time (by satellite, at least). The scant records we have from the past indicate the changes are major. For example, the prime fishing grounds for herring can shift hundreds of miles.

The above newspaper article from 1922 describes how swift and dramatic the change from a “cold” to “warm” AMO was around Svalbard, however it took more than a decade for the warming to start reaching the Russian coast and making the Northeast Passage more passable. (It was fortunate the sea-ice was still low when Hilter invaded Russia, for the British learned it was suicide to attempt to send Russia supplies via the arctic routes during the broad daylight of summer, and despite Stalin’s objections the British only dared do it in the darkness of arctic winter. Had sea-ice been more formidable then supplying Russia might have failed and Hitler might have succeeded.) But, to return to my point,  I assume the change back from “warm” to “cold” might also be swift and dramatic, and might also be first seen around Svalbard.

One major element of the shift-in-the-drift involves a simple fact: Cold water sinks. When the EGC brings cold water south along the east coast of Greenland it stays at the surface because the shallow continental shelf keeps it from sinking, and also to some degree by the fact less saline water is more bouyant than more-saline water, even if it is colder. However down around the latitude of Iceland the bottom falls, and so does much of the EGC.  In a manner that makes niagra falls look like a trickle, humongous amounts of cold water plunge to the ocean’s abyss, and seemingly such cold loses all ability to influence the surface.  But does it?

Allow me to subject you to a simple thought-experiment. Imagine a large box of water is plunged downwards. What will this do to waters at the surface, and what will this do to the waters beneath?

At the surface it is obvious that waters must rush in to replace the water that sinks. But what determines whether it will be warm water rushing up from the south, or cold water rushing down from the north?  History hints both have happened, and that what determines the flows of waters is as varied as what determines the flows of air on a surface weather map. But, on occasions when the flow of waters is increased from the north, the EGC transports south cold water that refuses to sink, called sea-ice. This sea-ice at the surface can change the temperature of sea-surface water hundreds of miles further to the south, changing air temperatures and the weather of lands downwind, and also causing more waters to chill and sink.

Beneath the sinking cold waters is the abyss, which we know little about. However we do know water can’t compress, and when water presses down from above the water beneath must move to make room. Some of this movement is explained by deep sea currents. However such currents are very slow, nor do they vary much. When a charge of bitter cold arctic air causes much more cold water to sink, the deep sea currents don’t speed up, (as far as I know, at this time.)  Therefore things are not adding up. When water presses down from above room must be made for it, but where is the room made?

Two ideas have occurred to me. One idea is that room is made by bulging the thermocline upwards, but this bulge would become a sort of wave moving away through the thermocline like the ripple from a splash, an undersea phenomenon which as far as I know is undocumented, but which, if it did exist, would have some effect when the wave hit a distant coast. A second idea is that, just as when you push a brake pedal an immediate effect is seen in rear brakes far from the actual pedal, when cold waters sink south of Fram Strait, an immediate up-welling effect might be seen in some place far away, because water can’t be compressed. I am well aware this second idea is outlandish, but is it as outlandish as this: (?)

Patient, hard-working scientists have mapped the slow currents of the abyss, and to some degree have mapped the undersea rivers which connect where waters sink and where up-welling brings deep waters back up. Yet none of these rivers ends at the biggest up-welling, off the coast of Peru, which is part and parcel of the switch from El Nino to La Nina.

Thermohaline circulation - Energy Education

Only recently have maps started to include a branch of the thermohaline circulation past the coast of Peru, but this shows a warm surface current and not the cold up-welling so vital to the creation of La Nina’s (and to the fisheries of Peru.)

https://i0.wp.com/blogs.evergreen.edu/seachange/files/2013/05/AlyssaConveyor2.jpg

 

The generally accepted idea is that the up-welling off the coast of Peru is caused by strong offshore Trade Winds blowing from South America westward into the Pacific. These winds blow the warm surface water towards Australia, which causes cold, nutrient-filled waters to be drawn up from the depths to replace the displaced surface water.  The problem with the idea is that the up-welling has a degree of independence from the wind. At times the up-welling can even occur before the increase in the Trade Winds, in which case the colder water appears to be causing the increase as much as the increase causing the colder waters. This has two effects. First, it makes El Ninos and La Ninas notoriously hard to forecast, and second, it allows madmen like myself to suggest that pushing water down in Fram Strait can cause water to up-well off the coast of Peru.

In any case the shift-in-the-drift off the coast of Peru has major repercussions, in terms of the world’s weather, just as the shift-in-the-drift in the North Atlantic associated with the switch of the AMO from “warm” to “cold” has major repercussions, in terms of the world’s weather. Such major repercussions are interconnected in ways we do not yet understand. Inquiring minds want to know. Scientists state “further study is needed”, holding out a cupped palm for money.

