Arctic Sea Ice Extent, Area, and Volume

[FallsLake]

49 minutes ago, Typhoon Tip said:

Mm...  No not likely.   "Year round," as in 'never' gaining ice back at all?  That's not likely to be a reality in anyone's lifetime.   

If you/we mean that N. Hemisphere summers experience transient open sea conditions; that may occur at some point. Who knows if that would be a decade.  Timing such a reality would depend upon how "accelerated" the acceleration is, as per recent studies go. 

There will be an ice-cap-transition period where there are summers with open seas that fluctuate back to ice cover the following winters.  In fact, it's entirely possible that would happen with irregularity, too - some years the summer retains a small ice-cap, and then the next year ... the summer sees it disappear again. Only to repeat either scenario. 

That may go on for quite a while actually, long before any kind of Paleo./eocene thermal max -related sort of redux fully takes over. 

Anyway, there's going to be some growing pains. These longer term changes can and do take place in shorter orders of time, and acceleration in the present climate models, as well as empirical data do send alarming signals that "shorter" may favored over longer. But, we have to remember, shorter in the context of geology is still a bit of an existential misnomer. 

But this is not to dissuade you  It's better for the world if folks are open-minded, vigilant toward more dire plausibility, because obviously it is the dire realities that cause the extinctions - not the relative utopias.

 

 

We also don't know about any feedbacks that may occur with more open water. Siberia (land mass) is still going to get very cold during the fall/winter months. When this air traverses over open water it will pick up moisture and then dump it as snow somewhere else. Most of the Arctic is considered a desert and increasing the winter snow accumulations will have an impact on the spring melt season; which in turn could slow the following years ice melt.  **just agreeing with you that we don't know exactly how things will play out....     

[bluewave]

This is one of the most extreme dipole reversals on record for late August. The Arctic went from record high pressures to record low pressures in just a few weeks. It’s the first time in over a decade for a small gain in extent from 8-22 to 8-27. Shows what can happen with a rapid shift to colder and stormier conditions.

8-22 to 8-27 sea ice extent change

2019...+55k

2018...-134k

2017...-213k

2016....-507k

2015....-451k

2014....-165k

2013....-152k

2012....-431k

2011....-177k

2010....-262k

2009....-254k

2008....-439k

2007.....-71k

 

[Typhoon Tip]

3 hours ago, bluewave said:

This is one of the most extreme dipole reversals on record for late August. The Arctic went from record high pressures to record low pressures in just a few weeks. It’s the first time in over a decade for a small gain in extent from 8-22 to 8-27. Shows what can happen with a rapid shift to colder and stormier conditions.

8-22 to 8-27 sea ice extent change

2019...+55k

2018...-134k

2017...-213k

2016....-507k

2015....-451k

2014....-165k

2013....-152k

2012....-431k

2011....-177k

2010....-262k

2009....-254k

2008....-439k

2007.....-71k

 

Fwiw -the GEF -based NAM numbers have been elevating and in fact, are positive in the initialization as of last night.  They are forecasting a brief dip back to neutral or perhaps modestly negative SD, before an even more robustly positive modality out toward week two. 

This observation of reversing pressure patterns is probably related to that - 

I haven't see then EPS rendition, but prognostics going back some ten days began to suggest that the annular mode may flip back then.  I suggested that it might alleviate the melt rate ... slowing it down some.  Heh, it may just rescue 2019 from tapping 2012 on the shoulder. 

[bluewave]

1 hour ago, Typhoon Tip said:

Fwiw -the GEF -based NAM numbers have been elevating and in fact, are positive in the initialization as of last night.  They are forecasting a brief dip back to neutral or perhaps modestly negative SD, before an even more robustly positive modality out toward week two. 

This observation of reversing pressure patterns is probably related to that - 

I haven't see then EPS rendition, but prognostics going back some ten days began to suggest that the annular mode may flip back then.  I suggested that it might alleviate the melt rate ... slowing it down some.  Heh, it may just rescue 2019 from tapping 2012 on the shoulder. 

