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Aluminium

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Re: The 2019/2020 freezing season
« Reply #850 on: February 04, 2020, 01:34:17 PM »
January 22 - February 3.

2019.

Glen Koehler

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Re: The 2019/2020 freezing season
« Reply #851 on: February 04, 2020, 05:29:09 PM »
Therefore, I experimented with instead normalizing the years to their predicted average extent from a linear regression of all the years.
Your method is skewed by the fact that the long-term extent losses are happening more rapidly in September than in January/February/March.

September extent in the last few years is about 40% lower than in the 1980s, whereas March extent has decreased by only 10%.  So your "normalized" March extent has an upward trend over the last few decades, whereas the normalized September extent has a downward trend.  So it's not surprising that you get a negative correlation between them.  But that correlation is spurious.

A more meaningful method is to detrend the data (see e.g. here for some background on detrending).  It turns out that the correlation between the detrended March extent and the detrended September extent is very weak: the correlation coefficient is  -0.029.

    Many thanks to grixm and Steven et al. for wrestling with the numbers.  It looks like the jury is still out on this one.  While counter-intuitve [more Extent early leads to less 8 months later (Jan-Sept), 7 (Feb-Sept.), or 6 March-Sept.)], the insulating ice theory at least sounds plausible. 

    But assuming Steven's -0.029 correlation coefficient for March-September Extent is correct, that is low even for noise, and certainly not signal.  I find such a low correlation equally counter-intuitive.  My naive guess is that there would be some influence of March Extent on September Extent only 6 months later.

    Which leaves me even more jaded about Extent as being a flukey measure for status of the Arctic sea ice.  It is a real thing, and the most directly measurable, so I'm not discrediting it entirely.  But this episode seems to demonstrate that caution is needed in equating the annual maximum or minimum Extent as a precise measuring stick for ASI status and trend.  It is what it is, and the long-trend in Extent decline certainly shows us a real effect, but for year to year, or within-year, comparisons it seems too variable to draw short-term conclusions or predictions.

    If anybody is up for graphing a detrended March vs. September average Volume, that might be more conclusive.  But even that would still be subject to unknown melt season weather.  Given the considerable year to year variation we see in Volume also, as shown in the recently updated Wipneus PIOMAS volume graphs --
https://sites.google.com/site/arctischepinguin/home/piomas
it seems that what we need is a skilled forecast for melt season weather. 

    My amateur foray into estimating forecast skill at 6-9 month range for midlatitude U.S. (45 degrees N, 69W) temperature and precip found a little bit of skill beyond climatology out to 6 months for temperature, but nothing worth mentioning for precip beyond about a month.  ASI melt weather seems strongly influenced by clear vs. cloudy skies.  The inability to forecast precip at a more intensively monitored and presumably better understood temperate mid-latitude location beyond a month suggests that we will not have skillful multi-month Arctic melt season forecasts anytime soon.  So we'll just have to wait and see what happens in 2020.

    But there's still room for some alarmist notification and unmitigated voodoo.  The Wipneus exponential volume trend puts the 2020 Sept. minimum more than 1 million km3 BELOW 2012.  I put more faith in the straight line trend, but even that puts 2020 at matching the 2012 record low. 

     As for the voodoo,
1) the recent low snow cover post by Pavel https://forum.arctic-sea-ice.net/index.php/topic,2888.msg247615.html#msg247615,
2) the speculation by El Cid about a cold Alaska winter leading to a strong melt season. https://forum.arctic-sea-ice.net/index.php/topic,2888.msg247815.html#msg247815
3) the continuing trend to thinner ice and recent obliteration of old thick ice
4) and the animated ice pack image posted above by Alumimiun - which looks to me like the Atlantic front is already retreating (though that could just be daily variation) -
have got me suspecting that 2020 could have a very active melt season.  Maybe that will bring necessary attention to the larger problem.   
     