In my opinion the late Bill Gray’s desire for funding to better understand thermohaline circulation was intuitive genius, while Al Gore’s petty prevention of such funding was the initial travesty which has seen Global Warming politics befoul science. Money which could have been wisely used to further our understanding has been redirected to political hacks. Things important to study have been neglected to study the incidental. Not that I have anything against the study of polar bears, but bears can’t determine which crops to plant in Kansas, while the shift-in-the-drift can.

In order to redirect funding in unproductive ways, politicians always seem to need to invent a crisis, whether it be acid rain, or ozone holes, or global warming, or a corona virus pandemic. The problem is that when you are too unproductive you wind up broke.

End Rant.

In any case it will be interesting to watch the sea-ice in the North Atlantic as the winter gales die down and the quieter summer weather arrives. For five years now the two long-term measuring points of the Norwegan Current, which feeds into Barents Sea, have been noting a decline in water temperatures:

Sea-ice extent is within two standard deviations from normal, and high for recent years, though still low.

DMI 200424 osisaf_nh_iceextent_daily_5years_en

Both the Kara and Laptev Seas have seen a lot of sea-ice exported north into the Central Arctic this winter, and thin baby-ice now skims them, so I expect a fair amount of Alarmist hoop-la to occur when they become ice-free this summer. This may be reflected in a plunge in the extent graph, as they melt. However the hoopla may then die down as the extent graph flattens, as other parts of the Arctic Ocean see sea-ice more stubborn. If the PDO remains in its “cold” phase it will be especially interesting to see if sea-ice remains stubborn north of Bering Strait.

The “volume” graph is currently very low for this time of year, likely due to the thin ice in the Laptev and Kara Seas, and also due to an incapacity inherent in measuring the volume of pressure ridges, which are numerous in the Central Arctic due to all the sea-ice transported north from the Kara and Laptev Seas. I expect the “volume” graphs to become more normal later in the summer, when pressure ridges tend to crumble and spread out, and be included more easily in the totals.

The MOSAiC expedition is now experiencing 24 hour daylight, and I am enjoying the pictures I crave, which have been sorely missed since the camera-buoys stopped being funded. The scientists are enjoying the one part of the world without corona virus, and witnessing first hand how very dynamic the sea-ice is. A large lead snapped the cables powering one of their remote station, forcing them to operate at a reduced capacity with generators for around three weeks until they were able to lay a new cable.

MOSAiC lead Screenshot_2020-04-23 MOSAiC(1)

Other leads have opened and crushed shut again, forming pressure ridges.

MOSAiC Pressure ridge 4-20 Screenshot_2020-04-23 MOSAiC(2)

MOSAiC Pressure Ridge 4-16 Screenshot_2020-04-23 MOSAiC

Some of the things they are studying are fascinating, such as the biology under the ice. Other studies seem based on the Global Warming narrative, and make me want to roll my eyes. (I will bite my tongue, regarding measuring the nearly non-existant amounts of nitrous oxide exuded by the Arctic Ocean.) (Of course, data is data, and when I was young I would have counted the number of leaves on a tree, if it let me avoid getting a Real Job.)

What really interests me is the shift-in-the-drift, but things do get more tranquil in the summer, and the currents slow down. (The WSC north through Fram Strait nearly halts at times.) While the Polarstern had been making steady progress towards Fram Strait, it recently experienced a bit of “wrong way” drift.

MOSAIC wrong way Screenshot_2020-04-23 MOSAiC(3)

 

This expedition is experiencing some interesting resupply problems they are not talking about, due to the rest of the world going crazy due to the Corona Virus. If they dawdle too much, getting down to Fram Strait, their story could get interesting.

Stay tuned.

ARCTIC SEA ICE –Icebreaker Trapped Resupplying MOASiC–

In my last post I mentioned that the Russian icebreaker  Kapitan Dranitsyn had to battle thick sea-ice to resupply the Polarstern at the MOSAiC site. Contact was successful, and cranes began to  unload and load supplies that were hauled by tractor between the two ships.

PS1 polarstern-1-e1583402517868

A fresh crew of scientists relieved the crew that has been working there.

PS2 polarstern-unloading-2-credit-michael-gutsche

With temperatures down around -30ºC, the open water in the wake of the Kapitan Dranitsyn froze over swiftly. Men could walk on the new ice within 24 hours.