Yeah, these wild swings in the NAM have increased in amplitude as the climate has warmed. While the long term sea ice trend is down, it will probably be an up and down bumpy ride along the way.That’s why calling the exact  date for the eventual ice free state will continue to be tricky. Maybe the best we can do is just say some time between 2030 and 2050.

https://www.eurekalert.org/pub_releases/2009-01/whoi-sls011309.php

PUBLIC RELEASE: 13-JAN-2009

Study links swings in North Atlantic oscillation variability to climate warming

 

WOODS HOLE OCEANOGRAPHIC INSTITUTION

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Using a 218-year-long temperature record from a Bermuda brain coral, researchers at the Woods Hole Oceanographic Institution (WHOI) have created the first marine-based reconstruction showing the long-term behavior of one of the most important drivers of climate fluctuations in the North Atlantic.

The North Atlantic Oscillation (NAO) is a wide-ranging pressure seesaw that drives winter climate over much of North America, Europe and North Africa. Past reconstructions of the NAO have relied mainly on terrestrial, or land-based records, such as tree ring chronologies combined with ice cores and historical climate data. Those records do not fully capture oceanic processes linked to NAO variability, and short instrumental records from relatively few locations limit the understanding of ocean-atmosphere dynamics with regard to NAO behavior.

"By analyzing the coral, we were able to look at changes in the ocean relative to changes on land," said Nathalie Goodkin, lead author of the study published in the December issue of the journal Nature Geoscience. "Because they are slow growing and have long life-spans, corals can provide high resolution records that are well dated and centuries long."

As they grow, corals accrete seasonal and annual growth layers, similar to tree rings. The proportions of trace elements versus the major element (calcium) found in the layers of the skeleton largely depend on the temperature of the seawater in which it was formed. By analyzing the strontium to calcium ratio in the Bermuda brain coral, Goodkin and colleagues -- WHOI scientists Konrad Hughen, Scott Doney and William Curry -- were able to reconstruct monthly changes in ocean temperatures and evaluate variability of the NAO during both cold and warm periods from the Little Ice Age (1800�) to modern day. 

The research team found the variability of the NAO decade-to-decade (multi-decadal scale) has been larger, swinging more wildly, during the late twentieth century than in the early 1800s, suggesting that variability is linked to the mean temperature of the Northern Hemisphere. This confirms variability previously reported in past terrestrial reconstructions. 

"When the Industrial Revolution begins and atmospheric temperature becomes warmer, the NAO takes on a much stronger pattern in longer-term behavior," said Goodkin. "That was suspected before in the instrumental records, but this is the first time it has been documented in records from both the ocean and the atmosphere." 

The North Atlantic Oscillation is described by the NAO index, calculated as a weighted difference between the polar low and the subtropical high during the winter season. In a positive phase, both the low-pressure zone over Iceland and high pressure over the Azores are intensified, resulting in changes in the strength, incidence, and pathway of winter storms crossing the Atlantic. In a negative phase, a weak subtropical high and a weak Icelandic low results in fewer and weaker winter storms crossing on a more west-east pathway. 

The NAO index varies from year to year, but also exhibits a tendency to remain in one phase for intervals lasting more than a decade. An unusually long period of positive phase between 1970-2000 led to the suggestion that global warming was affecting the behavior of the NAO. 

"Anthropogenic (human-related) warming does not appear to be altering whether the NAO is in a positive or negative phase at multi-decadal time scales," said WHOI paleoclimatologist Konrad Hughen. "It does seem to be increasing variability. Clearly, this has implications for the future."

"As temperatures get warmer, there's potential for more violent swings of the NAO -- the phases becoming even more positive and even more negative," Hughen added. "If the NAO locks more into these patterns, intense storms will become more intense and droughts will become more severe." 

The climatic influence of the NAO extends from the eastern United States to Western Europe, impacting human activities such as shipping, oil drilling, fisheries, hydroelectric power generation and coastal management. Improving the ability to predict shifts in the phase and intensity of the NAO is a prerequisite to mitigating the economic impacts of future climate change.

While additional modeling and palaeoclimatic studies are needed, a broad distribution of marine records could advance our knowledge of NAO variability and serve to improve future projections, said Goodkin, now an assistant professor in the Department of Earth Sciences at the University of Hong Kong. 