 

« Last Edit: February 04, 2020, 06:10:14 PM by Glen Koehler »

gandul

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Re: The 2019/2020 freezing season
« Reply #852 on: February 04, 2020, 07:45:23 PM »
The Winter of 16/17 was very warm in the Arctic and the ice was crazy record low in volume starting the 2017 summer season. However, that was a warm Arctic / cold continents winter with very deep snow cover in the Northern Hemisphere, especially Siberia. Thus, Spring and summer were really late, and there were not many warm punches from the continents, rather the contrary.

This winter is kind of the opposite with this very persistent and strong Polar Vortex. However, note that the polar vortex has displaced the Arctic warm anomalies accumulated in Summer and vented out in Fall, to the high and mid latitudes of the NH. In fact it is really warm relatively speaking, probably one of the warmest Januaries for the NH.
There is an astounding lack of snow cover in Europe, and also a relative lack in America. The heat may come to the Arctic with a vengeance in the form of a very early NH Spring. Pray that it snows soon. An early Spring due to lack of NH snow cover is for me probably the most determining factor to start a warm melting season. True that Arctic winter is being cold and more benign for the ice but Wipneus just showed PIOMAS volume is 5th lowest in record. Not really impressive. 
Edit: Zack Labe reports a January anomaly of 3C !! Not sure if that is global or only Europe...
« Last Edit: February 04, 2020, 07:52:17 PM by gandul »

grixm

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Re: The 2019/2020 freezing season
« Reply #853 on: February 04, 2020, 08:11:40 PM »
Therefore, I experimented with instead normalizing the years to their predicted average extent from a linear regression of all the years.
Your method is skewed by the fact that the long-term extent losses are happening more rapidly in September than in January/February/March.

September extent in the last few years is about 40% lower than in the 1980s, whereas March extent has decreased by only 10%.  So your "normalized" March extent has an upward trend over the last few decades, whereas the normalized September extent has a downward trend.  So it's not surprising that you get a negative correlation between them.  But that correlation is spurious.

A more meaningful method is to detrend the data (see e.g. here for some background on detrending).  It turns out that the correlation between the detrended March extent and the detrended September extent is very weak: the correlation coefficient is  -0.029.

    Many thanks to grixm and Steven et al. for wrestling with the numbers.  It looks like the jury is still out on this one.  While counter-intuitve [more Extent early leads to less 8 months later (Jan-Sept), 7 (Feb-Sept.), or 6 March-Sept.)], the insulating ice theory at least sounds plausible. 
[..]

I normalized the months to the trend of its month alone, instead of to the whole year, like pointed out. And it seems Steven is correct. The correlation is gone..




Glen Koehler

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Re: The 2019/2020 freezing season
« Reply #854 on: February 04, 2020, 08:48:05 PM »
Thanks grixm!

harpy

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Re: The 2019/2020 freezing season
« Reply #855 on: February 05, 2020, 05:09:28 PM »
The Winter of 16/17 was very warm in the Arctic and the ice was crazy record low in volume starting the 2017 summer season. However, that was a warm Arctic / cold continents winter with very deep snow cover in the Northern Hemisphere, especially Siberia. Thus, Spring and summer were really late, and there were not many warm punches from the continents, rather the contrary.

This winter is kind of the opposite with this very persistent and strong Polar Vortex. However, note that the polar vortex has displaced the Arctic warm anomalies accumulated in Summer and vented out in Fall, to the high and mid latitudes of the NH. In fact it is really warm relatively speaking, probably one of the warmest Januaries for the NH.
There is an astounding lack of snow cover in Europe, and also a relative lack in America. The heat may come to the Arctic with a vengeance in the form of a very early NH Spring. Pray that it snows soon. An early Spring due to lack of NH snow cover is for me probably the most determining factor to start a warm melting season. True that Arctic winter is being cold and more benign for the ice but Wipneus just showed PIOMAS volume is 5th lowest in record. Not really impressive. 
Edit: Zack Labe reports a January anomaly of 3C !! Not sure if that is global or only Europe...

Right, because as the sun incidence increases over the next 30 days, it will act as a positive feedback loop on global warming when all of the landmass is dark and absorbent.

