Snow and Ice Northern Hemisphere - Winter 23 /24

[WYorksWeather]

 Midlands Ice Age Didn't intend to imply otherwise!

You do a great job maintaining this thread, despite the fact that we don't hold the same views on AGW.

 

[Methuselah]

 WYorksWeather I agree. 

[Midlands Ice Age]

13 minutes ago, WYorksWeather said:

Didn't intend to imply otherwise!

You do a great job maintaining this thread, despite the fact that we don't hold the same views on AGW.

I hold exactly the same views as yourself on AGW....  However,  I have not totally ignored that other drivers have not suddenly all disappeared  and are still present in worldwide climate change. My mind is still open as to the various impacts of all competing mechanisms. 

MIA

[Methuselah]

 Midlands Ice Age Aye, MIA; there are so many feedbacks that no one knows the truth.

[WYorksWeather]

 Midlands Ice Age

Interesting - I thought you thought the changes in global temperature were primarily natural in origin (unless I'm confusing you with someone else?). Probably best not to discuss here in any case as I don't wish to derail your thread any further.

To bring things back to the sea ice data, I grabbed the NSIDC raw data for January extent and did some calculations.

The furthest year you can go back to and find a positive trend is 2010 (i.e. testing 2020-2024, 2019-2024, etc., and looking for the earliest year where the regression coefficient is positive).

That means we're at 15 years,  which is similar to the trend I mentioned for global surface temperatures, for which you could at one stage I believe select 1998-2012 or so and find no trend. This is of course cherry-picking and not scientifically valid in any way, but just to illustrate the concept of what I've done here.

Of course, we all know what then happened in 2015 and 2016 with global temperatures, and of course more recently 2023 and 2024. So, the key I believe will be whether we see our 2016 analogue in the next few years.  The last very substantial step change was from around 2003-2005 for January extent, since which no year has exceeded 14m km^2, and the one before that in the early 1980s, since which no year has exceeded 15m km^2. If this does run on some sort of approximate 20-year cycle, then you'd expect another step change at some point in the 2020s.

Coincidentally, the Pacific Decadal Oscillation has a period of 20-30 years, so that might be my first proposed culprit for natural variability on these inter-decadal cycles. In other words, we have a fairly steady declining trend, but the PDO interacts with this to create the illusion of periods of stability followed by sharp declines. Just a hypothesis, and I don't have any real evidence to back it up beyond just statistical correlation.

 

 

[Midlands Ice Age]

 WYorksWeather

There is a known problem with the NSIDC data. That is that it uses a  fixed 'mesh grill' for its coastal sea ice definitions.

That is the reason that the ASIF switched to use Jaxa for its main data analysis source.

Masie is the most accurate for day to day data as it is used by the US navy for its ocean surface transportation data..

That is why I use Masie!!.

It is not a climate dataset so no historical comparison for the further past (beyond 2006 ) is possible.

The problem is that most of the recent increases in sea ice are in these  coastal waters, and  so these are not picked up correctly by the NSIDC.  They update their grids about twice a month, based upon historical interpretations..

JAXA would be better to carry out any meaningful analysis.  But the limits you will have to use will be different to get any reasonable data out of the analysis. Each dataset gives a different value for the amount of sea ice with NSIDC less than Jaxa and this will be less than Masie. That is because  they are measuring different things, and the NSIDC are the least accurate in the areas currently changing, so the answer is almost self-fulfilling, when looking for any increase in coastal ice there.

MIA.

Edited February 15 by Midlands Ice Age

[WYorksWeather]

 Midlands Ice Age Yep, agree that other datasets are better for more detailed analysis of what is going on in each sea ice area. But at the overall Northern Hemisphere sea ice extent level, I imagine the differences you'd see in the trend are probably quite small.

The PDO does seem to me to be a possible explanation for the periods of slower and faster change at the decadal and longer scale. It fits with the 'look' of the graphs quite well. But of course it's highly doubtful that it is just that, and I don't have enough field-specific knowledge to do more than point out correlations.

On shorter timescales, there are probably a lot of other factors. I'd probably always be tempted to say internal variability if we're talking about the last few years only, but of course it may become clear over time that there is a HTHH volcano impact, or an as-yet unknown negative feedback.

 

[Midlands Ice Age]

Thanks  WYW,  I think we have come to a certain degree of agreement.

I too think that there is a natural impact (PDO or something similar ?) now showing in the arctic sea ice data.

Are you aware that the NSIDC also produce a dataset containing all the individual areas extent data going back to 1979? 

Also be aware that there is a difference of about 15% in the total extent figures for any one day (on average), with NSIDC always below other datasets.

