The 2022/2023 freezing season

[Freegrass]

I think it's time to call it.

Here's the 365 day HYCOM gif to start off a new season.
Very Large Gif!

[oren]

Thanks. I prefer to wait another day or two for the switchover, the thread can remain but not stickied.

[oren]

On to freezing. The very useful AWI SIC-Leads animation shows freezing of the previously-open water near the Pole, and in the CAB sections facing the Chukchi, the New Siberian islands and Severnaya Zemliya. The Greenand Sea also appears to be solidifying.
Elsewhere, Lincoln sea ice still flowing down the Nares but is no longer melting out immediately, and the CAA sort-of Garlic Press continuing but exported ice is slowly taking a foothold in previously open water.
Meanwhile, southern Beaufort still seems weak and southern ESS still somewhat melting.
DMI N of 80 chart shows the temperature drop that's behind the freezing in the central CAB.

[Aluminium]

September 16-20.

2021.

[Jim Hunt]

Meanwhile I'm still intrigued to see what effect ex Typhoon Merbok has on the sea ice in the ESS:

https://GreatWhiteCon.info/2022/09/facts-about-the-arctic-in-september-2022/#Sep-18

However the refreeze north of Chukchi/Beaufort is very evident in this close up animation!

[Click to enlarge/animate]

[Freegrass]

Latest Five Day Forecast + Last 48h
Wind + Temp @ Surface
Large GiF!

It looks like the Gyre is getting fired up early this year with a turbo boost... Not sure how the ice will react to this, other then that the last of the MYI will start to move towards the Beaufort sea already.

[Phil.]

Looks like the remains of Hurricane Fiona will be traveling up Baffin Bay early next week which could be interesting.

[Aluminium]

September 18-22.

2021.

[Freegrass]

Latest Five Day Forecast + Last 48h
Wind + Temp @ Surface
Large GiF!

I added the 30 day HYCOM, which shows how the MYI is moving towards to Beaufort sea with this strong wind. There it'll have a bigger chance to get caught into the Beaufort gyre during winter, giving us a similar situation like we had in 2020/21 with the flute playing mouse...

Curious to see if that tick ice in the Lincoln sea will be able to block the Nares strait this winter.

[Aluminium]

September 20-24.

2021.

[oren]

Latest Five Day Forecast + Last 48h
Wind + Temp @ Surface
Large GiF!

I added the 30 day HYCOM, which shows how the MYI is moving towards to Beaufort sea with this strong wind. There it'll have a bigger chance to get caught into the Beaufort gyre during winter, giving us a similar situation like we had in 2020/21 with the flute playing mouse...

Curious to see if that tick ice in the Lincoln sea will be able to block the Nares strait this winter.

Unfortunately that thick ice does not exist in the Lincoln, and is a model artifact, IMO. Lincoln has been exporting down the Nares all year, and the remaining Greenland ex-fast ice is about to wash down the strait as we speak. The Nares is hard to model due to its narrow width and the typical coarseness of grid resolutions.

[Glen Koehler]

     Does the opening of the GL megacrack (lifting of land-fast ice from shore) increase Nares export?

[Niall Dollard]

NOAA ESRL initial and then 5 day forecast image indicating that the older "pink" thick ice (>1.6m thick) is sliding down towards the Beaufort. Likely to melt there next summer as the Beaufort is no longer capable of retaining old ice.

Click to run

[oren]

AWI SIC-Leads animation.

Every week I post this and stare at the Lincoln-Nares export machine. It's been going on nonstop.

[Freegrass]

AWI SIC-Leads animation.

Every week I post this and stare at the Lincoln-Nares export machine. It's been going on nonstop.

I love these animations Oren, and the movement of the thick MYI towards the beaufort sea is clearly visible now. Later on in the freezing season, that ice will have a lot less freedom to move as it's being pinned against the coast by the rest of the ice pack. So the distance it moves right now matters.

Nares transport is indeed making it unlikely that there's thick ice in the Lincoln sea like HYCOM is showing.

[morganism]

Weather: An early disruption event is starting for the Polar Vortex, with pressure anomalies setting the stage for something bigger later in Winter

https://www.severe-weather.eu/global-weather/polar-vortex-early-disruptive-event-winter-influence-united-states-europe-fa/

"But besides directly affecting the Polar Vortex, the pressure anomalies in the next days/weeks will also put another process in motion that can be even more disruptive for the Winter polar circulation. You will see how having more snow in October can mean more snow and cold in the Winter."