Thank you for pointing this out. 

Glen Koehler

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Re: The 2019/2020 freezing season
« Reply #856 on: February 05, 2020, 06:36:15 PM »
RE grixm
https://forum.arctic-sea-ice.net/index.php/topic,2888.msg247928.html#msg247928

     I thought we were done with this, but I have another favor to ask.  Can you extend the early vs Sept. Extent comparison charts to April-August? 

    You showed above that there is no correlation of March to September, but surely there must be correlation by August.  This is probably in a journal article somewhere, but your charts are lovely and can be up to date to include 2019.  Seeing the data point spread would be really interesting.   

     For sporting interest, I'll wager such charts would show R2 around:
April 10%
May 20%
June 30%
July 50%
August 80%

    And if anybody did the same for Volume, that would be icing on the cake.

PS in case you zipped past binntho's post in the data thread at
https://forum.arctic-sea-ice.net/index.php/topic,2975.msg247842.html#msg247842
   The articles he cites there provide really nice long-term context for ASI variability and current situation.  Good stuff.
« Last Edit: February 05, 2020, 06:53:01 PM by Glen Koehler »

grixm

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Re: The 2019/2020 freezing season
« Reply #857 on: February 05, 2020, 07:39:22 PM »
RE grixm
https://forum.arctic-sea-ice.net/index.php/topic,2888.msg247928.html#msg247928

     I thought we were done with this, but I have another favor to ask.  Can you extend the early vs Sept. Extent comparison charts to April-August? 

    You showed above that there is no correlation of March to September, but surely there must be correlation by August.  This is probably in a journal article somewhere, but your charts are lovely and can be up to date to include 2019.  Seeing the data point spread would be really interesting.   

     For sporting interest, I'll wager such charts would show R2 around:
April 10%
May 20%
June 30%
July 50%
August 80%

    And if anybody did the same for Volume, that would be icing on the cake.

PS in case you zipped past binntho's post in the data thread at
https://forum.arctic-sea-ice.net/index.php/topic,2975.msg247842.html#msg247842
   The articles he cites there provide really nice long-term context for ASI variability and current situation.  Good stuff.










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Re: The 2019/2020 freezing season
« Reply #858 on: February 05, 2020, 07:45:36 PM »
Nice!  Thanks!

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Re: The 2019/2020 freezing season
« Reply #859 on: February 06, 2020, 12:12:17 PM »
Wipneus just showed PIOMAS volume is 5th lowest in record. Not really impressive.

However further to previous discussions the "measured" volume using CryoSat-2/SMOS data is significantly lower than PIOMAS this year:



In case it's of interest the source code for the program that crunched the numbers and the resulting raw "measured" volume data can be downloaded over at:

"CryoSat-2/SMOS Arctic Sea Ice Volume"

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Re: The 2019/2020 freezing season
« Reply #860 on: February 06, 2020, 12:47:01 PM »
Nice!  ;D

weatherdude88

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Re: The 2019/2020 freezing season
« Reply #861 on: February 06, 2020, 01:13:45 PM »
Northern hemisphere snow cover is well below average this winter.



However, the snow water equivalent (the total volume) is significantly above the 1998-2011 average.



The higher latitude regions that have snow cover, have a lot of it.




As we approach the end of the 2019/2020 freezing season, we may have more ice and snow volume, in harder to melt areas at higher latitudes, than all years in the previous decade.

There is an astounding lack of snow cover in Europe, and also a relative lack in America. The heat may come to the Arctic with a vengeance in the form of a very early NH Spring.

To the contrary, we may have an extended 2019/2020 freezing season. The 2020 northern hemisphere sea ice melting season may get off to a slow start.

There has been significant focus on the lack of snow extent cover, at lower latitude and easier to melt regions, even though we have near record snow/ice volume in the more difficult to melt regions.
« Last Edit: February 06, 2020, 01:24:00 PM by weatherdude88 »

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #862 on: February 06, 2020, 01:18:45 PM »
However, the snow water equivalent (the total volume) is significantly above the 1998-2011 average.