 

###

 

A WHOI Ocean and Climate Change Institute Fellowship, and grants from the National Science Foundation and Woods Hole Oceanographic Institution supported this work. 

The Woods Hole Oceanographic Institution is a private, independent organization in Falmouth, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the oceans' role in the changing global environment.

Related links:

Nature GeoScience: Increased multidecadal variability of the North Atlantic Oscillation since 1781 http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo352.html

 

[ORH_wxman]

6 hours ago, Weatherdude88 said:

For 8.28, the NSIDC northern hemisphere sea ice area value is 2,945,583 square kilometers (pole hole adjustment). This is an increase of 8,066 square kilometers. 

2019 NSIDC sea ice area is in third place for the date. Area increased, however there was a minor reduction in extent, most likely due to compaction on the Atlantic front. 

 

That's the 5-day mean, the daily area actually increased 20k to 2.999 million sq km. Not that the area matters much anymore for ranking purposes...this season will rank 3rd lowest for area behind 2012 and 2016.

[ORH_wxman]

11 minutes ago, Weatherdude88 said:

For 8.29, the NSIDC northern hemisphere sea ice area 5 day trailing mean value is 2,966,727 square kilometers (pole hole adjustment). This is an increase of 21,145 square kilometers. 

Momentum has now been established in the direction of the freezing season. 

The daily area did start falling again....but it was only 18k. Down to 2.981 million sq km....the min so far was 2.877 on August 24th.

[lookingnorth]

It looks like with the possible exception of 1980, we just had the smallest Aug 13-29 sea ice extent drop on record.

[superjames1992]

Pretty crazy turnaround considering how bad things looked a few weeks back.  I mean, historically the minimum is still going to be low, but we're not going to even come close to 2012 and it looks like it's not going to be too far out of the ordinary for our "new normal" in the arctic.

[bluewave]

22 hours ago, superjames1992 said:

Pretty crazy turnaround considering how bad things looked a few weeks back.  I mean, historically the minimum is still going to be low, but we're not going to even come close to 2012 and it looks like it's not going to be too far out of the ordinary for our "new normal" in the arctic.

The dipole reversal around August 20th was one for the record books. We are not that far from the 2007-2018 NSIDC annual average daily minimum extent of 4.51 million sq km.The average minimum extent before 2007 was 6.18 million sq km from 1994 to 2005. Arctic amplification really took off once minimums began to regularly fall below 6 million sq km.

 

[Typhoon Tip]

5 hours ago, superjames1992 said:

Pretty crazy turnaround considering how bad things looked a few weeks back.  I mean, historically the minimum is still going to be low, but we're not going to even come close to 2012 and it looks like it's not going to be too far out of the ordinary for our "new normal" in the arctic.

You may just be in hyperbole there but we are definitely close to any rank inside of top 10

[superjames1992]

1 hour ago, Typhoon Tip said:

You may just be in hyperbole there but we are definitely close to any rank inside of top 10

Yes, but it was basically a guarantee that any year is going to be a top 5-10 melt season given the long-term trend.  That’s what I mean by “new normal”.

[bluewave]

2019 moves into 7th place on NSIDC extent at 4.589 million sq km as the extreme reverse dipole relaxes. Just a bit above the 2007-2018 average daily minimum extent of 4.510.

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.344....2011-9-11

4.433....2015-9-9

4.586....2018-9-23

4.589....2019

4.615....2010-9-21

4.656....2018-9-23

4.665....2017-9-13

[AfewUniversesBelowNormal]

This might be a record +AO here for a while. It's probably not as cold at the surface. 

http://mp1.met.psu.edu/~fxg1/ENSHGTAVGNH_12z/ensloopmref.html

[donsutherland1]

On August 31, Arctic sea ice extent was 4,259,262 square kilometers on JAXA.