If you analysed the Jaxa data at the 'total'  level I am certain that you will get a more meaningful diagnosis as to what is going on, and also will show up more of some of the minor trends - The data in Jaxa for the outer areas is so much more accurate.

Also for Matty.... The Great Lakes are not counted as a part of the sea ice extent data - presumably because it is not salt water. It is however true that I mentioned it in last years reports!!! 

MIA 

 

Edited February 16 by Midlands Ice Age

[johncam]

Oh dear , sea ice in Barents has fell off a cliff literally 

[Aleman]

North American snow only looks to be slightly below average, after several quite high years, making it feel like it is much lower than it should be when it's actually not far off. However, adding to that, the low anomaly periods have been during what are usually the colder months. Without big snowfields to drop temperatures sharply during the longest nights, presumably that means the marginal ice areas in the Great Lakes see less or no ice formed. (Did they go into autumn with higher temperatures this year?)

 

The Northern Hemisphere is not far from average.

 

Edited February 21 by Aleman

[Midlands Ice Age]

On 17/02/2024 at 23:18, johncam said:

Oh dear , sea ice in Barents has fell off a cliff literally 

Hi there again...

Yes Barents has been up and down more times than....

It has since recovered again just as quickly..

Which sort of corroborates my theory about this..

That..  these depressions seem to break up the ice initially on the shelf edge,    (or possibly (more probably I think)  at least allow seawater to ride up over the ice) , and as soon as the swells have subsided then the water drains away and allows the ice to appear for the satellite to 'resee' the ice extent. There could also be genuine refreeze.

This does not mean that the sats are incorrect it more probably means that the lower limit of 15% (or 25% for some datasets to register the area with ice) is past and thus it suddenly registers with no ice.

It seems as though the sea ice 'area'  datasets are not this volatile (they actually count the actual number of ice pixels, and although they will be distorted to some extent will probably be more representative). This again backs up the theory that sea ice extent  reacts to any surface water on  top of the ice. (partic the ice pools which start to form during the melt season)

I will be back later with a more thorough weekly review.

Edited February 22 by Midlands Ice Age

[Midlands Ice Age]

 

Snow continues to be just below average according to Rutgers -

    

The maps still show excess snow cover in China and central Asia, but less in Europe and North America. 

Interestingly this seems not to have not been caused by the snow that has fallen -

Onto sea ice in the northern hemisphere -

Masie sea ice extent has had a rocky  week since the last update with falls of -70K km2, -173K,  -143K, -21k, km2 (mostly in Barents), but then with gains of +23K Km2, +253K, +76K and today +74K Km2 to move the extent back to 15,019K KM2, after dropping to 14,593K KM2 5 days ago.  

 This leaves us top of the ice pile again on Masie.

   

Will it go on to register new 10 year highs in the next (last)  remaining 2.5 weeks of the freezing season? (around day67?). It seems as though the ice extent has been responsive to the Barents low pressure systems.

This has been  corroborated by Jaxa (thanks to the ASIF), which dropped to no 10 in the list, but has also recovered back to no 18 (back to 2005'ish) again now -

    

This is in direct  contrast to the 'area'  graphs ( 5 day average) which show a week of steady gains !

     

So we are now closing in on the maximum for the year which from my previous data can occur around day 66. (6th March?).Will this year beat the last few years now?,  it looks as if the records for the last 20 years have gone out of reach. But this year has been one of surprises...

MIA   

 

 

 

[Aleman]

Talking of Lake Erie last week:

Large ice balls wash ashore at Lake Erie

WWW.BBC.CO.UK

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The phenomenon was seen in Ontario, which has been hit with freezing temperatures this winter season.

 

[danthetan]

Hi @Midlands Ice Age im wondering if you can answer this. I use tropical tidbits for viewing SST on the world map it shows ice in white but has a dark grey area which doesnt make clear what it means? My theory is, its got a thin layer of ice which doesn't reach the threshold of 15% sea ice. In which case the ice has although thin has come along way out from the fram towards Iceland this year.

[Aleman]

I missed the ice bridge from Greenland to Iceland earlier this month:

 

[Midlands Ice Age]

8 hours ago, danthetan said:

 im wondering if you can answer this. I use tropical tidbits for viewing SST on the world map it shows ice in white but has a dark grey area which doesnt make clear what it means? My theory is, its got a thin layer of ice which doesn't reach the threshold of 15% sea ice. In which case the ice has although thin has come along way out from the fram towards Iceland this year.

Have you got a link for me to check as TT is not one of my sources?