However, where albedo is concerned surely area is more relevant than thickness? Whether one is talking about sea ice or snow cover!

http://GreatWhiteCon.info/2020/01/wheres-the-thickest-arctic-sea-ice-gone/#comment-313127

Quote
As I have stated numerous times, let’s see how things look in May before jumping to any hasty conclusions about what the 2020 Arctic sea ice melting season might bring?
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

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Re: The 2019/2020 freezing season
« Reply #863 on: February 06, 2020, 03:14:49 PM »

There has been significant focus on the lack of snow extent cover, at lower latitude and easier to melt regions, even though we have near record snow/ice volume in the more difficult to melt regions.
In february and march the lower latitudes are more important in terms of albedo while the higher latitudes snow cover become important in May/June. We have now extra heat absorbing in 3 mln sq km of land

The Walrus

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Re: The 2019/2020 freezing season
« Reply #864 on: February 06, 2020, 04:45:41 PM »

There has been significant focus on the lack of snow extent cover, at lower latitude and easier to melt regions, even though we have near record snow/ice volume in the more difficult to melt regions.
In february and march the lower latitudes are more important in terms of albedo while the higher latitudes snow cover become important in May/June. We have now extra heat absorbing in 3 mln sq km of land

True, but how relevant is it to Arctic sea ice.  Much if the lower latitude snow cover can be correlated with temperatures (melt is significant as temperatures rise above freezing).  Using the average January temperature in Chicago (using other U.S. cities will yield comparable results), since 1998 (the year the ice started its precipitous decline), there is no correlation with Arctic sea ice.  The trend line is completely flat.  The warmest January averages (prior to this year) were 2006, 2002, 2012, 1998, and 2017 respectively. 2012 is a noteworthy year, but the others are unremarkable.  Two resulted in declining sea ice at minimum, while two yielded increasing sea ice.  The warmest year, 2006, was one of the highest year-over-year sea ice gains.  The coldest years were 2014, 2009, 2004, 2011, and 2019 respectively. 

One could argue that this analysis of increased temperatures and decreased snow cover only covers the lower latitudes of North America.  Interestingly enough, the warmest January in Chicago (2006) corresponded to the second coldest January in Fairbanks, Alaska, and the coldest (2014) was the second warmest.

gandul

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Re: The 2019/2020 freezing season
« Reply #865 on: February 06, 2020, 06:06:27 PM »
Northern hemisphere snow cover is well below average this winter.
...
There is an astounding lack of snow cover in Europe, and also a relative lack in America. The heat may come to the Arctic with a vengeance in the form of a very early NH Spring.

To the contrary, we may have an extended 2019/2020 freezing season. The 2020 northern hemisphere sea ice melting season may get off to a slow start.

There has been significant focus on the lack of snow extent cover, at lower latitude and easier to melt regions, even though we have near record snow/ice volume in the more difficult to melt regions.
Fair enough, if the volume at high latitudes is so high, we'll see. One thing though, the second plot you show, snow volume, is every year the same anomalously high. Not very useful.

ArcticMelt2

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Re: The 2019/2020 freezing season
« Reply #866 on: February 06, 2020, 06:45:18 PM »
Snow area in January ranked third in the 21st century after 2007 and 2014.

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Re: The 2019/2020 freezing season
« Reply #867 on: February 06, 2020, 07:32:50 PM »
Snow area in January ranked third in the 21st century after 2007 and 2014.
I assume you mean third lowest? What's the source of the data?

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #868 on: February 06, 2020, 07:47:11 PM »
One thing though, the second plot you show, snow volume, is every year the same anomalously high. Not very useful.

See for example:



There's plenty more where that came from:

http://www.globsnow.info/swe/GCW/
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be cause

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Re: The 2019/2020 freezing season
« Reply #870 on: February 06, 2020, 09:33:04 PM »
you would never guess there is a thread for northern hemisphere snow cover .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

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Re: The 2019/2020 freezing season
« Reply #871 on: February 06, 2020, 11:18:15 PM »
You showed above that there is no correlation of March to September, but surely there must be correlation by August.