Based on sensitivity analysis, the following are implied probabilities for various minimum extent figures:

4.25 million square kilometers or below: 99%
4.00 million square kilometers or below: 59%
3.75 million square kilometers or below: 0.6%

75th percentile: 4.041 million square kilometers
25th percentile: 3.916 million square kilometers

Minimum extent figures based on historic 2010-2018 data:

Mean decline: 3.979 million square kilometers
Median decline: 4.016 million square kilometers
Minimum decline: 4.078 million square kilometers
Maximum decline: 3.757 million square kilometers

Summary:

After a pause likely due to storminess over the Polar region, Arctic sea ice extent has again begun to decline. Arctic sea ice extent will likely decline with some momentary increases over the next 1-2 weeks. A minimum extent figure below 4.000 million square kilometers still remains possible, but the probability of that outcome has declined markedly over the past week.

[bluewave]

73k daily drop on NSIDC extent as we move past the stall period with the extreme reverse dipole pattern. This puts 2019 into 6th place.

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.344....2011-9-11

4.433....2015-9-9

4.516....2019

4.586....2018-9-23

4.615....2010-9-21

4.656....2018-9-23

4.665....2017-9-13

[forkyfork]

2 hours ago, bluewave said:

73k daily drop on NSIDC extent as we move past the stall period with the extreme reverse dipole pattern. This puts 2019 into 6th place.

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.344....2011-9-11

4.433....2015-9-9

4.516....2019

4.586....2018-9-23

4.615....2010-9-21

4.656....2018-9-23

4.665....2017-9-13

it's now a regular dipole. we could see big late losses for the next week or so

[bluewave]

20 hours ago, forkyfork said:

it's now a regular dipole. we could see big late losses for the next week or so

Larger 97k drop yesterday puts 2019 into 5th place for lowest annual daily NSIDC extent.

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.344....2011-9-11

4.419....2019

4.433....2015-9-9

4.586....2018-9-23

4.615....2010-9-21

4.656....2018-9-23

4.665....2017-9-13

[SnoSki14]

On 8/30/2019 at 9:42 AM, Weatherdude88 said:

For 8.29, the NSIDC northern hemisphere sea ice area 5 day trailing mean value is 2,966,727 square kilometers (pole hole adjustment). This is an increase of 21,145 square kilometers. 

Momentum has now been established in the direction of the freezing season. 

Wrong again

[donsutherland1]

On 8/25/2019 at 9:52 AM, Weatherdude88 said:

For 8.24, the NSIDC northern hemisphere sea ice extent value is 4.668 millions of square kilometers. This is an increase of 17,000 square kilometers.

2019 now has 662,000 square kilometers more sea ice extent than 2012. 2019 now has 210,000 square kilometers less sea ice than 2016, and 169,000 square kilometers less than 2007 for the date.

We have our first candidate for the 2019 northern hemisphere sea ice minimum (historically unprecedented and unlikely for minimum this early). We have seen two consecutive days of gains in the data set. We are now 40,000 squared kilometers above the August 22^nd value.

The Slater Probabilistic Sea Ice Extent forecast has been predicting a late August minimum.

Due to the latitudinal and longitudinal position of the sea ice, I would not be surprised if we see a record early minimum this year (In the next week). Most of the easy sea ice has already melted. The majority of the remaining sea ice is at high latitudes.

Additionally, we may be entering a sustained period of below average temperatures in the areas where we have some vulnerable sea ice. In these same areas, most of the summer featured anomalously warm temperatures.

 Regardless, there is a possibility we fall behind 2016 in the next 3-6 days and 2007 in the next 6-9 days.

 

 

 

 

 

 

 

As you noted correctly, had there been an August minimum, it would have been unprecedented. Since 8/31, Arctic sea ice extent has continued to decline. That a piece of guidance would suggest an unprecedented situation, moreso when the upper air pattern had been forecast to grow more favorable for continued reductions in sea ice, raises some questions about the model itself. I'm not sure what the track record of the model in question is, but this is a high profile miss. Overall, forecasting of sea ice minimums remains a fairly low skill endeavor at present.

[Typhoon Tip]

On 9/3/2019 at 8:09 AM, donsutherland1 said:

As you noted correctly, had there been an August minimum, it would have been unprecedented. Since 8/31, Arctic sea ice extent has continued to decline. That a piece of guidance would suggest an unprecedented situation, moreso when the upper air pattern had been forecast to grow more favorable for continued reductions in sea ice, raises some questions about the model itself. I'm not sure what the track record of the model in question is, but this is a high profile miss. Overall, forecasting of sea ice minimums remains a fairly low skill endeavor at present.