[baltic dweller]

A fresh satellite photo of the Vil'kitsky Strait. Would this be considered officially the closing of the Northeast Passage this year?

[Aluminium]

September 22-28.

2021.

[phelan]

Looks from Aluminium's animation like the Northern Sea Route is just about to close, if it hasn't already.  Is it that happening a bit earlier this year compared to recent years?

EDIT - I'm sorry Baltic Dweller, I scrolled up to check and still missed your post.  Thanks for the detailed image...

[oren]

A fresh satellite photo of the Vil'kitsky Strait. Would this be considered officially the closing of the Northeast Passage this year?

Welcome, baltic dweller. The first post is the hardest...

As you can see the same issue was raised by phelan.

[Jim Hunt]

Looks from Aluminium's animation like the Northern Sea Route is just about to close, if it hasn't already.

It's not quite there yet:

https://GreatWhiteCon.info/2022/06/the-northern-sea-route-in-2022/#Sep-29

IMHO!

P.S. Sorry Baltic Dweller - I just scrolled up again!

[Aluminium]

September 26-30.

September 1-30 (fast).

2021.

[uniquorn]

GFS forecasting a 960hPa low over north Chukchi on friday with 70km/h southerly near Barrow Canyon.

https://stratobserve.com/misc_vort3d

windy ecmwf a little earlier at 961hPa

[baltic dweller]

Could we call it now, Jim? The green pixel adjacent to the Taymyr Peninsula coast, according to the NASA Worldview tool, is at 62% sea ice concentration according to the AMSR2 sensor.

[nadir]

GFS forecasting a 960hPa low over north Chukchi on friday with 70km/h southerly near Barrow Canyon.

https://stratobserve.com/misc_vort3d

Expect 5m waves and a lot of ocean heat pumping up to the ocean surface.
This can contribute to late Chukchi refreeze but I am not sure it is bad for ice. Very strong storm over open ocean extracts a lot of heat that had entered via Bering Strait -> heat will be vented out during the Arctic autumn even before the ocean refreezes.

[uniquorn]

GFS forecasting a 960hPa low over north Chukchi on friday with 70km/h southerly near Barrow Canyon.

https://stratobserve.com/misc_vort3d

Expect 5m waves and a lot of ocean heat pumping up to the ocean surface.
This can contribute to late Chukchi refreeze but I am not sure it is bad for ice. Very strong storm over open ocean extracts a lot of heat that had entered via Bering Strait -> heat will be vented out during the Arctic autumn even before the ocean refreezes.

I was thinking more about eddy formation in the Barrow Canyon but will there be much ocean cooling this early in the season with southerly winds and air temps between -3C and +3C?

[nadir]

GFS forecasting a 960hPa low over north Chukchi on friday with 70km/h southerly near Barrow Canyon.

https://stratobserve.com/misc_vort3d

Expect 5m waves and a lot of ocean heat pumping up to the ocean surface.
This can contribute to late Chukchi refreeze but I am not sure it is bad for ice. Very strong storm over open ocean extracts a lot of heat that had entered via Bering Strait -> heat will be vented out during the Arctic autumn even before the ocean refreezes.

I was thinking more about eddy formation in the Barrow Canyon but will there be much ocean cooling this early in the season with southerly winds and air temps between -3C and +3C?

Eddy formation that could lead to trapped heat being transported very long distances and affecting the ice is what you’re up to? (Sorry, just that I am not following…).

Also the previous point I did is not very clear. Yes this strong low will pull heat from the ocean to the atmosphere (and from there to space) before refreeze, but in absence of the low, most of this ocean heat from the Pacific would get buried in the Pacific halocline wouldn’t it?

So it’s like the heat goes away to space or it gets buried. In any case, during Fall, when Arctic amplification is most evident because most heat is released also represents a negative feedback because the heat is lost either in space or sufficiently deep into the ocean.

The initial refreeze is the most difficult stage to understand imo.