PS3 polarstern-and-icebreaker.1f7f58

By the time the transfer of men and supplies was complete the ship was frozen so fast it could not extract itself. The news is now that the Russians are sending a second icebreaker, the Admiral Makarov, to help the first icebreaker free itself. (Note the twilight in the above picture. The are located close enough to the Pole to see a very swift transition from noontime night to midnight day. Currently it is dark at midnight, but the twilight is bright enough at noon to read by. In around a week the sun will peek over the horizon, and a few weeks more will see the daylight become constant. But the chilly sun remains so low that no thawing occurs until the end of April.)

Despite the ice trapping the icebreaker, it is important to remember we are talking about sea-ice, a mass of ice in constant motion with enough “leads” (cracks) to allow seals to breathe and be seen hunting arctic cod, by the MOSAiC underwater cameras. Sea-ice is by no means stable. The Polarstern radar recently saw a lead open roughly a mile from the ship.

And the infrared view of the Pole shows plenty of cracks in the sea-ice,

.PS4 go.nasa.gov2TJSpHR-shears-

In other words, sea-ice is not the same thing as the gigantic icebergs that make life interesting for fishermen in Newfoundland, icebergs that are so vast that they can run aground in water 300 feet deep.

Newfoundland Icebergs view-of-twillingate-harbour

Newfoundland Iceberg u41bdg57z4k41

These giant, awesome bergs calve off glaciers, (largely Greenland’s), and, while they have been seen in the Arctic Ocean, they usually head south down either side of Greenland, and are rare up north. For the most part the sea-ice affecting the icebreakers is thin in comparison, roughly six feet thick.

The problem is that, besides cracking apart, which is helpful to icebreakers, the ice claps back together again. In such cases the baby-ice which swiftly forms in the open water, (as we saw in the wake of the Kapitan Dranitsyn), has little hope of resisting the compression it undergoes; even if it is two feet thick it is clamped in the jaws of ice at least three times as thick, which has the power of wind pressing across miles and miles of fetch. Consequently the new ice in leads crumples up like eggshells between elephants, and what was open water on Monday may become a pressure ridge of crumbled slabs of ice by Friday. And, because this process goes on all winter long, the surface of the Arctic Sea is far from smooth. There are smooth areas, basically big slabs, but finding a smooth area large enough for the yearly Barneo blue-ice airstrip often involves a considerable search.

Considering the sea-ice is constantly tortured and contorted, the “thickness” maps portray an average, for in fact the ice can vary between open water and a towering pressure ridge in a hundred yards. (This was made visual back in the days we had cameras on buoys bobbing about the Pole.) Because both pressure ridges and leads are often too narrow to be seen by satellite, and also because how numerous they are varies a lot between stormy years and calm years, a certain amount of guess-work (also called “modelling”) goes into the creation of “thickness” maps…..which in turn leads to disagreements. For example the NRL map can show ice six feet thick

Thickness 200303 arcticictnnowcast

Whereas the DMI map shows sea-ice twelve feet thick:

Thickness 200305 CICE_combine_thick_SM_EN_20200305

These disagreements suggest the captains of icebreakers face uncertainty, as they face the sea-ice.  Not only are the captain’s initial maps to some degree “modeled”, but the circumstances they are sailing into are in constant flux. Though their radar may show an open lead ahead, a shift in the winds may turn that lead into a pressure ridge in a mere hour.

One then is led to wonder why these icebreakers are not ever crushed like a nut in a nutcracker. The compression involved when wind-shear creates two masses of sea-ice converging is hard to imagine. We are talking about fifty miles of ice colliding headlong with fifty miles of ice; even sea-ice nine feet thick can buckle, creating the arctic’s biggest pressure ridges, thirty feet high and (because nine tenths of an iceberg is under water) with “keels” extending downwards 270 feet. A 1880’s ship like the Jeanette, with a greatly reinforced hull, might survive 21 months clamped in sea-ice, but it stood little chance when the sea-ice concentrated its squeeze. (Descriptions of the moaning noise the Jeanette made as it went down are amazing.) Therefore men learned to structure hulls in a manner that caused squeezing from the side to lift the ships upward, rather than crushing inward. Icebreakers utilize such uplift, as the entire ship rides up and over the ice, which is then crushed down and broken by the sheer weight of the ship.

The Russian icebreakers are huge. The Kapitan Dranitsyn has seven stories of windows above the main deck. Let’s look at the picture again:

PS3 polarstern-and-icebreaker.1f7f58

Besides riding up over the ice moving forward, such ships are designed to ride over ice when moving astern. When the ice is especially thick they can back up and plow forward repetitively, crunching the ice downwards and making their way to where radar indicates a lead may provide an easier path.

The fact Kapitan Dranitsyn requires help indicates, to me at least, that the sea-ice is especially thick in the Central Arctic this year.

Stay tuned.