I haven't been a part of this conversation stream recently so pardon if this is more at obtrusive ... It might  ( or not   ) be worth noting that the GEFs have been elevating the mode of the NAM since ~ mid August.  In a vacuum, that putts the "had been forecast" part of this bold statement in question for me. 

As we know,  a positive 'Annular Mode reverses the temperature anomaly correlations and would result/conducive to better ice retention. 

This is purely linear-statistical discussion point, however, and does not consider the bevy of other environmental factors that "synergistically" can also effect melt rates ...such as salinity variance and momentum, dark sea vs albedo surface absorption of solar...etc etc etc...  Nonetheless, some of the graphical slowing in recent 10 days does actually fit that GEFs modality of the NAM in at least conceptual acceptance -  

[donsutherland1]

1 hour ago, Typhoon Tip said:

I haven't been a part of this conversation stream recently so pardon if this is more at obtrusive ... It might  ( or not   ) be worth noting that the GEFs have been elevating the mode of the NAM since ~ mid August.  In a vacuum, that putts the "had been forecast" part of this bold statement in question for me. 

As we know,  a positive 'Annular Mode reverses the temperature anomaly correlations and would result/conducive to better ice retention. 

This is purely linear, however, and does not consider the bevy of other environmental factors that "synergistically" can also effect melt rates ...such as salinity variance and momentum, dark sea vs albedo surface absorption of solar...etc etc etc...  But, some of the graphical slowing in recent 10 days does actually fit that GEFs modality of the NAM in at least conceptual acceptance -  

Let me rephrase things a little. The pattern was not forecast to be especially unfavorable to ice reduction. The forecast showed fluctuations in the NAM, not a persistent anomaly. One would have needed a fairly extraordinary development to lead to an unprecedented early end to melt season. The MAN had been forecast to slide back toward neutral during the first week of September. All other things being equal, that suggested reductions in Arctic sea ice would continue probably for another week and perhaps two.

[Typhoon Tip]

22 minutes ago, donsutherland1 said:

Let me rephrase things a little. The pattern was not forecast to be especially unfavorable to ice reduction. The forecast showed fluctuations in the NAM, not a persistent anomaly. One would have needed a fairly extraordinary development to lead to an unprecedented early end to melt season. The MAN had been forecast to slide back toward neutral during the first week of September. All other things being equal, that suggested reductions in Arctic sea ice would continue probably for another week and perhaps two.

Well ...yeah, and in that same spirit of "semantic fairness" ... the rise in the NAM hasn't been exactly overwhelmingly coherent... The lay-folk web-access site over CPC has it more like languidly elevating beginning two weeks ago ... finally succeeding at some point over the next 10 days. 

So, yeah.  It's not a hugely convincing modality as you/we can see.  Nevertheless...some slowing in melt rates is plausibly related. 

The thing is, the Arctic is sensitive to phase changes because of physics to put it bluntly. The thermal tolerance for ice->water->ice is narrow.   Such that subtle variations in thermal contribution may have a seemingly larger proportionate response than one might think or be aware, if we're talking about some hypothetical formula of ( sun + dark vs ice covered albedo ocean surface + salinity variance + 1°C )  ... alter any one of these variables and the system presence a change, but if more than one of them gets altered that significance hockey-sticks in a real hurry... and so on... 

However the real equation of environmental factors that determines ice retention in the summer really works... we do know that the system is sensi ... So I find it intriguing that the GEFs begin signaling a relaxed negative Annular mode and then a week to two weeks later ...monitoring showed slowing...  That doesn't seem like coincidence?  But you and I are not parked out on the ice cap in a research hut either. 

[bluewave]

One of the largest NSIDC daily extent losses for the month of September on the 4th. The 112 k daily drop moves 2019 into 4th place. The late August stall followed by accelerated losses is a first for the post 2007 Arctic. It shows how volatile the Arctic pressure patterns have become.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.286.....2019

4.344....2011-9-11

4.433....2015-9-9

4.586....2008-9-19

4.615....2010-9-21

4.656....2018-9-23

4.665....2017-9-13

[lookingnorth]

7 hours ago, bluewave said:

One of the largest NSIDC daily extent losses for the month of September on the 4th. The 112 k daily drop moves 2019 into 4th place. The late August stall followed by accelerated losses is a first for the post 2007 Arctic. It shows how volatile the Arctic pressure patterns have become.

ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/seaice_analysis/Sea_Ice_Index_Daily_Extent_G02135_v3.0.xlsx

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.286.....2019

4.344....2011-9-11

4.433....2015-9-9

4.586....2018-9-23

4.615....2010-9-21

 4.656....2018-9-23

4.665....2017-9-13

Why is 2018 in there twice?

[bluewave]

36 minutes ago, lookingnorth said:

Why is 2018 in there twice?

Typo. 7th place should read 2008.

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.286.....2019

4.344....2011-9-11

4.433....2015-9-9

4.586....2008-9-19

4.615....2010-9-21

 4.656....2018-9-23

 4.665....2017-9-13

[aperson]

On 8/30/2019 at 2:12 PM, bluewave said:

The dipole reversal around August 20th was one for the record books. We are not that far from the 2007-2018 NSIDC annual average daily minimum extent of 4.51 million sq km.The average minimum extent before 2007 was 6.18 million sq km from 1994 to 2005. Arctic amplification really took off once minimums began to regularly fall below 6 million sq km.

 

 

Don't look now or you may get whiplash. Energy from Lingling and Dorian in tandem with the current configuration look to constructively split the TPV and resume a +DA pattern.

 

[bluewave]

NSIDC daily extent down another 48k to 4.238 million sq km. This was the largest drop from 8-29 to 9-4 going back to 2007.

8-29 to 9-4 Arctic sea ice decline 

2019...-409k

2018...-130k

2017...-119k

2016...-248k

2015...-98k

2014...-174k

2013...-161k

2012...-146k

2011....-291k

2010....-266k

2009....-159k

2008.....-326k

2007.....-272k

[Typhoon Tip]

Fwiw ... and I'm sure others are aware of this - or should be... The mean nadir going back a decade doesn't typically occur until the 15th thru the 20th ... There are a few years as others have noted where the minimum is achieved at an earlier date.   

Anyway, I suspect that the momentum and back-ground do not really favor the earlier nadir scenario.  Whether that results in historic lows, notwithstanding.  I suspect whether we do see that or not, we're losing ice until the Equinox.  

It'll be interesting to see - 

[bluewave]

Odd late season behavior continues on NSIDC extent. Extent has increased 95k last 2 days. It was 4.238 million sq km on 9-4 and now 4.333 million sq km for the 6th.  The melt season featured a record low extent for July only to fall back to 4th place as of 9-6. Big slowdown after mid August followed by an acceleration of losses into early September. 

Currently in 4th place for NSIDC extent. 

3.387....2012-9-17

4.155....2007-9-18

4.165....2016-9-10

4.333....2019

4.344....2011-9-11

 4.433....2015-9-9

4.586....2008-9-19

 4.615....2010-9-21

 4.656....2018-9-23

 4.665....2017-9-13

Zack Labe notes the statistical tie for record Arctic warmth this summer with 2012.

https://mobile.twitter.com/ZLabe/status/1170022132216029185

Boreal summer 2-m temperatures were statistically tied (with 2012) for the warmest on record in the #Arctic [using JRA-55 data]

 

 

 

 

 

 

[bluewave]

33 minutes ago, Weatherdude88 said:

 

There is nothing "odd" about NSIDC sea ice extent, and sea ice does not exhibit "behavior".

If you remove 9.4 from the daily NSIDC area data set, 8.24 would have the lowest daily area value for the current melting season. The weather dispersed and then compacted sea ice these last two weeks. The freezing momentum was enough to get us within one day of having a record early sea ice area minimum. The current distribution and orientation of sea ice will not allow for much more compaction.

There is now more freezing than melting in the arctic. This is consistent with the significant 59,524 square kilometer increase in area, looking at the daily value for 9.5. The freezing season is here.

The term behavior is commonly used when referring to sea ice. Odd would be a mild term for describing the first time pressure extremes that this season has exhibited. Those extremes lead to the unusual pattern of sea ice loss this melt season.