[uniquorn]

Warmest parts of Chukchi are at 8C so there will be some cooling. Here is the cmems forecast for the Barrow Canyon area predicting a 6C westward eastward flow down the Alaskan coast into the Beaufort and warmer water downwelling into the Canyon and beyond to 100m depth.
https://myocean.marine.copernicus.eu/-/7xqpw3dyum

-------------------------------------

For further reading, this paper may apply to the upcoming forecast.

Shelfbreak Downwelling in the Alaskan Beaufort Sea
Nicholas P. Foukal, Robert S. Pickart, G. W. K. Moore, Peigen Lin
First published: 16 October 2019   https://doi.org/10.1029/2019JC015520

Abstract

The oceanographic response and atmospheric forcing associated with downwelling along the Alaskan Beaufort Sea shelf/slope is described using mooring data collected from August 2002 to September 2004, along with meteorological time series, satellite data, and reanalysis fields. In total, 55 downwelling events are identified with peak occurrence in July and August.

Downwelling is initiated by cyclonic low-pressure systems displacing the Beaufort High and driving westerly winds over the region. The shelfbreak jet responds by accelerating to the east, followed by a depression of isopycnals along the outer shelf and slope. The storms last 3.25 ± 1.80 days, at which point conditions relax toward their mean state. To determine the effect of sea ice on the oceanographic response, the storms are classified into four ice seasons: open water, partial ice, full ice, and fast ice (immobile). For a given wind strength, the largest response occurs during partial ice cover, while the most subdued response occurs in the fast ice season.

 Over the two-year study period, the winds were strongest during the open water season; thus, the shelfbreak jet intensified the most during this period and the cross-stream Ekman flow was largest. During downwelling, the cold water fluxed off the shelf ventilates the upper halocline of the Canada Basin. The storms approach the Beaufort Sea along three distinct pathways: a northerly route from the high Arctic, a westerly route from northern Siberia, and a southerly route from south of Bering Strait. Differences in the vertical structure of the storms are presented as well.

[Jim Hunt]

Could we call it now, Jim?

It would be nice to have confirmation by Sentinel 1, but I reckon so:

[El Cid]

Warmest parts of Chukchi are at 8C so there will be some cooling. Here is the cmems forecast for the Barrow Canyon area predicting a 6C westward flow down the Alaskan coast into the Beaufort and warmer water downwelling into the Canyon and beyond to 100m depth.

On the spot study!

I wanted to write something similar but was not at all sure about it. My reasoning was that currently the Chukchi is very warm, so a big disturbance by wind is more likely to push these warm waters down and bring cold water up, so in my mind a storm like this was more likely to initiate surface cooling (and warming deeper waters). Thank you for the confirmation!

[Niall Dollard]

Two recent tweets by Rick Thoman on the current Chukchi storm and the effect of ex Merbok on Bering SSTs.

[Eco-Author]

From Rick Thoman's Tweet above: "Recent storminess... has mixed warmer waters on top with cooler water at depth, reducing departures" I feel that most any storm, not to mention one as strong as this one, serve to SAVE the heat gained in the summer by mixing it deeper.... Even if the SSTs fall, the heat is still there as a whole and being mixed deeper will not be given up before the ice forms to trap it in!  You can say a similar thing for Kara/Barrents... The storm on the Atlantic side is near as impressive and seems to last a long time thus itself greatly increasing export!  Seems like export through CAA may also jump?! 

[Aluminium]

September 28 - October 4.

2021.

[uniquorn]

GFS forecast for N Chuckchi storm now dropping to 956hPa.

Barents forecast for 966hPa. Latest from float 690375 in the northern Barents was oct2 so should be due another soon. Water in that area is already well mixed down to 40m at 2.285C. Closer to 4C from buoys further south
https://fleetmonitoring.euro-argo.eu/float/6903705

[Jim Hunt]

I reckon so:

However today I have changed my humble opinion:

https://go.nasa.gov/3V1PuJo

[nadir]

A swell of amplitude 5m is predicted in the wake of the strong Chukchi low.
Wave height (swell from storm 100s miles away from the edge+wind waves) will exceed 6m. Will be interesting to see the temporary effect on the refreezing pack.