MIA

[danthetan]

 Midlands Ice Age

Ocean Analysis | Tropical Tidbits

WWW.TROPICALTIDBITS.COM

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Analysis tools for tracking and forecasting tropical weather

[Midlands Ice Age]

 danthetan

Cannot really help...

If it is on the SST map it could be the water temp below zero.

Remember that salty water doesn't freeze until -2C is reached not zero.

MIA

Edited February 27 by Midlands Ice Age

[Midlands Ice Age]

Almost a week since my last update, and since we are now 95%  thru to the expected maximum date, thought that an update with some  data might be useful.

Snow levels have not changed much and the snow extent (as opposed to what has fallen) is still below average.

 

No real changes are currently forecast.

Sea ice extent has risen to above 15,000K Km2 again and is now at 6days above for this year. (for comparison of past, see annual data below).

Change over the last 6 days have shown (-67K), (-26K)  - (below 15M) - and then (+156K) and (-32K, (-33K) and finally (-3k). 

These changes have occured due to still larger increases in the SOO, and when Barents and Baffin Bay increased we had the very large total increase.

    

There is now about 7 days to the expected maximum in extent. Area will follow shortly afterwards, and volume will peak at the end of March - due to continued bottom freezing.

However I thought it may be interesting over the next few weeks to see how the extent varies with respect to the last 17 years, by examining the number of days that the ice stays above 15.000K Km2. 

Year    First date past 15M          Maximum           Number of days over 15M

2024          042                                15072K                       6 (so far)

2023          064                                 15005                         1

2022          059                                 15065                         4

2021         

2020           061                                 15129                         6 

2019

2018 

2017

2016            057                                15077                            5

2015   

2014             051                               15298                            35

2013             041                               15550                            56

2012             047                                15296                           55

2011             066                                15081                             6

2010              049                               15298                            42

2009              048                               15326                            10

2008              057                               15651                             68 

Could be interesting to see in a few weeks time.

Temperature in the Artic circle has been slowly dropping over the last 32weeks but is still above the olden days of last century. 

 

Another update nearer the expected maximum,   early next week., when the February monthly averages will be available.

MIA                                                                                                                                                                                            

Edited February 28 by Midlands Ice Age

[BleakMidwinter]

 Midlands Ice Age

 

I found this very interesting - spraying seawater onto the surface of sea-ice to increase its thickness and resilience- only at initial stages of research testing on thin layers at present, and not considered a 'cure' but could at least help in some areas where loss of sea ice affects the area more widely...
 

Pumped up: will a Dutch startup’s plan to restore Arctic sea-ice work? | Polar regions | The Guardian

WWW.THEGUARDIAN.COM

---

As the Arctic warms, devastating the climate and ecosystems, an old idea used to create skating rinks could be deployed to restore melting ice caps, despite scepticism from some experts

 

[nobble]

 BleakMidwinter interesting read food for thought 

[johncam]

A large drop over the last few days , think it has peaked for this winter 

[Midlands Ice Age]

 johncam

Yep, almost certainly we have passed the largest extent date  for this year on the  29th Feb.

After the previous high of 15,088K 3 days earlier,  we immediately had a large drop of 169K then followed by 3 smaller falls.

This reduction took the level down to 14,737K (well below the 'magic' 15M figure I was monitoring).

Since then the ice has been increasing slowly on average after an initial  steep rise of  +189k put us within reach of the magic marker of 15M again. But it failed to cross the boundary.

  

So looking unlikely now that we will create a new maximum (Or even exceed 15M again), but it could well have  happened around 10 years previously  - when freezing stalled at these levels for about 2 -3 weeks before dropping -  so we never know. 

We are now in the gap between the end of 'extent' increases, but 'area' is likely to continue to increase for the next 6 days.

NSIDC 'area' is indeed showing late increases and we now have both area and extent appearing around 10 -12th in the tables for the last 20 years. (Graphs thanks to the ASIF).

    and

     for area, and

  and 

   for extent.

Laying snow is still just below average..

It is still not too late that we may see a sudden spurt in all these numbers as colder air has returned to the Arctic environments and northern hemisphere in general as shown both by the DMI (above 80 degrees), and also the  ECM climate above 60 degree maps -

     

An early look at the volume map shows that it has slipped into last position in the last few months,  this despite much more ice in the eastern part of the globe. -

 Definitely caused by the slow ice season in the western sea areas.

Nearly at the end of the ' growth '  season now, so my reports will slowly be dwindling...

MIA 

[Midlands Ice Age]

On 08/03/2024 at 16:18, Midlands Ice Age said:

Yep, almost certainly we have passed the largest extent date  for this year on the  29th Feb.

After the previous high of 15,088K 3 days earlier,  we immediately had a large drop of 169K then followed by 3 smaller falls.