As an addition to grixm's graphs, below is a table showing the correlations between detrended monthly sea ice extent data for each possible combination of months, from January to December.  For the calculation, I used the NSIDC extent data for 1979-2019.  The detrending that I'm using is slightly different from the one used by grixm, but the results seem to agree very well with his.

Note that the table shows the monthly correlation coefficients R rather than the squared correlations R^2, and it  has some grey background colors to indicate the strength of the monthly correlations, with darker colors indicating stronger correlations:

(click to enlarge the image)




The most noteworthy feature to me is the lack of correlation between May and June.  I guess it's because the weather conditions and preconditioning in late May and in June play a very important role for the rest of the melt season.  That time of year is basically the start of the melt pond season in the Arctic proper.

And here is a similar graph for monthly PIOMAS volume data, rather than extent.  As expected, the correlations are much stronger in that case.

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Re: The 2019/2020 freezing season
« Reply #872 on: February 06, 2020, 11:23:36 PM »
for the ice but Wipneus just showed PIOMAS volume is 5th lowest in record. Not really impressive. 
Edit: Zack Labe reports a January anomaly of 3C !! Not sure if that is global or only Europe...

Considering that Extent is between 10th and 15th and volume is 5th lowest that tells me at least a big story and is very impressive indeed.

The point is that ice must be significantly thinner than back in time when extent was around that and volume in similar positions.

If we further put into account that piomas is most probably on the "optimistic" side, there are indicators that this is so, everything is even worse and therefore way more impressive.

Since this trend is continuing if not accelerating a few of the not impressed will have a nasty wakeup call in the not so distant future. Better be prepared.

binntho

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Re: The 2019/2020 freezing season
« Reply #873 on: February 07, 2020, 06:50:16 AM »
Moved from the data thread after a kindly reminder ...  8)

Before we all start to get too expressive about excessive extent, I'd like to point out that we are talking about comparatively small differences between the various years. Random weather effects  such as wind driven export could easily account for all the variation we see in the last decade.

And of course, as much cleverer people than me have decisively shown (I trust ...) there is absolutely no correlation with summer extent. Which tempts me to conclude that there is no correlation with temperatures either - i.e. winter extent will be more or less what we are seing now, with small random variations, until at some point in a (probably) distant future when winter refreezes doesn't manage to fill the entire Arctic.
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Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #874 on: February 07, 2020, 02:24:50 PM »
Considering that.... volume is 5th lowest that tells me at least a big story

That depends on which metric you look at. At the risk of repeating myself:



Reality is merely an illusion, albeit a very persistent one - Albert Einstein

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Re: The 2019/2020 freezing season
« Reply #875 on: February 07, 2020, 02:27:37 PM »
you would never guess there is a thread for northern hemisphere snow cover .. b.c.

There doesn't seem to be an adequate emoticon, in which case ROFL!

ASIF topic #103:

https://forum.arctic-sea-ice.net/index.php/topic,103
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Re: The 2019/2020 freezing season
« Reply #876 on: February 07, 2020, 02:53:09 PM »
Considering that.... volume is 5th lowest that tells me at least a big story

That depends on which metric you look at. At the risk of repeating myself:



At the risk of sounding stupid, there is 3 lines there upto the current date, 2 of them are dashed lines in totally different positions so what does that graph tells us? Should we just look at the solid red line and suggest volume is at 2nd lowest just above 2017(despite being totally opposite freezing seasons). Also I'm sure I read in the past that crysosat may get confused with snow on the ice itself?

PIOMAS may not be perfect but it does seem more realistic given the freezing season so far?