[Jim Hunt]

A swell of amplitude 5m is predicted

Here's the long distance swell disaggregated from the wind waves:

https://GreatWhiteCon.info/2022/10/facts-about-the-arctic-in-october-2022/#Oct-06

[Aluminium]

957 mb. At this time of year, snow cover may insulate the ice for the rest of season, reducing growth rate.

[Eco-Author]

I'm wondering could it be argued that this storm will ultimately have just as bad if not worse effect on the arctic - long term - than a GAC in Aug.  ANY MIXING is SUPER BAD and maybe even worse than lower extent numbers one year.  I'd have to assume that the mixing is even more extensive over open water than over ice?!? 

[uniquorn]

WHOI TOP7 was deployed in open water on oct1. It's the nearest itp to the low pressure event.
Drift speed increased significantly and there is some mixing, mostly upwards imo.
https://www2.whoi.edu/site/itp/data/active-systems/top-07/

[uniquorn]

Could be related to what looks like an warm old eddy at 50m, max 2.2C

year   day            dbar   temp(C)  salinity
2022  280.03565   44    1.9863   31.3758
2022  280.03592   45    2.1986   31.4071
2022  280.03538   46    2.1884   31.4355
2022  280.03537   47    2.1315   31.4331
2022  280.03565   48    2.0143   31.4347
2022  280.03565   49    1.9630   31.4420
2022  280.03756   50    1.9374   31.4749

[nadir]

Could be related to what looks like an warm old eddy at 50m, max 2.2C

year   day            dbar   temp(C)  salinity
2022  280.03565   44    1.9863   31.3758
2022  280.03592   45    2.1986   31.4071
2022  280.03538   46    2.1884   31.4355
2022  280.03537   47    2.1315   31.4331
2022  280.03565   48    2.0143   31.4347
2022  280.03565   49    1.9630   31.4420
2022  280.03756   50    1.9374   31.4749

That’s interesting. When you say old you mean it is not caused by any recent event? And you know it’s  old because it only shows at 50m depth?

Please feel free to answer at a different thread (or not answer). Thx

[uniquorn]

When you say old you mean it is not caused by any recent event?

Yes. The mixing to surface is probably related to the recent low pressure event but 2.2C water at 50m is probably pacific summer water. As modelled by Mercator its main entry points to the Beaufort are near Barrow Canyon where it is warmest and north of the Northwind Ridge as shown in the high contrast 34m temperature image.
Ocean gyre circulation suggests BC for TOP7 location.

[uniquorn]

Some effect on the western Beaufort yesterday

[uniquorn]

More buoy detail from whoi top7.

1. Temp 1-200m depth, buoy has drifted beyond the eddy. 2 of the deeper profiles were incomplete, probably due to high drift speed.

2. Temp 1-20m, mixing to surface event has subsided. Will have to look at other buoys for evidence it is widespread. The sic-leads ani suggests it is.

3. Salinity 1-20m, mixing to surface event has subsided leaving lower salinity in the top 20m, suggesting melt.

4. rawmat pressure with temp and salinity, 0.55dbar-1.21dbar. I don't pretend to fully understand this yet but find it interesting and post in case it helps others.
not adjusted for local pressure changes

[Lord M Vader]

According to NWS Alaska, the intensive cyclone in Chukchi is at or near record strength.

https://mobile.twitter.com/NWSAlaska/status/1578151249173970945

"The @NWSOPC has analyzed a 955mb low pressure in the Chukchi Sea. This value is at or near a record intensity for this location, with records going back to 1950."

[uniquorn]

polarview S1A with contrast adjustment, interesting to see how long refreeze takes.

[be cause]

A worldview winter view of Lincoln and Nares ..
                                                                 https://go.nasa.gov/3fWeYYJ

[uniquorn]

Beaufort update from awi sic-leads v110

whoi top7 drift and rough location on yesterdays aqua modis (light contrast)

https://go.nasa.gov/3fIrSsW
https://www2.whoi.edu/site/itp/data/active-systems/top-07/

[oren]

An AMSR2 animation of sea ice concentration in the central Arctic, courtesy of the Alfred Wegener institute (AWI). Note the Leads experimental product exaggerates the width of leads, in order to better show movement. More information available in the AWI thread mostly updated by uniquorn.
Click to animate and click again for maximum resolution.
Source is mirrored on https://seaice.de/AMSR2_Central_Arctic_SIC-LEADS.gif