This reduction took the level down to 14,737K (well below the 'magic' 15M figure I was monitoring).

Since then the ice has been increasing slowly on average after an initial  steep rise of  +189k put us within reach of the magic marker of 15M again. But it failed to cross the boundary.

  

So looking unlikely now that we will create a new maximum (Or even exceed 15M again), but it could well have  happened around 10 years previously  - when freezing stalled at these levels for about 2 -3 weeks before dropping -  so we never know. 

Well now we do!!!!!

A HUGE (just about unexpected - see above)  exceptional increase of (+237K) takes the Masie sea ice extent total to a season's high of 15,114K Km2. 

  

Barents was the major driver with a sudden spurt of 90K KM2 . Other areas such as Bering (+48K), SOO (+29k),  and Baltic (+22K)  suddenly leapt into life again after a dormant 3 or 4 days.

One may ask why this has occurred when we are supposedly past the point at which extent has not increased any further, over the last 8 years. It did however increase in many years prior to 2014!! Just perhaps...... ? (look at my 15M charts above).

However I looked at the 'mechanism' of the increase in more  detail and my main thought is that we have seen the same effect I have identified on  2 or 3 occasions so far this season...

-  That of sea salty water laying on top of the ice, and this, I believe, confuses the satellite recording data.

I believe that the ice has been still there all the time and that it still will then show up again after the water either drains or perhaps the surface refreezes.

MIA's theory strikes again..

It will be more interesting to see if it is (as is possible) a straight satellite error in which case it will have a large drop again tomorrow.

The temperature (after its reduction after the last few days) has again risen so that really has had no direct impact. (warmer temps have caused more ice on a few occasions!!!)

There is still life in the Arctic.

The ASIF forum has indicated that this season has seen about a 5% increase in ice growth this year compared to the 2010 era, with the last 3 seasons showing an increase compared to the ongoing trend lines.

     

This trend coincides with the onset of La Nina. Now we are in an El Nino, so lets await the summer melt season with interest. 

Could well be back again if this totally unusual and surprising  freezing season continues on its merry way.

MIA

[Midlands Ice Age]

Yet another surprising update..

The last 4 days have seen the sea ice extent on Masie actually increase to over 15M Km2.

  

This mornings NSIDC predict another increase today to possibly yet another new high.

The remarkable thing is that -

1) the experts on the ASIF have already called called the end of the extent refreeze season back 2 weeks ago.

2) there seems to be little weather difference to cause these large deviations

3) the temperature of the Arctic DMI (above 80 degrees) is still rising (since Mar1st) and the Northern hemisphere temperatures are still 1 degree above normal.

      

4) Arctic 'area' is still (steadily?) increasing although normally we should just have started to fall by now -

(thanks to the ASIF)

           

    and for extent we have -   

Both 'area' and extent are in the mid teens in terms of the last 18 years, and are now challenging some of the early year dates. All this after an unexpected drop in late February.

Why is this happening?

Well unless the 'volume' numbers start to increase again I am not certain it is a long term feature change.

And my thoughts (for what they are worth?) is that it definitely has some thing to do with  the ENSO and  the  long (3 year?) La Nina pattern set up prior to last summer. It seems as though this pattern still is persisting in the Arctic, even though it has been over-ridden by a large El NIno over the last 9 months for the rest of us. It is also noteworthy that the ENSO forecasts now predict a fall back into neutral of even a further La Nina. 

The second of my thoughts  on the subject are that we have this year seen a 'difference' in the weather patterns across the northern hemisphere with much colder air over 'Asia' , whilst much warmer air (compared to the last 10 years)  has been sitting over the N American continent.  This has caused the following in terms of ice production -

   whilst the much smaller Labrador Straits have virtually no ice - 

The differences are enormous!!

Also we have not seen these conditions with large Asian ice conditions for about 10 years.

Is this why the sea ice in the last 10 years has been subsiding, since we do seem to have increased more recently, and especially now with this totally unexplained increase?

And finally  another impact on short term ice (according to day to day satellites) is (I believe) the recently noticed impacts of thin sea ice at the edge of the pack been overridden by the sea. producing incorrectly low ice numbers at times. These, even now. appear to be producing the rapid increases in ice 'accumulations' despite it being beyond the date of refreeze.

As we seem to be still increasing in ice for the moment  , I will continue to report a little longer into the melt season this year as I feel it is worthwhile that these events are reported somewhere so that these can improve the more long term Arctic forecasting. 

To show the effects of the increase I will be updating the long-term 15M KM2 table that  I started recently in a later review. 

MIA

Edited March 12 by Midlands Ice Age