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Re: The 2019/2020 freezing season
« Reply #877 on: February 07, 2020, 03:57:43 PM »
The dashed lines are the upper/lower bounds. I would just go with the red line. This is rather new so in a couple of years we will know when it is becoming less reliable in the year and how it compares to PIOMAS or even better measures if available...
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Re: The 2019/2020 freezing season
« Reply #878 on: February 07, 2020, 04:26:34 PM »
Actually I looked at that chart again and it suggests the start of 2013 has the lowest volume on record despite 2013 having a better refreeze season after the record melt.

Not sure I fully trust that chart to be honest, all that said things can change rapidly in the Arctic so anything can happen by September.

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Re: The 2019/2020 freezing season
« Reply #879 on: February 07, 2020, 04:48:20 PM »
"The coldest January on Kodiak is the forerunner of the big summer ice loss? Top 10 includes January 2007 and 2012."

I think there might be some truth to that. Alaska is cold during the winter and Europe/lower 48 US is warm when the polar vortex is well behaved and no "cold-spills" reach them. Due to this there is usually little snowcover in NH midlatitudes so when spring comes they should warm up fast. This could of course lead to a fast meltout of the periphery in the Arctic which - given good weather - would lead to fast ice loss especially as there is not much old ice nowadays.

There are many ifs though...but I think we have a good chance of seeing some "fireworks" during this summer in the Arctic

A similar picture throughout Alaska

Quote
January 2020 was plenty cold in Alaska, but it did not crack the bottom ten for Alaska over the past 96 years. There is not a significant linear trend over that time, but there is a well defined "step" increase in the mid-1970s. #akwx #Arctic @Climatologist49


Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #880 on: February 07, 2020, 07:32:26 PM »
Actually I looked at that chart again and it suggests the start of 2013 has the lowest volume on record.

From the summer of 2013:

http://GreatWhiteCon.info/resources/arctic-sea-ice-images/summer-2013-images/

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gerontocrat

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Re: The 2019/2020 freezing season
« Reply #881 on: February 07, 2020, 10:15:13 PM »
Looks like much of Canada in the deep freeze for the next 4 weeks.

https://weather.gc.ca/saisons/image_e.html?img=mfe1t_s

Not often you see a 100% expectation of below normal temperatures over such a large swath of the Canadian far North
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Re: The 2019/2020 freezing season
« Reply #882 on: February 07, 2020, 10:23:46 PM »
Actually I looked at that chart again and it suggests the start of 2013 has the lowest volume on record.

From the summer of 2013:

http://GreatWhiteCon.info/resources/arctic-sea-ice-images/summer-2013-images/

But the lowest volume was recorded during the winter of 2013 according to that chart and not during the summer when that chart of the pole  was posted.

I find it (very) hard to believe that volume in 2017 is higher than it was in 2013 and this year given how warm the 16/17 winter was. The theory that crysosat confuses heavy snow cover for volume could well be the case here as lots of snowfall must of fell onto the ice pack giveen how much moisture headed upto the pole that winter.

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #883 on: February 07, 2020, 10:40:44 PM »
The theory that crysosat confuses heavy snow cover for volume could well be the case here as lots of snowfall must of fell onto the ice pack giveen how much moisture headed upto the pole that winter.

I'm not sure that adequately describes "the theory". CryoSat makes some assumptions about snow cover when it converts freeboard measurements to ice thickness. There's plenty more on all that sort of thing over on ASIF topic #8:

"PIOMAS vs CryoSat"
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edmountain

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Re: The 2019/2020 freezing season
« Reply #884 on: February 07, 2020, 10:52:22 PM »
Not often you see a 100% expectation of below normal temperatures over such a large swath of the Canadian far North
I think it's technically in the 90-100% range. But still unusual for sure.

NotaDenier

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Pavel

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Re: The 2019/2020 freezing season
« Reply #886 on: February 09, 2020, 11:18:58 AM »
The Laptev sea has the huge areas of the new thin ice. The wind pattern in the next days will continue to push the ice toward the Fram strait.

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #887 on: February 09, 2020, 12:33:14 PM »
Together with the latest CS2/SMOS volume. The "blip" at the end of January will probably disappear when the "reanalysed" data reaches that date:
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Niall Dollard

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Re: The 2019/2020 freezing season
« Reply #888 on: February 09, 2020, 03:16:12 PM »
ESRL ice thickness for 8th Feb 2020, also showing the thin ice in Olenekskiy Bay (Laptev Sea) as mentioned by Pavel.

Contrast ESRL ice thickness from just over a year ago (end of Janaury 2019) 

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #889 on: February 09, 2020, 04:43:38 PM »
7-day hindsight mean temperature anomalies, Sunday to Sunday.

blumenkraft

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Re: The 2019/2020 freezing season
« Reply #890 on: February 09, 2020, 04:51:38 PM »
Last weeks Fram export via SAR

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #891 on: February 11, 2020, 12:43:27 PM »
Together with the latest CS2/SMOS volume. The "blip" at the end of January will probably disappear when the "reanalysed" data reaches that date:

Stefan Hendricks has just explained "the blip":

https://spaces.awi.de/display/SIRAL/2020/02/11/CryoSat-2+-+missing+NRT+data+in+baseline-D

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The NRT Level-1 data to the CryoSat-2 sea ice product is missing several orbits, mostly in the Russian Arctic.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

grixm

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Re: The 2019/2020 freezing season
« Reply #892 on: February 12, 2020, 11:03:12 AM »
Look at all these polynyas and cracking in the ESS/Laptev. Is this normal during peak freeze season?


be cause

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Re: The 2019/2020 freezing season
« Reply #893 on: February 12, 2020, 11:43:13 AM »
 ^^ yes .. take a look at last year for example .. the ice leaving Fram or ridging must be replaced . This is where it mostly happens to happen .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

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Re: The 2019/2020 freezing season
« Reply #894 on: February 12, 2020, 12:26:36 PM »
It's normal to see polynya and ridging along the fixed ice line. Not so sure about the large radial leads. https://go.nasa.gov/39ujJ38 (suomi/npp only goes back to sep2017)

Animation here

ArcticMelt2

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Re: The 2019/2020 freezing season
« Reply #895 on: February 12, 2020, 12:42:33 PM »
https://twitter.com/AlaskaWx

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Bering Sea #seaice continues to increase & total extent is now almost at the 1981-2010 median for the date from @NSIDC data. Bering ice at the highest extent for early February since 2013. Increase this week mostly near Chukotka. #akwx #Arctic @Climatologist49 @KNOMnews @KYUKNews


blumenkraft

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Re: The 2019/2020 freezing season
« Reply #896 on: February 12, 2020, 01:47:09 PM »
Now that is strange, really different Arctic circulation patterns countinue

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Yes a Cyclone from the Atlantic is heading to the Pacific straight from East to West.  Because the CTNP,  the North American Cold Temperature North Pole vortice is well South of the Canadian Arctic Archipelago.   Is quite warm over Ellesmere Island at present compared to further South.  Even though Ellesmere is still plunged in 24 hour darkness.   All in all, 19-20 winter is no recent year pattern repeat.  This feature announces more strangeness to come.

Link >> https://eh2r.blogspot.com/2020/02/now-that-is-strange-really-different.html

dnem

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Re: The 2019/2020 freezing season
« Reply #897 on: February 12, 2020, 03:56:16 PM »
Is vortice a word? Vortex singular; vortices plural, no?

Jim Hunt

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Re: The 2019/2020 freezing season
« Reply #898 on: February 12, 2020, 07:02:27 PM »
Last week ARCUS held a webinar on my favourite topic. “Ocean Waves in the New Arctic”, presented by Jim Thomson from the University of Washington.

Here's the story of how I only managed to watch the second half live:

http://GreatWhiteCon.info/2020/02/jim-thomson-waves-in-ice-webinar/

and here's the recording:



Essential viewing. IMHO!
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

gerontocrat

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Re: The 2019/2020 freezing season
« Reply #899 on: February 12, 2020, 07:31:01 PM »
Is vortice a word? Vortex singular; vortices plural, no?
Does the name of a company count as a word?

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